JP2019167899A - Gas liquid separation device - Google Patents

Abstract

To provide a gas liquid separation device for separating gas-liquid two-phase flow of fuel into liquid fuel and fuel vapor.SOLUTION: A gas liquid separation device 20 comprises a base member 40 provided with plural open holes 41 and plural shaft members 51, and forms a gas-liquid separation chamber 70 by a radial clearance among the open holes 41 and the shaft members 51. The gas-liquid separation chamber 70 comprises: a first area 71 formed at a side of a housing inlet 32 to flow in gas-liquid two-phase flow; an enlarged space part 72a arranged at a downstream side of the first area 71 and having a larger flow passage sectional area than that of the first area 71 to guide fuel vapor; and a second area 72 provided with a groove-like guide part 72 arranged in side-by-side to the enlarged space part 72a, formed in at least one of an inner peripheral surface of the open holes 41 and outer peripheral surfaces of the shaft members 51 so as to guide liquid fuel to a lower part while adhering liquid fuel by surface tension.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a gas-liquid separator.

  In an automobile equipped with an engine, fuel vapor is generated in the fuel tank when the automobile stops traveling or when the temperature in the fuel tank rises due to an increase in temperature or the like. When gasoline fuel is supplied, fuel vapor filled in the fuel tank is pushed out by the fuel supply fuel. The fuel vapor pushed out from the fuel tank is adsorbed by the canister and is prevented from being released into the atmosphere.

  Further, a part of the air supplied to the engine is sent through the canister using the negative pressure generated in the intake manifold. At this time, the fuel vapor adsorbed by the canister is desorbed and carried to the engine as purge air together with air. Thus, the canister repeats the adsorption and desorption of the fuel vapor between the fuel tank and the engine.

  In recent years, environmental regulations have been strengthened, and it has been required to reduce the amount of fuel vapor discharged. Therefore, it is conceivable to use a canister having high adsorption / desorption performance, but this leads to an increase in the size of the canister and high cost. Further, in the hybrid vehicle of the engine and the motor, the loss of the purge opportunity due to the recent improvement of the engine efficiency is increased, and the purge opportunity itself using the negative pressure of the intake manifold itself due to the existence of the engine stop. Less. This also causes a need for a canister having high adsorption / desorption performance.

  Here, in the fluid pushed out from the fuel tank, liquid fuel may mix with the fuel vapor. In this case, a gas-liquid two-phase flow of fuel is sent from the fuel tank to the canister. Therefore, by providing a gas-liquid separator in the passage connecting the fuel tank and the canister, it is possible to reduce the size of the canister by preventing liquid fuel from being sent to the canister (Patent Document). 1, 2).

Japanese Patent No. 5844661 Japanese Patent Laid-Open No. 2001-3818

  The present invention effectively prevents the liquid fuel from being sent to the canister by adopting a new configuration different from the conventional configuration for separating the gas-liquid two-phase flow of the fuel into the liquid fuel and the fuel vapor. It is an object of the present invention to provide a gas-liquid separator that can be used.

  A gas-liquid separation device according to the present invention is a gas-liquid separation device provided in a passage connecting a fuel tank and a canister, and is located in an internal space and an upper portion, and from the fuel tank, a gas-liquid separation of fuel. A housing inlet for flowing a phase flow into the internal space, a housing steam outlet for discharging the separated fuel vapor from the internal space, and a liquid fuel positioned at the lower portion and separated from the internal space. A housing having a housing liquid outlet for discharging, and a plurality of through holes that are disposed in the internal space of the housing and communicate with the housing vapor outlet and the housing liquid outlet located at the lower portion from the housing inlet located at the upper portion A base member comprising: a plurality of through holes; and inner peripheral surfaces of the plurality of through holes. And a plurality of shaft members forming a gas-liquid separation chamber by a radial clearance.

  Each of the gas-liquid separation chambers is formed on the housing inlet side, and has a first region into which the gas-liquid two-phase flow flows, and a channel cross-sectional area that is disposed downstream of the first region and is larger than the first region. The liquid fuel is formed on at least one of the inner peripheral surface of the through hole and the outer peripheral surface of the shaft member, which is provided in parallel with the enlarged space portion and that guides the fuel vapor. And a second region including a groove-shaped guide portion that guides to the lower portion while being attached by tension.

