WO2007078020A1

WO2007078020A1 - Exhaustion system for fuel evaporation gas of vehicles

Info

Publication number: WO2007078020A1
Application number: PCT/KR2006/000034
Authority: WO
Inventors: Jong-Dae Lim
Original assignee: Inzi Controls Co., Ltd.
Priority date: 2006-01-03
Filing date: 2006-01-04
Publication date: 2007-07-12
Also published as: KR100695930B1

Abstract

A fuel evaporative emission exhaust system for a vehicle, which exhausts fuel evaporative emissions from a fuel tank by supplying the fuel evaporative emissions to an intake manifold (22) of an engine room via a catalytic converter (1). The fuel evaporative emission exhaust system includes an emission supply 'tube (50) connected between the catalytic converter and the intake manifold to supply the fuel evaporative emissions to the intake manifold, an on/off valve (70) installed on the emissions supply tube to periodically open and close a path of the emission supply tube for a predetermined time, and a separator (80) for temporarily dividing a path of the emission supply tube into separated paths to temporarily divide a flow of the fuel evaporative emission into separated flows.

Description

[DESCRIPTION]

[invention Title]

EXHAUSTION SYSTEM FOR FUEL EVAPORATION GAS OF VEHICLES [Technical Field]

The present invention relates to a fuel evaporative emission exhaust system for a vehicle, and more particularly, to an exhaust system that can exhaust the fuel evaporative emissions, which is formed as a result of the fuel evaporation in a fuel tank, through an intake manifold disposed in an engine room by directing the fuel evaporative emissions passing through a catalytic converter of the vehicle to the intake manifold. [Background Art]

Generally, evaporative emissions are generated due to the fuel evaporation in a fuel tank of a vehicle. Evaporative emissions can be a much greater source of HC (Hydrocarbon) air pollution. Approximately 15% of all HC emissions from the vehicle originate from evaporative emissions. Therefore, in order to prevent the evaporative emissions from escaping to the atmosphere, an evaporative emission exhaust system for purifying the evaporative emissions is provided to the vehicle.

FIG. 1 shows a conventional evaporative emission exhaust system. Referring to FIG. 1, the evaporative emissions in a fuel tank T passes through a catalytic converter 12 filled with carbon and is then directed to the intake manifold 22 that is in a vacuum state through an emission supply tube 2. Therefore, the evaporative emissions is purified in the catalytic converter and then exhausted through the intake manifold. At this point, the evaporative emissions are supplied from the emission supply tube 2 to the intake manifold 22 at an ultrahigh flow rate by the vacuum pressure of the intake manifold 22.

A solenoid type on/off value 16 installed on the emission supply tube 2 periodically opens and closes the emission supply tube 2 at a valve stroke of 10-30 times per second. Therefore, the evaporative emissions are supplied to the intake manifold 22 at an ultrahigh flow rate only when the solenoid type on/off value 16 is opened.

Since the solenoid type on/off value 16 periodically opens and closes the emission supply tube 2 for a preset time, the evaporative emission is not continuously supplied to the intake manifold but intermittently supplied many times per second according to the valve stroke. That is, the evaporative emissions flowing along the tube 2 at the ultrahigh flow rate are intermittently supplied to the intake manifold according to the valve stroke numbers per second. Since the evaporative emissions are intermittently supplied by the solenoid type on/off value according to the valve stroke numbers per second, as shown in FIG. 2, a pulsating wave motion is generated by the evaporative emissions. The wave motion is generated by 10-30 times per second by the solenoid type on/off value 16. That is, the pulsating wave motion is generated as the solenoid type on/off value 16 repeatedly and quickly opens and closes a passage of the emission supply tube 2. Therefore, the pulsating wave motion is amplified while being transferred along the emission supply tube 2. That is, the pulsating wave motion is generated and amplified by the repeated open and close operation of the solenoid type on/off value 16. As a result, a tremendous noise is generated by the pulsating wave motion while the evaporative emission surges along the emission supply tube 2. At this point, a chamber unit 14 installed on the emission supply tube 2 provides an enlarged spaced for the evaporative emissions flowing toward the intake manifold 22 to buffer the evaporative emission flowing at an ultrahigh flow rate. Therefore, the pressure of the evaporative emissions flowing from the emission supply tube 2 to the intake manifold 22 is reduced by the chamber unit 14 and supplied to the intake manifold 22. The energy (i.e., an amplitude) of the pulsating wave motion is reduced as the pressure of the evaporative emission is reduced. As the amplitude of the pulsating wave motion of the emission supply tube 2 is reduced, the vibration of the emission supply tube as well as the noise are somewhat reduced.

