JP7045779B2 - Gas-liquid separator - Google Patents

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 temperature inside the fuel tank rises when the automobile is stopped or when the temperature rises. When refueling gasoline fuel, the fuel vapor filled in the fuel tank is pushed out by the refueling fuel. The fuel vapor extruded from the fuel tank is adsorbed by the canister to prevent the fuel vapor from being released to the atmosphere.

Further, a part of the air supplied to the engine is sent through the canister by utilizing the negative pressure generated in the intake manifold. At this time, the fuel vapor adsorbed on the canister is desorbed and carried to the engine as purge air together with air. In this way, the canister repeatedly absorbs and desorbs fuel vapor between the fuel tank and the engine.

In recent years, environmental regulations have been tightened, and it is required to reduce fuel vapor emissions. Therefore, it is conceivable to use a canister having high suction / desorption performance, but this causes an increase in the size of the canister and increases the cost. Further, in a hybrid vehicle of an engine and a motor, the loss of purging opportunity due to the improvement of engine efficiency in recent years becomes large, and the purging opportunity itself using the negative pressure of the intake manifold due to the existence of the engine stopped. Is reduced. This is also the reason why a canister having high suction / desorption performance is required.

Here, liquid fuel may be mixed with the fuel vapor in the fluid extruded from the fuel tank. 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 separation device in the passage connecting the fuel tank and the canister, it is possible to reduce the size of the canister by preventing the liquid fuel from being sent to the canister (Patent Document). 1, 2).

Japanese Patent No. 5844661 Japanese Unexamined Patent Publication 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 as a 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 separation device capable of performing.

The 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 part and is a gas-liquid separation device for fuel from the fuel tank. A housing inlet that allows phase currents to flow into the internal space, a housing steam outlet that is located at the bottom and discharges separated fuel vapor from the internal space, and a liquid fuel that is located at the bottom and separated from the internal space. A housing having a housing liquid outlet to be discharged, and the housing steam outlet and the housing located in the lower part of the housing, which are arranged in the internal space of the housing and flow into the internal space from the housing inlet located at the upper part. A base member having a plurality of through holes to be circulated to the liquid outlet side and the plurality of through holes are each inserted, and a gas-liquid separation chamber is formed by a radial gap between the inner peripheral surfaces of the plurality of through holes. It is provided with a plurality of shaft members.

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

As mentioned above, the gas-liquid separation chamber comprises a first region and a second region. By making the flow path cross-sectional area larger than that of the first region in the expanded space of the second region, 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. And move to the expanded space part 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 induction portion provided in the expanded space portion. This is because the surface tension of the liquid fuel keeps the fuel vapor attached to the groove-shaped guide portion without moving to the expanded space portion.

In this way, 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. Further, the base member is provided with a plurality of through holes, and each of the plurality of shaft members is inserted into each of the plurality of through holes. Therefore, 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 from the fuel tank can be more effectively separated into the fuel vapor and the liquid fuel. can. As a result, it is possible to prevent the liquid fuel from being sent to the canister. Therefore, the size of the canister can be reduced. That is, it is possible to reduce the size of the canister in an automobile driven only by an engine and further in a hybrid automobile.

It is an overall block diagram of a fuel line. It is an enlarged view of the gas-liquid separation device of FIG. The vertical direction in the figure coincides with the vertical direction in the direction of gravity. FIG. 2 is a sectional view taken along line III-III of FIG. FIG. 2 is a sectional view taken along line IV-IV 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 the second example.

(1. Configuration of fuel line 1)
The overall configuration of the fuel line 1 of an automobile will be described with reference to FIG. In FIG. 1, solid arrows indicate liquid fuels and dashed arrows indicate fuel vapors. The fuel line 1 includes a refueling port 11, a fuel tank 12, a filler pipe 13 for supplying fuel from the refueling port 11 to the fuel tank 12, and a breather pipe 14 for recirculating fuel steam from the fuel tank 12 to the refueling port 11 side. 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 evaporator pipe 18 (first evaporator pipe 18a and a second evaporator pipe 18b) which is a passage connecting the fuel tank 12 and the canister 17, and a purge connecting the canister 17 and the engine 16. The gas-liquid separation device 20 provided in the pipe 19 and the evaporator pipe 18 is provided. Although not shown, valves, pumps, and the like are provided in each pipe.

