JP2006069236A - Flow rate control valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flow rate control valve for sufficiently securing a gas flow passage. <P>SOLUTION: In the flow rate control valve, a liquid outlet part for making an inside of a housing communicate with an inflow opening is provided on a seat surface side part of a valve member, and thereby, liquid flowing into a space partitioned by the valve member and the housing flows from the liquid outlet part. Therefore, the liquid is prevented from being accumulated in the space, and the valve member stably operates. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a flow control valve used in a breather circuit of a fuel tank.

  A vaporized fuel recovery system called an evaporation circuit is provided in the vicinity of the fuel tank of the automobile. This evaporation circuit prevents vaporized fuel from being discharged to the outside air by guiding the vaporized fuel from the fuel tank to an external canister and adsorbing the vaporized fuel to activated carbon or the like for temporary storage. The canister is connected to the engine, and the vaporized fuel is discharged from the activated carbon by the intake negative pressure of the engine and mixed in the air-fuel mixture, so that the adsorbed vaporized fuel is used again as fuel.

  The evaporator circuit is generally provided with a breather tube that communicates the gas phase portion in the fuel tank and the outside air in order to reduce the intake of new air from the fuel filler port when the fuel tank is refueled. One end of the breather tube is connected to the vicinity of the fuel inlet of the inlet pipe, and the other end is inserted through a breather nipple fixed so as to communicate with the gas phase of the fuel tank. Vaporized fuel present in the fuel tank at the time of refueling is circulated from the breather nipple to the inlet pipe through the breather tube, so that entrainment of new air is reduced and vaporization of the fuel is suppressed. With this structure, the adsorption amount of the canister can be reduced. In general, an orifice for adjusting the breather gas amount is formed in the breather nipple so that the amount of breather gas circulated from the breather tube to the inlet pipe is not larger than the amount of air drawn in at the fuel filler opening.

  Hereinafter, the gas circulation circuit of the fuel tank → the breather nipple → the breather tube → the inlet pipe → the fuel tank is referred to as a breather circuit.

  Here, the oil supply speed when supplying fuel to the fuel tank is classified into two types, a low speed (representative value 15 L / min) and a high speed (representative value 38 L / min), depending on the specifications and usage of the fuel gun. And since the amount of air entrained is larger in high-speed oil supply, a larger amount of breather gas is required to circulate in the breather circuit during high-speed oil supply.

  In order to increase the amount of breather gas that circulates in the breather circuit during high-speed fueling, it is effective to increase the orifice opening. However, if the orifice opening is increased, the amount of breather gas that circulates in the breather circuit will increase even during low-speed refueling, and the breather gas flow rate will exceed the air entrainment amount in the range where the refueling speed is low. End up.

  Further, if the orifice opening is made small, vapor leak at the time of low-speed refueling can be prevented. However, if the orifice opening is made smaller, the difference between the amount of air entrained during high-speed refueling and the flow rate of the breather gas will increase, and the entrainment of new air will promote the vaporization of fuel in the tank and increase the amount of adsorption of the canister. End up. Due to such contradictory circumstances, the conventional breather circuit has a problem that it cannot cope with the increase or decrease in the required breather gas flow rate due to the increase or decrease in the oil supply speed.

In recent years, various apparatuses for solving this problem have been developed (for example, Patent Documents 1 and 2). Patent Document 1 proposes a fuel evaporative emission prevention device in which a breather circuit is provided with variable means for adjusting the amount of fuel evaporative gas circulation according to the pressure. Further, Patent Document 2 proposes that a connector with a built-in valve that adjusts the amount of fuel evaporative gas circulating according to pressure is arranged in a breather circuit.
Japanese Patent Laid-Open No. 08-216707 JP 2003-028010 A

  However, in the techniques described in these publications, since only a valve for opening and closing the flow path is provided, it is difficult to appropriately control the breather gas amount in both cases of low speed oil supply and high speed oil supply. This is because the conventional valve has a structure in which the valve opens as the gas pressure increases, and the breather gas flow rate gradually increases.