As described above, the conventional exhaust system essentially requires the chamber unit 14 in order to reduce the noise and vibration of the emission supply tube 2. Therefore, the manufacturing costs of the vehicle increase. In addition, due to the volume of the chamber unit 14, the engine room space (or the space between a chassis and an interior room of the vehicle) is reduced. Furthermore, since the chamber unit 14 cannot sufficiently reduce the pressure of the fuel evaporative emission, the noise and vibration caused by the pulsating wave motion are not yet sufficiently reduced.

Meanwhile, the reference numbers 3 and 18 denotes respectively an air supply tube connected to the catalytic converter 1 and a pressure regulator valve for regulating the pressure of the catalytic converter 1 by supplying the atmospheric pressure through the air supply tube 1. The reference number 24 indicates an electronic control unit (ECU) for controlling the operation of the solenoid type on/off value and the reference sign P denotes a pump for pumping out the fuel.

[Disclosure] [Technical Problem] The present invention is made in an effor to solve the above-described probems of the prior art and it is an object of the present invention to provide a fuel evaporative emission exhaust system for a vehicle that can reduce pressure of the fuel evaporative emission as well as the amplitude of a pulsating wave by temporarily dividing the flow of the fuel evaporative emissions in an emission supply tube and connecting the divide flow of the fuel evaporative emissions together. [Technical Solution] The above objects can be achieved by a fuel evaporative emission exhaust system for a vehicle, which exhausts fuel evaporative emissions from a fuel tank by supplying the fuel evaporative emissions to an intake manifold of an engine room via a catalytic converter, the fuel evaporative emission exhaust system including: an emission supply tube connected between the catalytic converter and the intake manifold to supply the fuel evaporative emissions to the intake manifold; an on/off valve installed on the emissions supply tube to periodically open and close a path of the emission supply tube for a predetermined time; and a separator for temporarily dividing a path of the emission supply tube into separated paths to temporarily divide a flow of the fuel evaporative emission into separated flows. The separator may be installed in the emission supply tube. Preferably, the separator may be installed in the emission supply tube near the intake manifold. More preferably, the separator may be installed in the emission supply tube near the on/off valve. Alternatively, the separator may be installed in the emission supply tube between the catalytic converter and the emission supply tube. At this point, the emission supply tube may be integrally formed with the on/off valve through welding or forming such that it can communicate with the on/off valve. Therefore, the separator may be placed inside the on/off valve. That is, the separator may be built in the on/off valve.

The separator includes a plurality of tubes 82 that are installed in a portion df the emission supply tube along an axis of the emission supply tube and integrally arranged in parallel to each other to temporarily divide the flow of the fuel evaporation emissions flowing along the emission supply tube 50 into the separated flows. The integration of the tube may be realized during a forming process. Alternatively, the tubes may be separately prepared and jointed together in parallel with each other by adhesive or other fasteners such as a clamp or a coupling member. The tubes provide a frictional resistance to the fuel evaporative emissions flowing along the path of the emission supply tube to reduce the pressure of the fuel evaporative emissions.