The gas-liquid separation device 20 is connected to the gas-liquid separation device 20 from the upper space in the fuel tank 12 via the first evaporator pipe 18a, which is a part of the upstream side of the evaporator pipe 18, by refueling from the fuel filler port 11. A gas-liquid two-phase flow of fuel consisting of fuel vapor and liquid fuel flows in. The gas-liquid separation device 20 separates the gas-liquid two-phase flow of fuel into fuel vapor and liquid fuel.

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

(2. Overall configuration of gas-liquid separation device 20)
The overall configuration of the gas-liquid separation device 20 will be described with reference to FIGS. 2 to 4. 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. Like 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 may have a different configuration. The housing 30 includes an internal space 31, a housing inlet 32 connected to the first evaporator pipe 18a, a housing vapor outlet 33 connected to the second evaporator 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. The layers 31a-31e are present over the entire horizontal region of the interior space 31 in their respective height ranges. The upper diffusion layer 31a is a region having no partition member in the horizontal direction, and is a region in which the inflowing gas-liquid two-phase flow can freely diffuse. The cloth arrangement layer 31b is an area where the cloth 60, which will be described later, is arranged. The gas-liquid separation layer 31c is a region for separating the gas-liquid two-phase flow into fuel vapor and liquid fuel.

The lower diffusion layer 31d is a region having no partition member in the horizontal direction, and is a region in which the separated fuel vapor can be freely diffused. The lower diffusion layer 31d also functions as a region for dropping the separated liquid fuel toward the lower surface of the housing 30. The liquid induction layer 31e is a region for guiding the separated liquid fuel to the housing liquid outlet 34. The liquid induction layer 31e is formed, for example, in a funnel shape, and can guide the liquid fuel from the wide opening above to the narrow opening which is the housing liquid outlet 34 located below.

The housing inlet 32 is located at the upper part of the housing 30, and the gas-liquid two-phase flow of fuel flows from the fuel tank 12 into the internal space 31 via the first evaporator 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 31a of the internal space 31.

The housing steam outlet 33 is located at the lower part of the housing 30, and discharges the fuel vapor separated in the internal space 31 from the internal space 31 to the canister 17 via the second evaporator pipe 18b. The housing steam outlet 33 is formed on the lower side surface of the housing 30, as shown in FIG. The housing steam outlet 33 is provided at the same height as the lower diffusion layer 31d of the internal space 31. That is, the housing steam 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 on the lower surface of the lower portion of the housing 30, as shown in FIG. That is, the housing liquid outlet 34 is continuous with the liquid induction layer 31e, which is the lowest region of the internal space 31.

The base member 40 is molded of resin and is formed in a substantially rectangular parallelepiped block-shaped outer shape. The outer peripheral surface (side surface 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 31c of the housing 30. The base member 40 is arranged in the gas-liquid separation layer 31c of the housing 30, and is there a 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? , It will have 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, the present embodiment shows an example in which the base member 40 includes 25 through holes 41. That is, the upper opening of the plurality of through holes 41 is located on the housing inlet 32 side, and the lower opening is located on the housing vapor outlet 33 and the housing liquid outlet 34 side. Therefore, the plurality of through holes 41 allow the fluid flowing into the internal space 31 from the housing inlet 32 located at the upper part to flow to the housing steam outlet 33 and the housing liquid outlet 34 side located at the lower part. The lower surface of the base member 40 constitutes a boundary between the gas-liquid separation layer 31c and the lower diffusion layer 31d 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 through 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 of the lower end side of the shaft member 51 projects 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. Then, 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 connecting member 52 is formed in a grid pattern when viewed from above, and has a structure capable of communicating the upper region of the connecting member 52 and the lower region of the connecting 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, by supporting the height positioning member 53 by the base member 40, the relative positions of the shaft members 51 and the through holes 41 in the vertical direction are positioned at desired positions.