  The pressure of the breather gas circulating through the breather circuit (hereinafter simply referred to as gas pressure) is also greatly affected by temperature, and the gas pressure varies at low and high speeds. In order to cope with the variation in gas pressure, a breather gas with a constant flow rate should flow with respect to a relatively wide range of gas pressures at both low and high speeds, and a relatively narrow range of gas pressures. It is necessary to switch between the breather gas flow rate at low speed lubrication and the breather gas flow rate at high speed lubrication. That is, it is preferable that the breather gas flow rate and the gas pressure draw a steep S-curve when the breather gas flow rate is on the vertical axis and the gas pressure is on the horizontal axis. However, as described above, since the breather gas flow rate gradually increases as the gas pressure increases in the conventional valve, the breather gas flow rate during low-speed lubrication and the breather gas flow rate during high-speed lubrication due to a relatively narrow range of gas pressure changes. There is a problem that it is inferior in performance (hereinafter referred to as responsiveness to changes in gas pressure) and cannot cope with variations in gas pressure that occur during low-speed or high-speed oil supply.

  In order to solve these problems, the applicants of the present application have developed a flow control valve that can accurately cope with an increase or decrease in the required breather gas flow rate due to an increase or decrease in the oil supply speed. This flow control valve comprises a housing, a valve member, and an urging means, and controls the balance between opening and closing of the first valve portion and the second valve portion formed between the housing and the valve member, It flexibly supports high-speed and low-speed lubrication. Cross-sectional views schematically showing an example of the flow control valve are shown in FIGS. 7 to 9, and the operation of the flow control valve will be described.

  In this flow control valve, the housing 4 has an inflow opening 41 through which a fluid flows and an outflow opening 42 through which the fluid flowing in from the inflow opening flows out, as shown in FIG. The valve member 5 has a flange portion 51 projecting in the outer peripheral direction, and is movably disposed in the housing 4. The urging means 6 urges the valve member 5 in a direction approaching the inflow opening 41. In this flow control valve, a first valve portion 90 is provided between the valve member 5 and the housing 4, and a second valve portion 91 is formed between the flange portion of the valve member and the housing.

  As shown in FIG. 8, the first valve portion 90 is formed between the through hole 57 provided in the valve member 5 and the convex portion 33 constituting a part of the housing 4, and is away from the inflow opening 41. As the valve member 5 moves (hereinafter referred to as movement in the opening direction), the communication between the inflow opening 41 and the outflow opening 42 is gradually closed. As shown in FIG. 9, the second valve portion 91 is formed between the flange portion 51 provided on the valve member 5 and the cylindrical member 2 constituting a part of the housing 4, and the valve member 5 is opened. With the movement of the direction, communication between the inflow opening 41 and the outflow opening 42 is opened.

  In this flow control valve, when the fluid pressure on the inflow opening 41 side is equal to or less than a predetermined value, as shown in FIG. 7, the first valve portion 90 is opened and the second valve portion 91 is closed. Further, as shown in FIG. 8, when the valve member 5 moves in the opening direction due to an increase in the fluid pressure on the inflow opening 41 side, the opening area of the first valve portion 90 gradually narrows along with this movement. When the pressure difference between the inflow opening 41 and the outflow opening 42 exceeds a predetermined value, the second valve portion 91 opens the communication between the inflow opening 41 and the outflow opening 42 all at once, and as shown in FIG. The part 90 is closed and the second valve part 91 is open.

  According to this flow control valve, when the pressure difference between the inflow opening 41 and the outflow opening 42 is equal to or smaller than a predetermined value, that is, when the first valve portion 90 is in the open state, the fluid in the closed space flows in through the first valve portion 90. It flows from the opening 41 to the outflow opening 42 (in the direction of arrow a in FIG. 7). As the fluid pressure on the inflow opening 41 side increases, the opening area of the first valve portion 90 gradually decreases, the valve member 5 moves and the first valve portion 90 closes, and the inflow opening 41 and the outflow opening 42 When the pressure difference suddenly increases and exceeds a predetermined value, the valve member 5 moves in a direction away from the inflow opening 41 and the second valve portion 91 opens. At this time, the fluid in the housing 4 flows out from the inflow opening 41 through the second valve portion 91 (in the direction of arrow b in FIG. 9). For this reason, this flow control valve is excellent in responsiveness to changes in gas pressure, and when used in a breather circuit of a fuel tank, can flexibly cope with high-speed and low-speed oil supply.

