JP4379719B2 - Flow control valve - Google Patents

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.

  By the way, when refueling the fuel tank of an automobile, if a lot of new air is caught from the refueling port, vaporization of the fuel is promoted in the fuel tank, so that the amount of gas flowing to the canister increases and the amount of adsorption of the canister increases. There was a problem that. Therefore, a breather tube is provided to communicate the gas phase portion in the fuel tank and the outside air. 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 into a breather nipple fixed so as to communicate with the gas phase of the fuel tank. Therefore, the vaporized fuel existing 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 the entrainment of new air is reduced and the vaporization of the fuel is suppressed. Therefore, the adsorption amount of the canister can be reduced.

  Further, an orifice is formed inside 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 caught 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.

  However, depending on the specifications and usage of the lubrication gun, there are two types of lubrication speeds during refueling: low speed (typical value: 15 L / min) and high speed (typical value: 38 L / min). Since there are many, the amount of breather gas which circulates through a breather circuit is needed at the time of high-speed oil supply. Therefore, if the opening of the orifice of the breather nipple is enlarged, the amount of breather gas circulating in the breather circuit increases even during low-speed fueling, and vapor leaks from the fuel filler port.

  FIG. 6 shows a conceptual diagram of these relationships. Actually, there are two stages of low-speed oil supply and high-speed oil supply, but FIG. 6 shows that the oil supply speed continuously increases and decreases. The air entrainment amount changes continuously according to the oil supply speed (straight line A). In the case of an orifice with a small opening diameter corresponding to low-speed oil supply, the breather gas flow rate corresponds to the air entrainment amount at low-speed oil supply, but the difference between the air entrainment amount and the breather gas flow rate increases as the oil supply speed increases. Thus, the entrainment of new air promotes the vaporization of fuel in the tank, and the amount of adsorption of the canister increases (curve B). On the other hand, in the case of an orifice having a large opening diameter corresponding to high-speed oil supply, the breather gas flow rate exceeds the air entrainment amount in a range where the oil supply speed is low, and vapor leak occurs (curve C).

  That is, only the conventional breather nipple having only one orifice 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. For this reason, Japanese Patent Application Laid-Open No. 08-216707 proposes a fuel evaporative emission prevention device in which a breather circuit is provided with a variable means for adjusting the amount of fuel evaporative gas circulation according to the pressure. Japanese Patent Laid-Open No. 2003-0208010 proposes that a breather circuit is provided with a connector with a built-in valve that adjusts the fuel evaporative gas circulation rate in accordance with the pressure.

  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 will be described with reference to FIG.

  Since the pressure of the circulating gas is greatly affected by the temperature, there are variations at low speed or high speed. Accordingly, assuming that the flow rate of the breather gas to be secured at the time of low-speed refueling is (b) and the flow rate of breather gas to be secured at the time of high-speed refueling is (b), the relationship between the ideal gas pressure and gas flow rate is as shown by curve D. . During low-speed refueling, the pressure of the circulating gas has a width of (a) to (b), and during high-speed refueling, the pressure of the breather gas has a width of (c) to (d).

  However, the conventional valve has a structure in which the valve opens as the gas pressure increases, and the breather gas flow rate gradually increases. For this reason, for example, when the valve is adjusted so that the valve opens at the highest gas pressure (b) assumed at the time of low-speed refueling so that vapor leak from the fuel filler port does not occur, the relationship between the gas pressure and the breather gas flow rate is as shown by curve E become. Therefore, when the gas pressure varies slightly during high-speed refueling as indicated by point X, the breather gas flow rate is insufficient and the amount of gas flowing to the canister increases.

  On the other hand, when adjusting so that a predetermined breather gas flow rate is almost secured at the lowest gas pressure (c) assumed at the time of high-speed refueling, the relationship between the gas pressure and the breather gas flow rate becomes a curve F, as shown by the Y point. If the gas pressure varies at a high speed during low-speed refueling, the breather gas flow rate becomes excessive and vapor leak occurs.

  In the prior art, since the variable means for adjusting the fuel evaporative gas circulation amount according to the pressure is provided in the middle of the breather circuit, the number of parts increases and there is a problem in space. In addition, the proposal described in the above publication has a problem in that since the ventilation resistance is further generated in the breather circuit, the control becomes unstable and difficult to manage compared to the case where the tank internal pressure itself is used.