The cloth 60 is formed of a sheet-shaped non-woven fabric or a woven cloth. The cloth 60 is formed of, for example, felt. The cloth 60 is arranged in the cloth arrangement layer 31b of the internal space 31. That is, the cloth 60 is arranged 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 passing through. That is, the cloth 60 reduces the flow velocity of the gas-liquid two-phase flow diffused in the upper diffusion layer 31a. Therefore, the flow velocity of the gas-liquid two-phase flow 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. Fluid flow in the gas-liquid separator 20)
The gas-liquid two-phase flow of fuel reaches the housing inlet 32 from the fuel tank 12 via the first evaporator pipe 18a, and flows into the upper diffusion layer 31a of the internal space 31. The gas-liquid two-phase flow that has flowed into the upper diffusion layer 31a diffuses in the upper diffusion layer 31a in the horizontal direction of the internal space 31. Since the upper diffusion layer 31a does not have any member such as a partition member, the inflowing gas-liquid two-phase flow 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 of the upper diffusion layer 31a (downward in the direction of gravity). Then, the gas-liquid two-phase flow flowing into the upper diffusion layer 31a passes through the cloth 60 arranged in the cloth arrangement layer 31b. The cloth 60 is arranged over the entire horizontal range of the interior 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 horizontally in the upper diffusion layer 31a passes through the cloth 60, and the flow velocity decreases.

The gas-liquid separation layer 31c is continuously located downstream of the cloth arrangement layer 31b (downward in the direction of gravity). A base member 40 and a shaft member unit 50 are arranged on 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, which 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 in the vertical direction between the housing inlet 32 and the gas-liquid separation chamber 70, the gas-liquid two-phase flow in a state where the upper diffusion layer 31a and the cloth 60 are diffused in the horizontal direction and the flow velocity is reduced can be obtained. , Flows into a plurality of gas-liquid separation chambers 70. Therefore, the gas-liquid two-phase flow can evenly flow into the plurality of gas-liquid separation chambers 70.

Then, the gas-liquid two-phase flow moves downward in the gas-liquid separation chamber 70, so that the gas-liquid two-phase flow is separated into the fuel vapor and the liquid fuel in the gas-liquid separation chamber 70. Since the flow velocity of the gas-liquid two-phase flow flowing into the plurality of gas-liquid separation chambers 70 is reduced, the gas-liquid separation function can be more effectively exhibited. Further, since the gas-liquid two-phase flow evenly flows into the plurality of gas-liquid separation chambers 70, each of the plurality of gas-liquid separation chambers 70 can surely exert 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.

The lower diffusion layer 31d is continuously located downstream of the gas-liquid separation layer 31c (downward in the direction of gravity). 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 in a state of being 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. Further, the liquid fuel separated by the gas-liquid separation chamber 70 can fall from the base member 40 at the lower diffusion layer 31d.

The liquid induction layer 31e is continuously located downstream of the lower diffusion layer 31d (downward in the direction of gravity). Since the liquid induction layer 31e is formed in a funnel shape, the liquid fuel that has fallen on the lower surface of the internal space 31 is guided by the funnel-shaped liquid induction layer 31e toward the housing liquid outlet 34 located below. Be guided. In this way, 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 located in the lower diffusion layer 31d relatively upward in the lower region (lower diffusion layer 31d and liquid induction layer 31e) of the base member 40 in the internal space 31. It becomes a state that tends to exist in. A housing steam 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 evaporator pipe 18b. The fuel vapor discharged to the second evaporator pipe 18b is adsorbed by the canister 17.

(4. Configuration and operation of the gas-liquid separation chamber 70 of the first example)
Next, the configuration of the gas-liquid separation chamber 70 of the first example will be described with reference to FIGS. 5 to 7. 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 aspect of shape. As shown in FIGS. 5 to 7, the inner peripheral surface of the through hole 41 has a plurality of grooves 41a extending in the through direction and formed in the circumferential direction over the entire length of the through hole 41. In FIGS. 6 and 7, 30 grooves 41a are formed in the through hole 41. The groove 41a is formed so as to widen the groove width toward the radial inward side of the through hole 41, and narrow the groove width toward the radial outward side of the through hole 41. However, the groove width of the groove 41a may be the same in the radial direction of the through hole 41. The inscribed circle of the groove 41a 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 is reduced 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 gap 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 as shown in FIG. It becomes wider toward the bottom of 41.