  By the way, in the flow control valve shown in FIGS. 7 to 9, the valve member 5 is seated on the seat surface 43 of the housing 4 when the pressure on the inflow opening 41 side is equal to or less than a predetermined value. At this time, when liquid fuel flows into the housing through the outflow opening 42, the fuel may accumulate in the space 45 defined by the housing 4 and the valve member 5. If the fuel accumulated in the space 45 deteriorates or evaporates, the valve member 5 may adhere to the housing 4 and hinder the operation of the valve member 5. Further, when the fuel accumulated in the space 45 flows out to the breather tube through the outflow opening 42, the breather tube may be deteriorated due to the deterioration of the fuel.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a flow rate control valve capable of sufficiently securing a gas flow path.

The flow control valve of the present invention that solves the above-described problems includes a housing having an inflow opening through which a fluid flows in and an outflow opening through which the fluid that flows in from the inflow opening flows out to the outside, and a flange that protrudes in the outer peripheral direction. And a urging means for urging the valve member in a direction close to the inflow opening,
A first valve portion formed between the valve member and the housing and gradually closing the communication between the inflow opening and the outflow opening as the valve member moves in a direction away from the inflow opening, and between the flange portion and the housing A second valve part that opens and communicates with the inflow opening and the outflow opening as the valve member moves in a direction away from the inflow opening,
When the pressure on the inflow opening side is less than or equal to a predetermined value, the first valve portion is open and the second valve portion is closed, and when the pressure difference between the inflow opening side and the outflow opening exceeds a predetermined value, the second valve A flow rate control valve for a circulation line, wherein the portion is configured to open the communication between the inflow opening and the outflow opening at once,
The housing has a seating surface on which the valve member is seated when the pressure on the inflow opening side is a predetermined value or less,
The valve member has a liquid draining portion communicating with the inside of the housing and the inflow opening at a portion on the seat surface side.

  In the flow control valve of the present invention, the valve member has a substantially bottomed cylindrical shape with both ends open, the opening outer edge on the bottom side protrudes toward the other end, and the bottom is disposed in the housing with the bottom facing the seat surface. In the bottom portion, the portion near the inflow opening may have a second liquid draining portion that communicates the inside of the cylinder and the inflow opening.

  In the flow control valve of the present invention, the valve member has a substantially bottomed cylindrical shape with both ends open, and a part of the bottom part projects toward the other end side, and the bottom part is disposed in the housing with the seating surface facing the seat surface. The opening on the bottom side can be configured to be provided in a portion of the bottom near the inflow opening.

  In the flow control valve of the present invention, the valve member has a liquid draining portion that communicates the inside of the housing and the inflow opening at a portion on the seat surface side. For this reason, even when the valve member is seated on the seat surface of the housing when the air pressure on the inflow opening side is below a predetermined value, the interior of the housing communicates with the inflow opening and is a space defined by the housing and the valve member. Fuel will not accumulate. Therefore, problems such as those described above that hinder the operation of the valve member and problems that cause the breather tube to deteriorate can be avoided.

  In the flow control valve of the present invention, the shape of the valve member is formed into a shape having a substantially bottomed cylindrical shape with both ends open and a bottom opening outer edge (hereinafter referred to as a small-diameter convex portion) protruding to the other end side. In addition, when the bottom portion is disposed in the housing for the seated person, there is an advantage that the position of the biasing member can be regulated by the small-diameter convex portion. On the other hand, since the small-diameter convex portion has a shape protruding to the other end side, the opening on the bottom side does not become the lowermost portion in the vertical direction in the cylinder of the valve member. For this reason, a fuel etc. may accumulate in the part by the side of the bottom part inside the cylinder of a valve member. In this case, the valve member may become heavy due to accumulated fuel or the like, and the operation of the valve member may be hindered, for example, the operation of the valve member may vary. Of the bottom of the valve member, a portion near the inflow opening, that is, a portion of the bottom of the valve member that is disposed at the lowest position in the vertical direction in the housing, a second drainage portion that communicates the inside of the cylinder and the inflow opening. By providing, the trouble that fuel etc. accumulate is eliminated.

  Further, when the small-diameter convex portion described above is not provided, when a part of the bottom portion of the valve member protrudes to the other end side, an opening on the bottom portion side is provided in a portion near the inflow opening in the bottom portion. If this is the case, the problem that fuel or the like accumulates inside the cylinder as in the case described above is eliminated.