The tubes have different lengths from each other such that a step difference is formed between the tubes 82 so that the separated flows can be joined again at a predetermined time interval. At this point, the step difference may be formed at upstream and/or downstream ends of the tubs. When the tubes have different lengths from each other such that the step difference is formed, the incoming and outgoing time of the fuel evaporative emissions into and out of the tubes are different. The fuel evaporative emissions whose flow is divided into separated flows by the tubes receive different frictional resistances due to the different length between the tubes, the outgoing times of the fuel evaporative emissions out of the tubes differ from each other. Therefore, the separated flows are joined together at a predetermined time interval after when come out of the tubes.

The tubes may be provided with at least one through hole functioning as an emission exhaust hole through which the fuel evaporative emissions passing through the tube are exhausted. Therefore, the fuel evaporative emissions passing through the tubes are dispersed through the emission exhaust hole. Thus, the evaporative emissions passing through the tubes are mixed with each other with an increased time interval. That is, the exhausting time of the fuel evaporative emissions passing through the tubes are completely different from the exhausting time of the fuel evaporative emissions fully passing through the path of the emission supply tube and thus the evaporative emissions passing through the tubes are mixed with each other with an increased time interval. Alternatively, the separator may include a barrier assembly installed in a portion of the emission supply tube along an axis of the emission supply tube to provide a separation wall in the emission supply tube. The barrier assembly provides a frictional resistance to the fuel evaporative emissions flowing along the emission supply tube. The barrier assembly may include a vertical plate vertically installed in the emission supply tube to separate the internal portion of the emission supply tube into left and right halves. Alternatively, the barrier assembly may includes a horizontal plated horizontally installed in the emission supply tube to separate the internal portion of the emission supply tube into upper and lower halves. The barrier assembly may include a plurality of plates installed in the emission supply tube at predetermined intervals.

According to a preferred embodiment of the present invention, the barrier assembly includes a horizontal plate horizontally installed in the emission supply tube 50 to horizontally divide the internal portion of the emission supply tube and a vertical plate vertically disposed on the horizontal plate to vertically divide the internal portion of the emission supply tube. The vertical and horizontal plates may be integrally formed with each other through a forming process. The vertical plate may vertically extend along a central axis of the horizontal plates. The vertical plate may be formed on one of top and bottom portions of the horizontal plate. When the vertical plate is formed on one of the top and bottom portions, the barrier assembly has a 4- or T-shaped cross section. Therefore, the barrier assembly divides the internal section of the emission supply tube into three sections. Alternatively, the vertical plate may be formed on top and bottom portions of the horizontal plate. In this case, the barrier assembly has a +-shaped section and thus the internal section of the emission supply tube is divided into four sections. The horizontal and vertical plates may be provided by plurality. In this case, the internal section is divided into many sections .

Preferably, the vertical play may be formed on the top and bottom portions of the horizontal plate and the vertical plate formed on the top portion differs in a length from the vertical plate formed on the bottom portion such that a step difference is formed between the first and second vertical portions and thus the separated flows can be joined again at a predetermined time interval. At this point, the step difference may be formed at upstream and/or downstream ends of the vertical plate. When, the top and bottom portions of the vertical plate have different lengths from each other such that the step difference is formed, the incoming and outgoing time of the fuel evaporative emissions into and out of the barrier assembly are different. Therefore, the separated flows are joined together at a predetermined time interval after when come out' of the barrier assembly.

A ratio of a length of the step difference between the tubes or between the top and bottom portions of the vertical plate to a length of the tube or the horizontal plate is preferably about 12-45:100. That is, when the length of the tube or the horizontal plate is 100, the length of the step difference is 12-45. When the length of the step difference is too long, the contact area between the tubes or between the vertical and horizontal plates is reduced in proportional to the length of the step difference. When the contact area is reduced, the coupling force between the tubes or between the horizontal and vertical plates is reduced. Therefore, the length of the step difference is limited to the above ratio to prevent the coupling force is reduced.