  As described above, the gas-liquid separation chamber includes the first region and the second region. The enlarged space of the second region has a larger channel cross-sectional area than the first region, so that the fuel vapor contained in the gas-liquid two-phase flow of the fuel flowing into the first region is separated from the gas-liquid two-phase flow. To the enlarged space of the second area. Further, the liquid fuel remaining after the fuel vapor is separated from the gas-liquid two-phase flow is guided by the groove-shaped guide portion provided in the enlarged space portion. This is because the surface tension of the liquid fuel keeps the fuel vapor from adhering to the groove-shaped guiding portion without moving to the enlarged space portion.

  As described above, the gas-liquid two-phase flow of the fuel can be separated into the fuel vapor and the liquid fuel by the gas-liquid separation chamber formed in the radial gap between the through hole of the base member and the shaft member. Furthermore, the base member includes a plurality of through holes, and each of the plurality of shaft members is inserted into each of the plurality of through holes. Accordingly, a large number of gas-liquid separation chambers are formed in the internal space of the housing, and the gas-liquid two-phase flow of the fuel flowing in from the fuel tank can be more effectively separated into the fuel vapor and the liquid fuel. it can. As a result, liquid fuel can be prevented from being sent to the canister. Therefore, the canister can be downsized. That is, the canister can be reduced in size even in an automobile driven by an engine alone or even in a hybrid automobile.

It is a whole lineblock diagram of a fuel line. It is an enlarged view of the gas-liquid separator of FIG. The vertical direction in the figure matches the vertical direction of the gravity direction. FIG. 3 is a sectional view taken along line III-III in FIG. 2. It is IV-IV sectional drawing of FIG. It is an enlarged view of one gas-liquid separation chamber of the first example. It is an enlarged view of the VI-VI cross section of FIG. It is an enlarged view of the VII-VII cross section of FIG. It is an enlarged view of one gas-liquid separation chamber of a 2nd example.

(1. Configuration of fuel line 1)
The overall configuration of the automobile fuel line 1 will be described with reference to FIG. In FIG. 1, a solid line arrow indicates liquid fuel, and a broken line arrow indicates fuel vapor. The fuel line 1 includes a fuel supply port 11, a fuel tank 12, a filler pipe 13 that supplies fuel from the fuel supply port 11 to the fuel tank 12, and a breather pipe 14 that recirculates fuel vapor from the fuel tank 12 to the fuel supply port 11. The fuel line 1 includes a feed pipe 15 that supplies fuel from the fuel tank 12 to the engine 16.

  Further, the fuel line 1 includes a canister 17, an evaporation pipe 18 (first evaporation pipe 18 a and a second evaporation pipe 18 b) that is a passage connecting the fuel tank 12 and the canister 17, and a purge that connects the canister 17 and the engine 16. A gas-liquid separator 20 provided in the pipe 19 and the evaporation pipe 18 is provided. Although not shown, each pipe is provided with a valve, a pump, or the like.

  The gas-liquid separator 20 is fed from the upper space in the fuel tank 12 by the refueling of the fuel from the refueling port 11 and the like through the first evaporative pipe 18a that is a part of the upstream side of the evaporative pipe 18. A gas-liquid two-phase flow of fuel consisting of fuel vapor and liquid fuel is introduced. The gas-liquid separator 20 separates the gas-liquid two-phase flow of fuel into fuel vapor and liquid fuel.

  Then, the gas-liquid separator 20 sends the separated fuel vapor to the canister 17 via the second evaporation pipe 18b which is a part of the remaining downstream side of the evaporation pipe 18. The canister 17 adsorbs the fuel vapor discharged from the gas-liquid separator 20. The fuel vapor adsorbed by the canister 17 is desorbed from the canister 17 by the air supplied to the engine 16, and is sent to the engine 16 as purge air through the purge pipe 19. On the other hand, the gas-liquid separator 20 returns the liquid fuel separated via the liquid return pipe 21 to the fuel tank 12.