  The flow control valve of the present invention includes a first valve portion and a second valve portion, similar to the flow control valve shown in FIGS. 7 to 9 described above, and is shown in FIGS. Excellent response to changes in gas pressure with the same mechanism as the flow control valve. For this reason, when the flow control valve of the present invention is used, for example, in a breather circuit of a fuel tank, it is possible to flexibly and reliably cope with high-speed oil supply and low-speed oil supply.

  The flow control valve of the present invention is used, for example, as a flow control valve for a circulation line represented by the above-described breather circuit.

  The housing movably accommodates the valve member, and has a gas inflow opening and an outflow opening. The fixing position of the housing can be variously set according to the purpose of use of the flow control valve. For example, when the flow control valve of the present invention is applied to the breather nipple portion, the housing is airtightly fixed to the upper part of the fuel tank. . In this case, the inflow opening communicates with the gas phase of the fuel tank, and the outflow opening communicates with the breather nipple. At this time, the housing may protrude outside the fuel tank, or can be disposed inside the fuel tank. The method of fixing the housing to the fuel tank is not particularly limited, such as a method of mechanically fixing or a method of fixing by adhesion or welding.

  When the flow control valve of the present invention is applied to the breather nipple portion, it is preferable to provide a cylindrical portion extending into the fuel tank at the lower portion of the housing. In general, the fuel tank is provided with a full tank detection valve, and when the fuel level reaches a predetermined position, the full tank detection valve is operated, and an automatic stop of the fuel gun is activated by an increase in the tank internal pressure. If the inflow opening of the housing is located in the gas phase of the tank when full tank is detected, a vapor leak from the fuel filler port will occur through the breather circuit. Therefore, when the fuel level reaches a predetermined position, the lower end of the housing communicating with the inflow opening needs to be submerged. Therefore, by forming a cylindrical portion extending into the fuel tank and keeping the position of the lower end opening of the cylindrical portion below the liquid level when full, it is possible to prevent vapor leak from the fuel filler opening.

  The cylindrical portion extending into the fuel tank may be integrated with the housing, but it is preferable that a cylindrical member formed separately from the housing is integrated with the housing in an airtight manner. In this way, it is possible to easily cope with various fuel tanks having different full liquid level positions by simply adjusting the length of the cylindrical member. Most of the housing and the breather nipple are made of a plurality of types of fuel. Can be shared in tanks.

  When the flow control valve of the present invention is applied to, for example, a breather nipple portion, the urging force by the urging means should be designed so that the valve member does not lift up due to the gas pressure in the tank during low-speed fueling. Good. Thereby, even if the gas pressure in the tank varies during low-speed refueling, the first valve portion is prevented from closing, and an increase in the amount of adsorption to the canister can be suppressed. If the valve member is designed to be lifted by the gas pressure in the large tank during high-speed fueling, the opening area of the first valve portion gradually decreases as the valve member moves away from the inflow opening. The second valve portion can be configured to open the communication between the inflow opening and the outflow opening at once when the difference between the atmospheric pressure on the side and the atmospheric pressure on the outflow opening side exceeds a predetermined value. Therefore, since the relationship between the gas pressure and the breather gas flow rate is close to a steep S-curve, the flow control valve exhibits excellent responsiveness and can suppress an increase in the amount of adsorption to the vapor leak or the canister.

  In the flow control valve of the present invention, the valve member has a substantially bottomed cylindrical shape, the housing has a convex portion protruding toward the inflow opening, and the first valve portion is formed between the convex portion and the valve member. Is preferred. In this case, the convex portion has a cylindrical shape, and the cylindrical portion of the valve member has a shape corresponding to the inner periphery or the outer peripheral shape of the convex portion, and the convex portion enters one end of the cylindrical portion, or the valve member enters the convex portion. The first valve portion can be gradually closed by entering. Furthermore, in this case, there is an advantage that the moving direction of the valve member can be guided by the convex portion.

  The valve member is extrapolated to the convex part, and the first valve part is constituted by the through hole and the convex part provided on the side wall of the valve member, or the through hole and the valve member provided on the side wall of the convex part. The first valve portion is preferably formed so that the through hole is gradually closed as the valve member moves. If it does in this way, it can prevent that a valve member interferes with a convex part at the beginning of movement, and can move a valve member stably by guidance of a convex part.