Meanwhile, the tubes and barrier assembly may be formed of metal, rubber or poly-based synthetic reins such as polyurethane, POM-PoIy Oxy Methylene-, and the like. Preferably, the tubes and barrier assembly are formed of the rubber or synthetic resin considering the manufacturing and installing processes. In this case, the tubes or the vertical and horizontal plates are integrally formed in a single body. Therefore, the tubes and barrier assembly have each self- elastic force so that it can be easily fitted in the emission supply tube by the interference fit. [Advantageous Effects]

According to the fuel evaporation emission exhaust system for a vehicle of the present invention, since the separator temporarily divides the flow of the fuel evaporative emissions, which is directed to the intake manifold at an ultrahigh flow rate, into the separated flows and allow the separated flows to be joined together at a predetermined time interval, the amplitude of the pulsating wave motion can be reduced and thus the noise generated from the fuel evaporative emission exhaust system can be reduced. Furthermore, the vibration of the emission supply tube caused by the fuel evaporative emission flowing along the emission supply tube can be prevented.

Particularly, since the noise of the fuel evaporative emission exhaust system can be reduced and the vibration of the emission supply tube by the wave motion of the fuel evaporative emissions can be prevented, the chamber unit that has been used in the conventional art can be omitted. [Description of Drawings] FIG. 1 is a schematic view of a conventional fuel evaporative emission exhaust system for a vehicle; FIG. 2 is a graph illustrating a pulsating wave motion of the conventional fuel evaporative emission exhaust system; FIG. 3 is a side view of a fuel evaporative emission exhaust system for a vehicle according to an embodiment of the present invention; FIG. 4 is a perspective view of a state where the separator of FIG. 3 is supplying fuel evaporative emissions; FIG. 5 is a graph illustrating a pulsating wave motion of the fuel evaporative emission exhaust system of FIG. 3; FIG. 6 is a modified example of the separator of FIG. 3; and

FIG. 7 is a perspective view of a state where the separator of FIG. 6 is supplying fuel evaporative emissions; [Best Mode]

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to accompanying drawings. FIG. 3 is a side view of a fuel evaporative emission exhaust system for a vehicle according to an embodiment of the present invention, FIG. 4 is a perspective view of a state where the separator of FIG. 3 is supplying fuel evaporative emissions, and FIG. 5 is a graph illustrating a pulsating wave motion of the fuel evaporative emission exhaust system of FIG. 3.

Referring first to FIG. 3, a fuel evaporative emission exhaust system for a vehicle according to this embodiment includes a catalytic converter 1 and an intake manifold 22 that are interconnected by an emission supply tube 50. That is, the fuel evaporative emissions is directed from the catalytic converter 1 to the intake manifold 22, which is in a vacuum state, along the emission supply tube 50. That is, the fuel evaporative emissions exhausted from the catalytic converter 1 are supplied to the intake manifold 22 along the emission supply tube 50 at an ultrahigh flow rate by vacuum pressure of the intake manifold 22.

A solenoid type on/off value 70 is installed on the emission supply tube 50. The solenoid type on/off value 70 is interposed between the catalytic converter 1 and the intake manifold 22. That is, the solenoid type on/off value 70 is integrally formed with a portion of the emission supply tube 50 while communicating therewith. At this point, the solenoid type on/off value 70 is placed close to the intake manifold 22.

That is, the emission supply tube 50 is divided into separated sections that are interconnected by the solenoid type on/off value 70. The solenoid type on/off value 70 periodically opens and closes a passage of the emission supply tube 50 at a valve stroke of 10-30 times per second so as to prevent the emission supply tube 50 from being vacuumed by the intake manifold 22. That is, the solenoid type on/off value 70 opens and closes the passage of the emission supply tube 50 10-30 times per second. Therefore, the evaporative emissions are intermittently supplied to the intake manifold 22 by the solenoid type on/off value 70 many times per second.