(2. Overall configuration of gas-liquid separator 20)
The overall configuration of the gas-liquid separator 20 will be described with reference to FIGS. The gas-liquid separation device 20 includes a housing 30, a base member 40, a shaft member unit 50, and a cloth 60.

  The housing 30 is formed by laminating a plurality of types of resin materials. Similar to the fuel tank 12, the housing 30 has fuel permeation resistance and the like. The housing 30 may have the same configuration as the fuel tank 12 or a different configuration. The housing 30 includes an internal space 31, a housing inlet 32 connected to the first evaporation pipe 18a, a housing vapor outlet 33 connected to the second evaporation pipe 18b, and a housing liquid outlet 34 connected to the liquid return pipe 21.

  The internal space 31 includes an upper diffusion layer 31a, a cloth arrangement layer 31b, a gas-liquid separation layer 31c, a lower diffusion layer 31d, and a liquid induction layer 31e from the upper side to the lower side. Each layer 31a-31e exists over the whole area | region of the horizontal direction of the internal space 31 in each height range. The upper diffusion layer 31a is a region that does not have a partition member in the horizontal direction, and is a region in which the gas-liquid two-phase flow that flows in can freely diffuse. The cloth arrangement layer 31b is an area in which a cloth 60 described later is arranged. The gas-liquid separation layer 31c is a region that separates the gas-liquid two-phase flow into fuel vapor and liquid fuel.

  The lower diffusion layer 31d is a region that does not have a partition member in the horizontal direction, and is a region where the separated fuel vapor can freely diffuse. The lower diffusion layer 31d also functions as a region where the separated liquid fuel is dropped toward the lower surface of the housing 30. The liquid guide layer 31 e is a region that guides the separated liquid fuel to the housing liquid outlet 34. The liquid guide layer 31e is formed in, for example, a funnel shape, and can guide liquid fuel from a wide upper opening toward a narrow opening which is a housing liquid outlet 34 positioned below.

  The housing inlet 32 is located at the upper part of the housing 30 and flows a gas-liquid two-phase flow of fuel from the fuel tank 12 into the internal space 31 through the first evaporation pipe 18a. As shown in FIG. 2, the housing inlet 32 may be formed on the upper surface of the housing 30, or may be formed on the side surface of the upper portion of the housing 30 although not shown. That is, the housing inlet 32 is continuous with the upper diffusion layer 31 a of the internal space 31.

  The housing vapor outlet 33 is located below the housing 30 and discharges the fuel vapor separated in the internal space 31 from the internal space 31 to the canister 17 through the second evaporation pipe 18b. As shown in FIG. 2, the housing steam outlet 33 is formed on the side surface of the lower portion of the housing 30. The housing vapor outlet 33 is provided at the same height as the lower diffusion layer 31 d of the internal space 31. That is, the housing vapor outlet 33 is continuous with the lower diffusion layer 31d.

  The housing liquid outlet 34 is located at the lower part of the housing 30 and discharges the liquid fuel separated in the internal space 31 from the internal space 31 to the fuel tank 12 via the liquid return pipe 21. The housing liquid outlet 34 is formed in the lower surface of the lower part of the housing 30, as shown in FIG. That is, the housing liquid outlet 34 is continuous with the liquid guide layer 31 e that is the lowermost region of the internal space 31.

  The base member 40 is formed of a resin and has a substantially rectangular parallelepiped block shape. The outer peripheral surface (side surfaces other than the upper and lower surfaces) of the base member 40 has a shape corresponding to the inner wall surface of the gas-liquid separation layer 31 c of the housing 30. The base member 40 is disposed in the gas-liquid separation layer 31c of the housing 30, and there is no gap between the outer peripheral surface of the base member 40 and the inner wall surface of the gas-liquid separation layer 31c of the housing 30. , So that it has a slight gap.