  The second valve portion is formed between the flange portion and the housing, and is a portion that opens the communication between the inflow opening and the outflow opening in accordance with movement in the opening direction, that is, in the axial direction. Since the valve member is movably disposed in the housing and the flange portion protrudes in the outer circumferential direction of the valve member, the second valve portion is partitioned by the flange portion into the inflow opening and the outflow opening depending on the position of the valve member. Can be closed, or the partition can be released to open the second valve portion.

  The second valve part is designed to close the communication between the inflow opening and the outflow opening while the first valve part is open, and to open the communication between the inflow opening and the outflow opening at the moment when the valve member starts to move. However, it is preferable to design the valve member so that the second valve portion is opened at the same time as the valve member is moved by a predetermined amount and the first valve portion is closed. When the flow control valve of the present invention is applied to the breather nipple portion of the breather circuit, if the design is made as described above, the pressure in the housing on the downstream side of the valve member becomes atmospheric pressure when the first valve portion is closed. The pressure in the housing upstream of the valve member is the gas pressure in the tank. In this case, since the differential pressure between the pressure on the downstream side and the pressure on the upstream side of the valve member in the housing increases, the valve member moves more quickly, and the relationship between the gas pressure and the breather gas flow rate is Furthermore, it becomes close to a steep S-shaped curve, and the increase in the amount of adsorption to the vapor leak and the canister can be more reliably suppressed.

  In the flow control valve of the present invention, the valve member has a liquid draining portion that communicates the inside of the housing and the inflow opening at a portion on the seating surface side. The liquid draining portion only needs to communicate the inside of the housing with the inflow opening. For example, the drainage portion has various shapes such as a hole shape, a groove shape, and a slit shape provided in the seat surface side portion of the valve member. be able to. By providing a liquid drainage section, a space is provided for fluid to flow even when the valve member is seated on the seat surface of the housing when the air pressure on the inflow opening side is below a predetermined value. Liquid is discharged through this space into the inflow opening. The liquid draining part may be provided only at one place or at a plurality of places, but by providing at a plurality of places, a liquid such as fuel can be discharged more reliably. When providing a liquid drain part in multiple places, it is preferable to disperse | distribute a liquid drain part in the circumferential direction of a valve member. As described above, the valve member may swing and tilt in the housing. However, when the drain holes are provided in the circumferential direction of the valve member, the valve member corresponds to the inclination of the valve member in various directions. The accumulated liquid can be discharged more reliably.

  In the flow control valve of the present invention, an interference flange that protrudes in the outer peripheral direction may be provided at a position closer to the inflow opening than the flange in the valve member. In some cases, the valve member swings and tilts in the housing, but by providing the interference flange, the angle at which the valve member can swing is reduced, and the valve member moves stably. It is preferable that the interference flange protrudes largely so that the space between the outer surface of the valve member and the inner surface of the housing becomes smaller. Furthermore, it is preferable that the interference collar is provided at a position away from the collar. In these cases, the angle at which the valve member can swing becomes smaller, and the inclination angle of the valve member becomes smaller, so that the valve member moves more stably. For this reason, the flow rate control valve is more excellent in responsiveness to changes in gas pressure. In order to move the valve member stably, the interference flange is preferably provided so that the inclination angle of the valve member is within 4 degrees.

  It is preferable that a second through hole that communicates the inside of the housing and the inflow opening is provided in the interference flange. In this case, since the gas flowing in from the inflow opening flows into the housing through the second through hole, a sufficient gas flow path is ensured even when the interference flange is provided. The second through-hole may be provided only at one place of the interference flange, or may be provided at a plurality of places. However, when provided at a plurality of places, there is an advantage that a gas flow path can be secured more reliably. . And when providing a 2nd through-hole in multiple places, it is preferable to distribute and provide a 2nd through-hole in the circumferential direction of an interference collar part. This is because the gas flow path is more reliably secured in response to the inclination of the valve member in various directions.

  The biasing means may be the weight of the valve member itself, or a spring or the like may be used. The biasing force can be variously set according to the purpose.

Hereinafter, the present invention will be described specifically by way of examples.