Meanwhile, a separator 80 is installed in the emission supply tube 50 as shown in a left enlarged view of FIG. 3. The separator 80 includes two tubes interconnected in parallel to each other. The^' tubes 82 are formed of elastic synthetic resin so that they can be forcedly fitted in the emission supply tube 50. The two tubes 82 may be integrally formed with each other through a molding process. As shown in a right enlarged view of FIG. 3, the tubes 82 is arranged along an axis of the gas. Therefore, the flow of the evaporative emissions along the emission supply tube 50 is temporarily divided into separated flows and the separated flows are joined together at a predetermined time interval.

The tubes 82 are arranged in parallel to each other as shown in FIG. 3 and different in a length from each other. At this point, downstream ends of the tubes 82 is identically located such that there is a step different ΔL between upstream ends of the tubes 82 due to the length difference between the tubes 82.

Referring to FIG. 4, the tubes 82 allow the fuel evaporative emissions to be divided into different flows and exhausted. Therefore, the flow of the fuel evaporative emissions is temporarily divided into separated flows by the tubes 82 and the separated flows are joined together again.

The operation of the above-described fuel evaporative emission exhaust system for the vehicle will now be described with reference to FIGS. 3 through 5. Referring to FIG. 3, the fuel evaporative emissions exhausted from the catalytic converter 1 is directed toward the intake manifold 22 by the vacuum pressure of the intake manifold 22. Therefore, the gas supply tube 50 supplies the fuel evaporative emissions to the intake manifold 22.

At this point, the solenoid type on/off value 70 mounted communicating with the emission supply tube 50 periodically opens and closes the passage of the emission supply tube 50 for a predetermined time to control the flow of the fuel evaporative emissions to the intake manifold 22. The vacuum pressure is separated many times by the solenoid type on/off value 70 and supplied to the emission supply tube 50. Therefore, the fuel evaporative emissions 50 are supplied to the intake manifold 22 along the emission supply tube 50 while being separated many times. Therefore, a pulsating wave motion is generated in the emission supply tube 50 due to the fuel evaporative emissions that are quickly divided many times. That is, the pulsating wave motion is generated in the emission supply tube 50 by the repeated, quick opening/closing operation of the solenoid type on/off value 70. Referring to FIG. 4, the tubes 82 of the separator 80 temporarily divides the flow of the fuel evaporative emissions, which are exhausted from the chamber unit 60 at the ultrahigh flow rate, into separated flows. That is, the flow of the fuel evaporative emissions is divided into two flows as they go into the ,tubes 82 and the two flows are joined together as they come out of the tubes 82. The joined flow of the evaporative emissions is directed to the solenoid type on/off value 70.

At this point, due to the step difference ΔL between upstream ends of the tubes 82, the incoming time of the fuel evaporative emissions to one tube 82 is different from that of the fuel evaporative emissions to the other tube 82. In addition, due to the difference in the length between the tubes 82, the frictional resistances between the tubes 82 are different from each other. Therefore, the outgoing time of the fuel evaporative emissions from one tube 82 is different from that of the fuel evaporative emissions from the other tube 82. Thus, the fuel evaporative emissions G are exhausted from the tubes 82 with a step difference ΔL. Therefore, the flow of the fuel evaporative emissions G are temporarily divided into two separated flows by the tubes 82 and the separated flows of the fuel evaporative emissions G are joined together at a predetermined time interval by the step different ΔL. While the fuel evaporative emissions G pass through the tubes 82, the pressures thereof are reduced by the frictional resistances of the tubes 82.

Referring to FIG. 5, the pulsating wave motion generated in the emission supply tube 50 is reduced as compared with the conventional art. In the graph of FIG. 5, the dotted-waveform denotes the conventional pulsating wave motion while the solid-waveform denotes the pulsating wave motion generated by the above-described embodiment, As shown in the graph of FIG. 5, the pulsating wave motion generated by the above-described embodiment forms two waveforms having a phase difference as the flow of the fuel evaporative emissions is divided into two separated flows by the tubes 82 and the separated flows are joined together at a predetermined time interval. That is, as the flow of the fuel evaporative emissions is divided into two separated flows by the tubes 82 and the separated flows are joined together at a predetermined time interval, the pulsating wave motion forms two waveforms having the phase difference. At this point, as the pressure of the fuel evaporation emissions is reduced by the tubes 82, the pulsating wave motion has amplitude lower than that of the conventional art. That is, the amplitude of the pulsating wave motion generated by the above-described embodiment is reduced.