  As shown in FIG. 2, the base member 40 includes a plurality of through holes 41 penetrating in the vertical direction (equal to the vertical direction in FIG. 2). As shown in FIGS. 2 to 4, in this embodiment, an example in which the base member 40 includes 25 through holes 41 is shown. That is, the upper openings of the plurality of through holes 41 are located on the housing inlet 32 side, and the lower openings are located on the housing vapor outlet 33 and housing liquid outlet 34 side. Accordingly, the plurality of through holes 41 communicate from the housing inlet 32 located at the upper part to the housing vapor outlet 33 and the housing liquid outlet located at the lower part. Note that the lower surface of the base member 40 forms a boundary between the gas-liquid separation layer 31 c and the lower diffusion layer 31 d in the internal space 31.

  The shaft member unit 50 includes a plurality of shaft members 51, a connecting member 52, and a height positioning member 53. Each shaft member 51 is inserted into each through hole 41. A part of the upper end side of the shaft member 51 projects upward from the inlet opening of the through hole 41. Further, a part on the lower end side of the shaft member 51 protrudes downward from the outlet opening of the through hole 41. That is, a part of the lower end side of the shaft member 51 exists in the lower diffusion layer 31d. Each shaft member 51 forms a gas-liquid separation chamber 70 by a radial gap with the inner peripheral surface of each through hole 41. The gas-liquid separation chamber 70, which is a radial gap between the outer peripheral surface of the shaft member 51 and the inner peripheral surface of the through hole 41, is formed over the entire length of the through hole 41.

  The connecting member 52 connects the upper ends of the plurality of shaft members 51 to each other. The connection member 52 is formed in a lattice shape when viewed from above, and has a structure capable of communicating the upper region of the connection member 52 and the lower region of the connection member 52. The height positioning member 53 extends downward from the lower surface of the connecting member 52 and is supported on the upper surface of the base member 40. That is, when the height positioning member 53 is supported by the base member 40, the relative position in the vertical direction between each shaft member 51 and the through hole 41 is positioned at a desired position.

  The cloth 60 is formed of a sheet-like nonwoven fabric or woven cloth. The cloth 60 is made of felt, for example. The cloth 60 is arranged on the cloth arrangement layer 31 b of the internal space 31. That is, the cloth 60 is disposed between the upper diffusion layer 31a and the base member 40 in the vertical direction. The cloth 60 has a function of reducing the flow velocity of the gas-liquid two-phase flow that passes therethrough. That is, the cloth 60 reduces the flow velocity of the gas-liquid two-phase flow diffused in the upper diffusion layer 31a. Therefore, in the gas-liquid two-phase flow, the flow velocity after passing through the cloth 60 is lower than the flow velocity of the gas-liquid two-phase flow before passing through the cloth 60.

(3. Flow of fluid in gas-liquid separator 20)
A gas-liquid two-phase flow of fuel reaches the housing inlet 32 from the fuel tank 12 via the first evaporation pipe 18 a and flows into the upper diffusion layer 31 a of the internal space 31. The gas-liquid two-phase flow that has flowed into the upper diffusion layer 31a diffuses in the horizontal direction of the internal space 31 in the upper diffusion layer 31a. Since there is no member such as a partition member in the upper diffusion layer 31a, the gas-liquid two-phase flow that has flowed in can be freely diffused. Therefore, even when the housing inlet 32 is narrow, the gas-liquid two-phase flow can be reliably diffused in the horizontal direction by the upper diffusion layer 31a.

  The cloth arrangement layer 31b is continuously located downstream (downward in the direction of gravity) of the upper diffusion layer 31a. And the gas-liquid two-phase flow which flowed into upper diffusion layer 31a passes cloth 60 arranged at cloth arrangement layer 31b. The cloth 60 is arranged over the entire horizontal range of the internal space 31 of the housing 30. The cloth 60 has a function of reducing the flow velocity of the gas-liquid two-phase flow. Therefore, the gas-liquid two-phase flow diffused in the horizontal direction in the upper diffusion layer 31 a passes through the cloth 60, and the flow velocity is reduced.