Example 1
1 to 5 are sectional views schematically showing the flow control valve of the first embodiment, and the flow control valve of the present embodiment will be described with reference to the drawings.

  The flow control valve of the first embodiment is applied to a breather nipple portion of a breather circuit, and is welded and fixed to the upper portion of the fuel tank 100 as shown in FIG. 2, and a breather tube 200 is inserted into the nipple portion 11. Is. The breather tube 200 is connected to the vicinity of the fuel filler opening of the inlet pipe 300.

  As shown in enlarged views in FIGS. 3 to 5, this flow control valve is engaged and fixed to the cover 1 manufactured by two-color molding, the cylindrical member 2 welded and fixed to the cover 1, and the cylindrical member 2. The seat plate 3, the valve member 5, and the spring 6 are configured.

  The cover 1 includes a bottomed cylindrical container 10, a nipple part 11 projecting radially outward from the container part 10, and a ring-shaped weld part 12 formed on the opening peripheral edge of the container part 10. have. The container-like portion 10 and the nipple portion 11 are formed from a modified polyethylene outer layer 13 and a polyamide inner layer 15, and the welded portion 12 is formed from the same modified polyethylene as the outer layer 13.

  The tubular member 2 made of polyamide has a reduced diameter portion 20 with an inner diameter reduced at an intermediate portion, and a flange portion 21 is formed on the outer periphery of the reduced diameter portion 20. The upper part of the cylindrical member 2 is fitted into the container-like part 10 of the cover 1, and the flange part 21 is welded to the inner layer 15 of the container-like part 10, so that the cylindrical member 2 is integrated with the cover 1. . A gas inflow hole 22 passes through the reduced diameter portion 20 of the cylindrical member 2. Further, an opening 23 is provided in the side wall of the cylindrical member 2, and the opening 23 communicates with the inside of the nipple portion 11.

  The seat plate 3 has a disk-shaped base portion 30, a plurality of locking claws 31 arranged at intervals on the peripheral edge portion of the base portion 30, and a recess 32 at the center that protrudes in the axial direction from the center of the base portion 30. Convex part 33, and is formed from polyacetal resin. A locking hole 35 is formed at the tip of the cylindrical member 2, and the seat plate 3 is fixed to the cylindrical member 2 by engaging the locking claw 31 with the locking hole 35. In the flow control valve of the present embodiment, a housing 4 is formed inside the cover 1 by a cylindrical member 2 and a seat plate 3. In the flow control valve of this embodiment, the gas inflow hole 22 corresponds to an inflow opening, and the opening 23 of the cylindrical member 2 communicating with the nipple portion 11 corresponds to an outflow opening. The upper surface of the reduced diameter portion 20 serves as a seat surface on which the valve member 5 is seated when the pressure on the inlet opening side (gas inlet 22) is equal to or lower than a predetermined value.

  The valve member 5 is provided with a bottomed cylindrical tube portion 50, a flange portion 51 provided in an intermediate portion in the axial direction of the tube portion 50, and a position below the flange portion 51, that is, a position on the inflow opening side. The interference flange 52 is formed. The flange 51 and the interference flange 52 protrude from the outer edge of the valve member 5 in the outer circumferential direction. The interference flange 52 is provided with second through holes 53 in the form of through holes at a plurality of locations in the circumferential direction. Furthermore, a cylindrical small-diameter convex portion 55 that protrudes toward the other end side of the valve member 5, that is, the inner side of the cylindrical portion 50, is formed on the bottom portion of the cylindrical portion 50 (the bottom portion of the cylindrical portion 5). The inside of the cylinder 55 is a vent hole 56 that communicates the inside and outside of the cylinder.