The reference number 60 of FIG. 3 indicates the chamber unit. The chamber unit 60 is a hollow cavity that is formed on the emission supply tube 50 between the catalytic converter 1 and the solenoid type on/off value 70. At this point, the chamber unit 60, communicates with the emission supply tube 50.

The chamber unit 60 provides the enlarged space for the fuel evaporative emissions directed from the catalytic converter 1 to the solenoid type on/off value 70. Therefore, the fuel evaporative emissions that is supplied from the catalytic converter 1 to the intake manifold 22 at the ultrahigh flow rate by the vacuum pressure of the intake manifold 22 is buffered at the chamber unit 60. That is, the chamber unit 60 buffers the fuel evaporative emissions and supplies the same to the emission supply tube 50 directed to the intake manifold 22.

As the chamber unit buffers the fuel evaporative emissions, the fuel evaporative emissions that are reduced in its pressure by the tubes 82 are further reduced in the pressure by the chamber unit 60. Therefore, the pressure of the emission supply tube 50 is more stably converted by the chamber unit 60.

In conclusion, the chamber unit 60 compensates for the function of the separator 80. If necessary, the chamber unit 60 may be omitted. FIG. 6 is a modified example of the separator of FIG. 3 and FIG. 7 is a perspective view of a state where the separator of FIG. 6 is supplying fuel evaporative emissions. A constitution and operation^' of a separator according to this modified example will now be described. Referring to FIG. 6, a separator of this modified example is installed in the emission supply tube 50 along an axis the emission supply tube 50. The separator 80 is built in a portion of the emission supply tube 50 includes a barrier assembly 84 defining a separation wall inside the emission supply tube. At this point, the barrier assembly 84 is placed at a same location as the tubes 82 of the foregoing example. That is, the barrier assembly 84 functions as the tubes 82 of the foregoing example.

The barrier assembly 84 includes a horizontal plate 84a and upper and lower vertical plates 84b. The upper and lower vertical plates 84b are integrally formed on top and bottom surfaces of the horizontal plate 84a along a center line of the horizontal plate 84a. Therefore, the barrier assembly 84 has a +?shaped cross-section.

The barrier assembly 84 is formed of synthetic resin having a slight elastic force. The horizontal and vertical plates 84a and 84b may be formed in a single body. The barrier assembly 84 is fixed in the emission supply tube 50 by interference fit using the property of the synthetic resin. As the barrier assembly 84 is forcedly fitted in the emission supply tube 50, the internal portion of the emission supply tube 50 is divided into upper and lower halves by the horizontal plate 84a and further divided into left and right halves by the vertical plate 84b. That is, the horizontal plate 84a divides horizontally the internal portion of the emission supply tube 50 and the vertical plate 84b divides vertically the internal portion of the emission supply tube 50. Therefore, the internal portion of the gas supply tube 50 is divided into four compartments . As shown in FIG. 6, there is a step difference ΔL on the vertical plate 84b. This step different ΔL is formed by a length of the vertical plate 84b relative to a length of the horizontal plate 84a. The step different ΔL is formed on both the top and bottom surfaces of the horizontal plate 84a. That is, the vertical plates 84b ..integrally formed on the top and bottom surfaces of the horizontal plate 84a have the step different ΔL.

At this point, a length of the vertical plate 84b integrally formed on the top surface of the horizontal plate 84a differs from that of the vertical plate 84b integrally formed on the bottom surface of the horizontal plate 84a. Therefore, the vertical plates 84b have at their upstream ends the step difference ΔL.