  The gas-liquid separation layer 31c is continuously located downstream (downward in the direction of gravity) of the cloth arrangement layer 31b. A base member 40 and a shaft member unit 50 are disposed in the gas-liquid separation layer 31c. Therefore, the gas-liquid two-phase flow that has passed through the cloth 60 flows into the gas-liquid separation chamber 70 that is a radial gap between the plurality of through holes 41 of the base member 40 and the plurality of shaft members 51. That is, by arranging the upper diffusion layer 31a and the cloth 60 between the housing inlet 32 and the gas-liquid separation chamber 70 in the vertical direction, a gas-liquid two-phase flow in a state where the gas is diffused in the horizontal direction and the flow velocity is reduced. Then, it flows into the plurality of gas-liquid separation chambers 70. Therefore, the gas-liquid two-phase flow can flow uniformly into the plurality of gas-liquid separation chambers 70.

  The gas-liquid two-phase flow moves downward in the gas-liquid separation chamber 70, whereby the gas-liquid two-phase flow is separated into fuel vapor and liquid fuel in the gas-liquid separation chamber 70. Since the gas-liquid two-phase flow flowing into the plurality of gas-liquid separation chambers 70 has a reduced flow velocity, the gas-liquid separation function can be more effectively exhibited. Furthermore, since the gas-liquid two-phase flow uniformly flows into the plurality of gas-liquid separation chambers 70, each of the plurality of gas-liquid separation chambers 70 can reliably exhibit the gas-liquid separation function. That is, the gas-liquid separation function of the plurality of gas-liquid separation chambers 70 as a whole is in a very high state.

  A lower diffusion layer 31d is continuously located downstream (downward in the direction of gravity) of the gas-liquid separation layer 31c. Although the base member 40 does not exist in the lower diffusion layer 31d, a part of the lower end side of the plurality of shaft members 51 exists. However, the lower diffusion layer 31d is not partitioned by the shaft member 51. Therefore, the fuel vapor separated by the gas-liquid separation chamber 70 can be diffused in the horizontal direction in the lower diffusion layer 31d. Furthermore, the liquid fuel separated by the gas-liquid separation chamber 70 can fall from the base member 40 in the lower diffusion layer 31d.

  The liquid guide layer 31e is continuously located downstream (lower in the gravity direction) of the lower diffusion layer 31d. Since the liquid guide layer 31e is formed in a funnel shape, the liquid fuel dropped on the lower surface of the internal space 31 is guided by the funnel-shaped liquid guide layer 31e toward the housing liquid outlet 34 located below. Be guided. Thus, the separated liquid fuel is discharged from the housing liquid outlet 34 without staying in the internal space 31. The liquid fuel discharged from the housing liquid outlet 34 is returned to the fuel tank 12 via the liquid return pipe 21.

  The fuel vapor separated by the gas-liquid separation chamber 70 is diffused in the lower diffusion layer 31d as described above. Here, the fuel vapor that has escaped from the gas-liquid separation chamber 70 is the lower diffusion layer 31d positioned relatively upward in the lower region of the base member 40 (the lower diffusion layer 31d and the liquid guide layer 31e) in the internal space 31. It is easy to exist in the state. A housing vapor outlet 33 is provided on the side of the lower diffusion layer 31d. That is, the fuel vapor separated in the gas-liquid separation chamber 70 is diffused in the lower diffusion layer 31d and then discharged from the housing vapor outlet 33 to the second evaporation pipe 18b. The fuel vapor discharged to the second evaporation pipe 18 b is adsorbed by the canister 17.

(4. Configuration and operation of gas-liquid separation chamber 70 of the first example)
Next, the structure of the gas-liquid separation chamber 70 of a 1st example is demonstrated with reference to FIGS. As shown in FIG. 5, the gas-liquid separation chamber 70 is formed by a radial gap between the inner peripheral surface of the through hole 41 and the outer peripheral surface of the shaft member 51. That is, the gas-liquid separation chamber 70 is formed so as to extend in the vertical direction (gravity direction).