  The outer diameter of the cylindrical portion 50 is larger than the inner diameter of the reduced diameter portion 20 of the cylindrical member 2, and the valve member 5 moves up and down in the housing 4 in a state where the downward movement is restricted by the reduced diameter portion 20. It is free. Further, the outer diameters of the flange 51 and the interference flange 52 are slightly smaller than the inner diameter of the housing 4 so that the valve member 5 can move smoothly. Further, the inner diameter of the cylindrical portion 50 of the valve member 5 is larger than the outer diameter of the convex portion 33, and the valve member 5 is guided by the convex portion 33 and is movable in the vertical direction. A plurality of through-holes 57 are formed in the distal end side wall of the cylinder portion 50 so as to penetrate the inside and outside of the cylinder portion 50 in the radial direction at intervals in the circumferential direction. The valve member 5 is formed from polyacetal resin. In addition, slit-like drainage portions 58 are provided radially at four locations in the circumferential direction of the cylindrical portion 50 at the reduced diameter portion 20 side portion of the cylindrical portion 50, that is, at the bottom portion side portion of the cylindrical portion 50. ing. The liquid drain part 58 communicates the inside of the housing 4 with the gas inlet 22. In addition, a second liquid draining portion 59 that communicates the inside of the cylinder portion 50 and the gas inlet 22 is provided in a portion on the bottom side of the cylinder portion 50.

  The spring 6 is interposed between the small-diameter convex portion 55 and the convex portion 33, and the valve member 5 is biased in the direction toward the gas inflow hole 22.

  According to the flow control valve of the present embodiment, during low-speed refueling, the outer peripheral surfaces of the flange 51 and the interference flange 52 are below the opening 23 communicating with the nipple portion 11 as shown in FIG. Facing close to the surface. The gas in the fuel tank 100 mainly passes from the lower end of the cylindrical member 2 through the gas inflow hole 22, the vent hole 56 or the second liquid drain part 59, and the through hole 57, and the breather gas passes from the nipple part 11 to the breather tube 200, The inlet pipe 300 is circulated. At this time, even if the gas pressure in the fuel tank 100 acts on the valve member 5, the sum of the urging force of the spring 6 and the weight of the valve member 5 is larger than the force received from the gas pressure. do not do. In this state shown in FIG. 3, the tip of the convex portion 33 is located above the upper end of the through hole 57, and the flow of the gas flowing through the through hole 57 is not hindered, and the breather circuit functions stably.

  During high-speed refueling, the gas pressure in the fuel tank 100 increases, and the pressure acts on the valve member 5, so that the valve member 5 starts moving in the direction approaching the convex portion 33. Then, the tip of the convex portion 33 wraps with the through hole 57, and the opening area of the through hole 57 gradually narrows as the valve member 5 rises as shown in FIG. That is, the gap 70 between the through hole 57 and the convex portion 33 acts as the first valve portion, and the first valve portion is gradually closed. At the same time, the collar 51 rises, but the collar 51 does not appear in the opening 23 during the initial period.

  When the valve member 5 further moves in the direction closer to the convex portion 33 as the gas pressure in the fuel tank 100 increases, the opening area of the through hole 57 is further narrowed, and finally the through hole 57 is closed by the convex portion 33. . At this time, the gas pressure on the lower side (tank side) from the flange part 51 rapidly increases, and the difference from the atmospheric pressure on the upper side (fuel supply port side) from the flange part 51 increases rapidly. Then, the valve member 5 rises at a stretch, and as shown in FIG. 5, the flange portion 51 is disposed above the opening 23, and the opening 23 that is a gas outflow hole and the gas inflow hole 22 communicate with each other. That is, the gap 71 between the flange portion 51 and the housing 4 acts as the second valve portion, and the second valve portion is fully opened. At this time, the gas flowing into the housing 4 from the gas inflow hole 22 reaches the opening 23 via the second through hole 53 of the interference flange 52.

  Then, at the time of low-speed refueling or when refueling is stopped, the valve member 3 quickly moves by the urging force of the spring 6 and returns to the state of FIG.

  According to the flow control valve of the present embodiment, as described above, the second valve portion opens the communication between the inflow opening and the outflow opening at a stretch, so that the relationship between the gas pressure and the breather gas flow rate has a steep S curve. Close to. For this reason, the flow control valve of the present embodiment is excellent in responsiveness to changes in gas pressure, and can suppress excess gas from flowing into the canister or vapor leak.

  Furthermore, a liquid draining portion 58 is provided in the flow control valve of this embodiment. For this reason, as shown in FIG. 3, even when the valve member 5 is seated on the seat surface formed from the upper surface of the reduced diameter portion 20, the fuel accumulated in the housing 4 passes through the liquid draining portion 58 and the gas inlet 22. And discharged to the fuel tank 100. For this reason, fuel does not accumulate in the space defined by the housing 4 and the valve member 5, the valve member 5 is fixed to the housing 4, and the operation of the valve member 5 is hindered, or the breather is deteriorated due to deterioration of the fuel. The deterioration of the tube is avoided. Further, since the second liquid draining portion 59 is provided, the fuel does not accumulate at the bottom of the cylindrical portion 50 and the valve member 5 operates stably.