Next, the gas-liquid separation chamber 70 will be described from the functional aspect. The gas-liquid separation chamber 70 includes a first region 71 formed above, that is, on the housing inlet 32 side, and a second region 72 formed below, 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, the gas-liquid separation chamber 70 is divided into an enlarged space portion 72a and a groove-shaped induction portion 72b from the first region 71 by the gas-liquid two-phase flow flowing into the narrow first region 71.

That is, downstream of the first region 71, which 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 of the gas-liquid two-phase flow flowing into the first region 71 is guided to the expanded space 72a, whereas the liquid fuel of the gas-liquid two-phase flow is in a narrow space. It is in a state of being attached to a certain groove-shaped guide portion 72b. As described above, by providing the narrow first region 71 and the expanded 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 the fuel vapor and the liquid fuel. Will be done.

It will be described in more detail below. The first region 71 flows into a gas-liquid two-phase flow that is horizontally diffused by the upper diffusion layer 31a and whose flow velocity is reduced by the cloth 60. The first region 71 is a region where the cross-sectional area of the flow path is very small. Specifically, as shown in FIG. 6, the first region 71 is composed of a radial gap between the groove 41a of the through hole 41 and the tapered large-diameter side portion of the shaft member 51. Then, 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 flow path cross-sectional area of the groove 41a. .. Therefore, the first region 71 is substantially a region formed by the groove 41a. As described above, the first region 71 is a very narrow region.

The second region 72 constitutes most of the area below the through hole 41 as compared to the first region 71. The second region 72 is formed by a radial gap between the groove 41a 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 an enlarged space portion 72a and a groove-shaped guide portion 72b.

As shown in FIG. 5, the enlarged space portion 72a is arranged on the downstream side of the first region 71. Then, as shown in FIG. 7, the enlarged space portion 72a is composed of an annular gap in the radial direction between the inscribed circle of the groove 41a 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 whose diameter is reduced downward. Therefore, the enlarged space portion 72a is formed so as to become a large annular gap toward the lower side.

The lower side of the expanded space portion 72a has a flow path cross section larger than that of the first region 71. That is, the cross-sectional area of the flow path is expanded when going from the first region 71 to the expanded space portion 72a of the second region 72. In particular, in the present embodiment, the cross-sectional area of the flow path is gradually expanded. Therefore, the expanded 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 portion 72b is juxtaposed with the enlarged space portion 72a. The groove-shaped guide portion 72b is composed of a groove 41a of a through hole 41 facing the tapered small-diameter side portion of the shaft member 51. Each groove 41a constituting the groove-shaped guide portion 72b has a smaller flow path cross-sectional area than the enlarged space portion 72a. Therefore, the liquid fuel is in a state of being attached to the groove-shaped guide portion 72b due to surface tension. That is, the groove-shaped induction portion 72b can separate the liquid fuel contained in the gas-liquid two-phase flow flowing 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 separation chamber 70 formed in the radial gap between the through hole 41 of the base member 40 and the shaft member 51 can reliably separate the gas-liquid two-phase flow of the fuel into the fuel vapor and the liquid fuel. can. Further, the base member 40 is provided with 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. Therefore, 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 from the fuel tank 12 is more effectively converted into the fuel vapor and the liquid fuel. Can be separated. As a result, it is possible to prevent the liquid fuel from being sent to the canister 17. Therefore, the size of the canister 17 can be reduced. That is, the canister 17 can be miniaturized both in an automobile driven only by the engine 16 and further in a hybrid automobile.

(5. Configuration of the 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 with respect to the large diameter portion 51a via a step. That is, the large diameter portion 51a is located above the shaft member 51, and the small diameter portion 51b is located below. The first region 71 is formed by a radial gap between the groove 41a of the through hole 41 and the large diameter portion 51a. The second region 72 is composed of 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 portion 72b of the second region 72 is composed of a groove 41a of a through hole 41 facing the small diameter portion 51b. In this case as well, the same effect as that of the gas-liquid separation chamber 70 of the first example is obtained. In the gas-liquid separation chamber 170 of the second example, the cross-sectional area of the flow path is rapidly expanded when going from the first region 71 to the expanded 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. Not limited to this, a groove may be formed on the outer peripheral surface of the shaft member 51 as well as the through hole 41. In this case, a plurality of grooves extending in the penetration direction are formed on the inner peripheral surface of the through hole 41 and the outer peripheral 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 increases downward. In this case, the area to which the liquid fuel is attached becomes large. Further, 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.