  First, the gas-liquid separation chamber 70 will be described from the shape side. As shown in FIG. 5 to FIG. 7, the inner peripheral surface of the through hole 41 has grooves 41 a that extend in the through direction and are formed in the circumferential direction over the entire length of the through hole 41. 6 and 7, thirty grooves 41 a are formed in the through hole 41. The groove 41 a is formed so as to increase the groove width toward the radially inner side of the through hole 41, and is formed so as to decrease the groove width toward the radially outer side of the through hole 41. However, the groove width of the groove 41 a may be the same in the radial direction of the through hole 41. The inscribed circle of the groove 41 a of the through hole 41 is the same in the through direction of the through hole 41 over the entire length of the through hole 41. On the other hand, the outer peripheral surface of the shaft member 51 is formed in a tapered shape whose diameter decreases from the upper side to the lower side. The radial cross section of the outer peripheral surface of the shaft member 51 is a circle. Therefore, the radial clearance between the inscribed circle of the groove 41a of the through hole 41 and the outer peripheral surface of the shaft member 51 is narrower toward the upper side of the through hole 41 as shown in FIG. 6, and the through hole is shown in FIG. The area below 41 is wider.

  Next, the gas-liquid separation chamber 70 will be described from a functional aspect. The gas-liquid separation chamber 70 includes a first region 71 formed on the upper side, that is, on the housing inlet 32 side, and a second region 72 formed on the lower side, that is, on the housing vapor outlet 33 and the housing liquid outlet 34 side. The second region 72 includes an enlarged space portion 72a and a groove-shaped guide portion 72b. That is, in the gas-liquid separation chamber 70, the gas-liquid two-phase flow flows into the narrow first region 71 and is divided from the first region 71 into the enlarged space portion 72a and the groove-shaped guide portion 72b.

  That is, in the downstream of the first region 71 that is a narrow space, there is an enlarged space portion 72a in which the space expands and a groove-shaped guide portion 72b in which the narrow space is maintained. In this case, the fuel vapor in the gas-liquid two-phase flow flowing into the first region 71 is guided to the enlarged space portion 72a, whereas the liquid fuel in the gas-liquid two-phase flow is in a narrow space. It will be in the state adhering to a certain groove-shaped guide part 72b. Thus, by providing the narrow first region 71 and the enlarged space portion 72a and the groove-shaped guide portion 72b on the downstream side of the first region 71, the gas-liquid two-phase flow is separated into fuel vapor and liquid fuel. Is done.

  This will be described in more detail below. The first region 71 flows in a gas-liquid two-phase flow that is diffused in the horizontal direction by the upper diffusion layer 31 a and whose flow velocity is reduced by the cloth 60. The first region 71 is a region having a very small channel cross-sectional area. Specifically, as shown in FIG. 6, the first region 71 is constituted by a radial gap between the groove 41 a of the through hole 41 and the tapered large-diameter side portion of the shaft member 51. In the first region 71, the radial annular gap between the inscribed circle of the groove 41a of the through hole 41 and the tapered large-diameter side portion of the shaft member 51 is smaller than the channel cross-sectional area of the groove 41a. . Accordingly, the first region 71 is substantially a region formed by the groove 41a. Thus, the first region 71 is a very narrow region.

  The second region 72 constitutes most of the lower portion of the through hole 41 as compared with the first region 71. The second region 72 is constituted by a radial gap between the groove 41 a of the through hole 41 and the tapered small diameter side portion of the shaft member 51. As described above and as shown in FIG. 5, the second region 72 includes the enlarged space portion 72 a and the groove-shaped guide portion 72 b.

  As shown in FIG. 5, the enlarged space portion 72 a is disposed on the downstream side of the first region 71. As shown in FIG. 7, the enlarged space portion 72 a is configured by a radial annular gap between the inscribed circle of the groove 41 a of the through hole 41 and the tapered small diameter side portion of the shaft member 51. The shaft member 51 is formed in a tapered shape that decreases in diameter downward. Therefore, the enlarged space portion 72a is formed to have a larger annular gap as it goes downward.

  And in the expansion space part 72a, it has a flow-path cross-sectional area larger than the 1st area | region 71 in the downward side. That is, when going from the first region 71 to the enlarged space portion 72a of the second region 72, the flow path cross-sectional area is enlarged. In particular, in the present embodiment, the channel cross-sectional area gradually increases. Therefore, the enlarged space portion 72a can separate the fuel vapor contained in the gas-liquid two-phase flow and guide it to the lower diffusion layer 31d.