Referring to FIG. 7, .-the barrier assembly 84 of the separator 80 divides the flow of the fuel evaporative emissions into four flows by the horizontal and vertical plates 84a and 84b. Then, the divided four flows of the fuel evaporative emissions are joined together while coming out of the barrier assembly 84.

At this point, due to the step difference ΔL between the vertical plates 84b, the incoming time of the fuel evaporative emissions to the upper compartments differs from that of the fuel evaporative emissions to the lower compartments. In addition, due to the difference in the length between the vertical plates 84b, the frictional resistances provided by the vertical plates 84b are different from each other. Therefore, the outgoing time of the fuel evaporative emissions from the upper compartments is different from that of the fuel evaporative emissions from the lower compartment. Thus, the fuel evaporative emissions G are exhausted from the barrier assembly 84 with a step difference ΔL. Therefore, the flow of the fuel evaporative emissions G are temporarily divided into two separated flows by the barrier assembly 84 and the separated flows of the fuel evaporative emissions G are joined together at a predetermined time interval by the step different ΔL. While the fuel evaporative emissions G pass through the vertical plates 84b, the pressures thereof are reduced by the frictional resistances of the vertical plates 84b.

As described above, as the separated flows are joined together at a predetermined time interval and the pressure of the fuel evaporation emissions is reduced by the vertical plates 84b, the amplitude of the pulsating wave motion generated in the emission supply tube 50 is reduced.

While the present invention has been described and illustrated herein with reference to the preferred embodiments thereof, it will be apparent to those skilled in the art that various modifications and variations can be made therein without departing from the spirit and scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention that come within the scope of the appended claims and their equivalents . [industrial Applicability]

Particularly, since the noise of the fuel evaporative emission exhaust system can be reduced and the vibration of the emission supply tube by the wave motion of the fuel evaporative emissions can be prevented, the chamber unit that has been used in the conventional art can be omitted.

Claims

[CLAIMS]

[Claim l]

A fuel evaporative emission exhaust system for a vehicle, which exhausts fuel evaporative emissions from a fuel tank by supplying the fuel evaporative emissions to an intake manifold of an engine room via a catalytic converter, the fuel evaporative emission exhaust system comprising: an emission supply tube connected between the catalytic converter and the intake manifold to supply the fuel evaporative emissions to the intake manifold; an on/off valve installed on the emissions supply tube to periodically open and close a path of the emission supply tube for a predetermined time; and a separator for temporarily dividing a path of the emission supply tube into separated paths to temporarily divide a flow of the fuel evaporative emission into separated flows .

[Claim 2] The fuel evaporative emission exhaust system of claim 1, wherein the separator includes a plurality of tubes that are installed in a portion of the emission supply tube along an axis of the emission supply tube and integrally arranged in parallel to each other to temporarily divide the flow of the fuel evaporation emissions flowing along the emission supply tube into the separated flows. [Claim 3]

The fuel evaporative emission exhaust system of claim 2, wherein the tubes have different lengths from each other such that a step difference is formed between the tubes so that the separated flows can be joined again at a predetermined time interval . [Claim 4]

The fuel evaporative emission exhaust system of claim 1, wherein the separator includes a barrier assembly installed in a portion of the emission supply tube along an axis of the emission supply tube to provide a separation wall in the emission supply tube. [Claim 5]

The fuel evaporative emission exhaust system of claim 4, wherein the barrier assembly includes: a horizontal plate horizontally installed in the emission supply tube to horizontally divide the internal portion of the emission supply tube; and a vertical plate vertically disposed on the horizontal plate to vertically divide the internal portion of the emission supply tube. [Claim β]

The fuel evaporative emission exhaust system of claim

5, wherein the vertical plate is formed on top and bottom portions of the horizontal plate and the vertical plate formed on the top portion ^■ differs in a length from the vertical plate formed on the bottom portion such that a step difference is formed between the first and second vertical portions and thus the separated flows can be joined again at a predetermined time interval.