1: Fuel line, 11: Refueling port, 12: Fuel tank, 13: Filler piping, 14: Breather piping, 15: Feed piping, 16: Engine, 17: Canister, 18: Evapo piping, 18a: First Evapo piping, 18b: Second Evapo pipe, 19: Purge pipe, 20: Gas / liquid separation device, 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 steam 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, 60: Cloth, 70, 170: Gas-liquid separation chamber, 71: First area, 72 : Second region, 72a: Enlarged space, 72b: Groove-shaped guide

Claims (8)

A gas-liquid separator installed in the passage connecting the fuel tank and the canister.
The housing steam located in the internal space and the upper part of the housing inlet where the gas-liquid two-phase flow of fuel flows into the internal space from the fuel tank, and the housing steam located in the lower part and discharging the separated fuel steam from the internal space. A housing with an outlet and a housing liquid outlet located at the bottom and draining the separated liquid fuel from the internal space.
A plurality of through holes arranged in the internal space of the housing and allowing the fluid flowing into the internal space from the housing inlet located at the upper part to flow to the housing vapor outlet and the housing liquid outlet side located at the lower part. With a base member and
A plurality of shaft members that are inserted into the plurality of through holes and form a gas-liquid separation chamber by a radial gap with the inner peripheral surface of the plurality of through holes.
Equipped with
Each gas-liquid separation chamber is
A first region formed on the inlet side of the housing and inflowing the gas-liquid two-phase flow,
An enlarged space portion that is arranged on the downstream side of the first region and has a larger flow path cross-sectional area than the first region to guide the fuel vapor, and a through hole that is juxtaposed in the expanded space portion. A second region having a groove-shaped guide 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 part while adhering the liquid fuel by surface tension.
A gas-liquid separator equipped with. The internal space of the housing has an upper diffusion layer for diffusing the gas-liquid two-phase flow flowing in from the housing inlet between the plurality of gas-liquid separation chambers and the housing inlet in the vertical direction.
The gas-liquid separation device according to claim 1 , wherein each of the gas-liquid separation chambers circulates the fluid diffused in the upper diffusion layer to the housing vapor outlet and the housing liquid outlet side . The gas-liquid separation device further
A cloth arranged in the internal space of the housing and reducing the flow velocity of the gas-liquid two-phase flow diffused in the upper diffusion layer is provided 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. The housing steam outlet is provided on the side surface of the lower portion of the housing.
The air-liquid separation device according to any one of claims 1-3, wherein the housing liquid outlet is provided on the lower surface of the lower portion of the housing. The interior space of the housing further
A lower diffusion layer through which the fuel vapor diffuses is provided between the plurality of gas-liquid separation chambers and the housing liquid outlet in the vertical direction.
The housing liquid outlet discharges the liquid fuel separated in the gas-liquid separation chamber and dropped in the lower diffusion layer.
The gas-liquid separation device according to claim 4, wherein the housing steam outlet discharges the fuel vapor separated in the gas-liquid separation chamber and diffused in the lower diffusion layer . 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 peripheral surface of the through hole has a groove extending in the through direction and a plurality of grooves formed in the circumferential direction over the entire length of the through hole.
The shaft member is formed in a tapered shape whose diameter is reduced from the upper side to the lower side.
The first region is composed of a radial gap between the groove of the through hole and the tapered large-diameter side portion.
The second region is composed of 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 composed of 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 1-6, wherein the groove-shaped guide portion in the second region is composed of the groove of the through hole facing the tapered small-diameter side portion. .. The inner peripheral surface of the through hole has a groove extending in the through direction and a plurality of grooves formed 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 with respect to the large-diameter portion via a step.
The first region is composed of a radial gap between the groove of the through hole and the large diameter portion.
The second region is composed of a radial gap between the groove of the through hole and the small diameter portion.
The expanded space portion of the second region is composed of 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 1-6, wherein the groove-shaped guide portion in the second region is composed of the groove of the through hole facing the small diameter portion.

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