  As shown in FIG. 5, the groove-shaped guide part 72b is arranged in parallel in the enlarged space part 72a. The groove-shaped guiding portion 72 b is configured by the groove 41 a of the through hole 41 that faces the tapered small-diameter side portion of the shaft member 51. Each groove 41a constituting the groove-shaped guiding portion 72b has a smaller flow path cross-sectional area than the enlarged space portion 72a. Therefore, the liquid fuel adheres to the groove-shaped guiding portion 72b due to surface tension. That is, the groove-shaped guiding part 72b can separate the liquid fuel contained in the gas-liquid two-phase flow that has flowed into the first region 71 and guide the liquid fuel to the lower diffusion layer 31d while adhering the liquid fuel.

  Therefore, the gas-liquid two-phase flow of the fuel can be reliably separated into the fuel vapor and the liquid fuel by the gas-liquid separation chamber 70 formed in the radial gap between the through hole 41 of the base member 40 and the shaft member 51. it can. Further, the base member 40 includes a plurality of through holes 41, and each of the plurality of shaft members 51 is inserted into each of the plurality of through holes 41. Accordingly, a large number of gas-liquid separation chambers 70 are formed in the internal space 31 of the housing 30, and the gas-liquid two-phase flow of the fuel flowing in from the fuel tank 12 is more effectively converted into fuel vapor and liquid fuel. Can be separated. As a result, liquid fuel can be prevented from being sent to the canister 17. Therefore, the canister 17 can be downsized. That is, the canister 17 can be downsized in both a car driven by the engine 16 and a hybrid car.

(5. Configuration of gas-liquid separation chamber 170 of the second example)
The configuration of the gas-liquid separation chamber 170 of the second example will be described with reference to FIG. As shown in FIG. 8, the shaft member 51 includes a large-diameter portion 51a and a small-diameter portion 51b provided through a step with respect to the large-diameter portion 51a. That is, the large diameter part 51a is located above the shaft member 51, and the small diameter part 51b is located below. The first region 71 is constituted by a radial gap between the groove 41a of the through hole 41 and the large diameter portion 51a. The second region 72 is configured by a radial gap between the groove 41a of the through hole 41 and the small diameter portion 51b. The enlarged space portion 72a of the second region 72 is a radial annular gap between the inscribed circle of the groove 41a of the through hole 41 and the small diameter portion 51b. The groove-shaped guide part 72b of the second region 72 is configured by the groove 41a of the through hole 41 facing the small diameter part 51b. Also in this case, the same effect as the gas-liquid separation chamber 70 of the first example is achieved. In the gas-liquid separation chamber 170 of the second example, the flow passage cross-sectional area is rapidly enlarged when going from the first region 71 to the enlarged space portion 72a of the second region 72.

(6. Others)
In the above embodiment, the radial cross section of the outer peripheral surface of the shaft member 51 is circular. However, the present invention is not limited to this, and a groove may be formed on the outer peripheral surface of the shaft member 51 as in the case of the through hole 41. In this case, a plurality of grooves extending in the penetration direction are formed on the inner circumferential surface of the through hole 41 and the outer circumferential surface of the shaft member 51. Further, the radial annular gap between the inscribed circle of the groove of the through hole 41 and the circumscribed circle of the groove of the shaft member 51 becomes larger downward. In this case, the area to which the liquid fuel is attached is increased. A plurality of grooves may be formed on the outer peripheral surface of the shaft member 51, and the radial cross section of the inner peripheral surface of the through hole 41 may be circular.

DESCRIPTION OF SYMBOLS 1: Fuel line 11: Refueling port 12: Fuel tank 13: Filler piping 14: Breather piping 15: Feed piping 16: Engine 17: Canister 18: Evaporation piping 18a: First evaporation piping 18b: Second evaporation pipe, 19: Purge pipe, 20: Gas-liquid separator, 21: Liquid return pipe, 30: Housing, 31: Internal space, 31a: Upper diffusion layer, 31b: Cloth arrangement layer, 31c: Gas-liquid Separation layer, 31d: Lower diffusion layer, 31e: Liquid induction layer, 32: Housing inlet, 33: Housing vapor outlet, 34: Housing liquid outlet, 40: Base member, 41: Through hole, 41a: Groove, 50: Shaft member Unit 51: shaft member 51a: large diameter part 51b: small diameter part 52: connecting member 53: height positioning member 6 : Cloth, 70, 170: gas-liquid separation chamber, 71: first region, 72: second region, 72a: enlarged space portion, 72b: groove guiding section