  In the flow control valve of the present embodiment, the interference flange 52 is provided at a position closer to the inflow opening than the flange 51, so that a large gas pressure acts on the valve member 5 partially. When 5 swings, the inclination of the valve member 5 stops at a position where the cylindrical portion 50 and the convex portion 33 are in contact with each other and the interference flange portion 52 and the cylindrical member 2 are in contact with each other. The interference flange 52 suppresses the valve member 5 from being greatly inclined, and the movement of the valve member 5 is more stable. Therefore, the flow control valve of the present embodiment is further excellent in responsiveness to changes in gas pressure. It will be a thing.

  In this embodiment, a small-diameter convex portion 55 is provided at the bottom of the cylindrical portion 50, and a vent hole 56 is formed from the inside of the cylindrical portion of the small-diameter convex portion 55. For example, as shown in FIG. In the case where the bottom portion of 50 is simply projected, the vent hole 56 may be provided in a portion near the inflow opening (gas inlet 22) in the bottom portion. In this case, the vent hole 56 constitutes a part of the gas flow path and functions as a discharge port for discharging the liquid from the bottom portion of the tubular portion 50 of the valve member 5 in the same manner as the second liquid draining portion 59 described above. Also have.

It is sectional drawing of the flow control valve | bulb of Example 1 of this invention. It is explanatory drawing of the breather circuit provided with the flow control valve of Example 1 of this invention. It is explanatory drawing which shows the action | operation of the flow control valve of Example 1 of this invention. It is explanatory drawing which shows the action | operation of the flow control valve of Example 1 of this invention. It is explanatory drawing which shows the action | operation of the flow control valve of Example 1 of this invention. It is sectional drawing which shows the other example of a valve member among the flow control valves of this invention. It is explanatory drawing which shows the action | operation of the conventional flow control valve. It is explanatory drawing which shows the action | operation of the conventional flow control valve. It is explanatory drawing which shows the action | operation of the conventional flow control valve.

Explanation of symbols

1: Cover 2: Cylinder member 4: Housing 5: Valve member 51: Gutter part 52: Interference gutter part 58: Liquid drainage part 59: Second liquid drainage part

Claims (3)

A housing having an inflow opening through which the fluid flows in and an outflow opening through which the fluid flowing in from the inflow opening flows out to the outside; a valve member having a flange projecting in the outer circumferential direction and movably disposed in the housing; Biasing means for biasing the valve member in a direction close to the inflow opening,
A first valve portion formed between the valve member and the housing and gradually closing the communication between the inflow opening and the outflow opening as the valve member moves in a direction away from the inflow opening; A second valve portion that is formed between the portion and the housing and opens the communication between the inflow opening and the outflow opening in accordance with the movement of the valve member in a direction away from the inflow opening.
When the pressure on the inflow opening side is below a predetermined value, the first valve portion is open and the second valve portion is closed, and the pressure difference between the inflow opening side and the outflow opening exceeds a predetermined value A flow control valve for a circulation line, wherein the second valve portion is configured to open the communication between the inflow opening and the outflow opening at once,
The housing has a seat surface on which the valve member is seated when the pressure on the inflow opening side is a predetermined value or less,
The flow rate control valve according to claim 1, wherein the valve member has a liquid drainage portion communicating with the inside of the housing and the inflow opening at a portion on the seat surface side.   The valve member has a substantially bottomed cylindrical shape with both ends opened, and an opening outer edge on the bottom side protrudes toward the other end side, and is disposed in the housing with the bottom facing the seating surface. The flow rate control valve according to claim 1, wherein a portion near the opening has a second drainage portion that communicates the inside of the cylinder and the inflow opening. The valve member has a substantially bottomed cylindrical shape with both ends open, and a part of the bottom protrudes toward the other end, and is disposed in the housing with the bottom facing the seat surface. The opening on the bottom is the bottom The flow rate control valve according to claim 1, wherein the flow rate control valve is provided near the inflow opening.

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