Claims (8)

A gas-liquid separation device provided in a passage connecting a fuel tank and a canister,
An internal space, a housing inlet located in the upper part and housing a gas-liquid two-phase flow of fuel from the fuel tank into the inner space, and a housing vapor located in the lower part and discharging separated fuel vapor from the inner space A housing having an outlet and a housing liquid outlet located in the lower portion and discharging the separated liquid fuel from the internal space;
A base member that is disposed in the internal space of the housing and includes a plurality of through holes communicating with the housing vapor outlet and the housing liquid outlet located at the lower part from the housing inlet located at the upper part;
A plurality of shaft members that are respectively inserted into the plurality of through holes and that form a gas-liquid separation chamber by a radial gap with an inner peripheral surface of the plurality of through holes;
With
Each of the gas-liquid separation chambers
A first region that is formed on the housing inlet side and flows in the gas-liquid two-phase flow;
An enlarged space portion that is disposed downstream of the first region and has a flow passage cross-sectional area larger than that of the first region, and that guides the fuel vapor, and is arranged in parallel with the enlarged space portion, A second region having a groove-shaped guiding portion formed on at least one of the peripheral surface and the outer peripheral surface of the shaft member and guiding the liquid fuel to the lower portion while being attached by surface tension;
A gas-liquid separator.   The internal space of the housing has an upper diffusion layer for diffusing the gas-liquid two-phase flow flowing from the housing inlet between the plurality of gas-liquid separation chambers and the housing inlet in the vertical direction. The gas-liquid separator described in 1. The gas-liquid separator further includes:
A cloth disposed in the internal space of the housing and configured to reduce the flow velocity of the gas-liquid two-phase flow diffused in the upper diffusion layer between the plurality of gas-liquid separation chambers and the upper diffusion layer in the vertical direction; The gas-liquid separation device according to claim 2, comprising: The housing steam outlet is provided on a side surface of the lower portion of the housing;
The gas-liquid separator according to any one of claims 1 to 3, wherein the housing liquid outlet is provided on a lower surface of the lower portion of the housing. The internal space of the housing further includes:
5. The gas-liquid separator according to claim 4, further comprising a lower diffusion layer in which the fuel vapor diffuses between a plurality of gas-liquid separation chambers and the housing liquid outlet.   The gas-liquid separation device according to any one of claims 1 to 5, wherein the plurality of shaft members are connected to each other. The inner circumferential surface of the through hole has a plurality of grooves extending in the circumferential direction and extending in the circumferential direction over the entire length of the through hole,
The shaft member is formed in a taper shape whose diameter is reduced from above to below,
The first region is constituted by a radial gap between the groove of the through-hole and the tapered large-diameter side portion,
The second region is constituted by a radial gap between the groove of the through-hole and the tapered small-diameter side portion,
The enlarged space portion of the second region is constituted by a radial annular gap between the tapered small diameter side portion and the groove of the through hole,
The gas-liquid separation device according to any one of claims 1 to 6, wherein the groove-shaped guide portion of the second region is configured by the groove of the through hole facing the tapered small-diameter side portion. . The inner circumferential surface of the through hole has a plurality of grooves extending in the circumferential direction and extending in the circumferential direction over the entire length of the through hole,
The shaft member includes a large diameter portion, and a small diameter portion provided through a step with respect to the large diameter portion,
The first region is configured by a radial gap between the groove of the through hole and the large diameter portion,
The second region is constituted by a radial gap between the groove of the through hole and the small diameter portion,
The enlarged space portion of the second region is constituted by a radial annular gap between the small diameter portion and the groove of the through hole,
The gas-liquid separation device according to any one of claims 1 to 6, wherein the groove-shaped guide portion of the second region is configured by the groove of the through hole facing the small diameter portion.

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