Furthermore, in a connector with a built-in valve as described in Japanese Patent Application Laid-Open No. 2003-028010, the gas flow path in the connector is linear and the valve is built in, so the total length of the connector is relatively long. On the other hand, it is required that the breather tube be arranged along the inlet pipe as much as possible to reduce the arrangement space, and the length of the breather tube at the portion protruding from the outer peripheral surface of the inlet pipe in the direction orthogonal to the axial direction is It has been shortened as much as possible. Therefore, when the connector with a built-in valve is arranged in the breather circuit, it is difficult to arrange the connector at the connecting portion between the breather tube and the inlet pipe, and it must be arranged in the middle of the breather tube. However, even in this case, it is necessary to bend the pipe that protrudes from the side wall of the inlet pipe and is coupled to the connector into an L shape, which is disadvantageous in terms of cost. That is, in the connector with a built-in valve as described in Japanese Patent Application Laid-Open No. 2003-028010, there is a problem that the arrangement position is restricted and the degree of freedom in design is low.
JP 08-216707 JP2003-0208010

  The present invention has been made in view of the above-described circumstances, and an object to be solved is to be able to accurately cope with an increase / decrease in the necessary breather gas flow rate due to an increase / decrease in the oil supply speed.

The flow control valve of the present invention that solves the above problem has 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, and has a convex portion that protrudes toward the inflow opening. A flow rate control valve comprising a housing, a valve member that has a substantially bottomed cylindrical shape that opens upward, and is movably disposed in the housing, and a biasing means that biases the valve member in a direction close to the inflow opening. Because
A first valve portion which is formed between the convex portion and the valve member and gradually closes 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 valve member and the housing and opens the communication between the inflow opening and the outflow opening as the valve member moves in a direction away from the inflow opening,
When the fluid 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 when the pressure difference between the inflow opening side and the outflow opening side exceeds a predetermined value, This is because the two valve portions are configured to open the communication between the inflow opening and the outflow opening at a stretch.

It is desirable that the valve member is extrapolated to the convex portion, and the first valve portion is formed by the opening and the convex portion of the valve member side wall. Further, the valve member may have a flange portion, and the second valve portion may be formed between the flange portion and the housing.

  The housing has a seating surface on which the valve member is seated when the fluid pressure on the inflow opening side is equal to or lower than a predetermined value. At least one of the housing and the valve member is engaged with the other so as to be between the seating surface and the valve member. It is desirable to have an engaging portion that forms a gap.

  Moreover, it is preferable to apply to the flow control valve used for the breather circuit of a fuel tank. In this case, the housing can be hermetically fixed to the upper part of the fuel tank, the inflow opening can communicate with the gas phase of the fuel tank, and the outflow opening can communicate with the breather nipple. In this case, it is desirable that a cylindrical portion communicating with the inflow opening is formed in the lower portion of the housing.

  According to the flow control valve of the present invention, when the fluid pressure on the inflow opening side is equal to or lower than the predetermined value, the first valve portion is in the open state, so that the fluid flows from the inflow opening to the outflow opening through the first valve portion. When the fluid pressure on the inflow opening side exceeds a predetermined value, the valve member moves and the first valve portion closes. At this time, since the differential pressure between the pressure on the inflow opening side and the pressure in the housing on the outflow opening side suddenly increases, the valve member moves in a direction away from the inflow opening and the second valve portion opens at a stretch. The fluid inside flows out at once from the outflow opening. Therefore, the flow control valve of the present invention is excellent in responsiveness, and when used in a fuel tank breather circuit, can flexibly cope with high-speed and low-speed oil supply.

  The housing has a seating surface on which the valve member is seated when the fluid pressure on the inflow opening side is equal to or lower than a predetermined value. At least one of the housing and the valve member is engaged with the other to connect the seating surface and the valve member. If the structure has an engaging portion that forms a gap therebetween, the valve member can be prevented from adhering to the seat surface, and the operation reliability is improved. Also, liquid fuel or the like that has flowed into the housing can be discharged from the gap through the inflow opening.

  Also, if a cylindrical part communicating with the inflow opening is formed in the lower part of the housing, it is possible to easily cope with various fuel tanks with different full liquid level positions by simply adjusting the length of the cylindrical part. Can do.

  Furthermore, the flow control valve of the present invention can be easily designed so that the central axis of the inflow opening and the central axis of the outflow opening intersect each other. Therefore, since it can be made the full length which allows the movement of a valve member, it can be made very compact. For this reason, even if the breather tube and the inlet pipe are connected to each other, the breather tube can be disposed close to the inlet pipe, and the degree of freedom in designing the breather circuit is greatly improved.

  When the flow control valve according to claim 1 is used in a breather circuit of a fuel tank, when the gas pressure on the inflow opening side is below a predetermined value, the first valve portion is open and the second valve portion is closed. Since it is in a state, the gas flowing into the housing from the inflow opening flows out from the outflow opening through the first valve portion. When the fluid pressure on the inflow opening side exceeds a predetermined value, the valve member moves in a direction away from the inflow opening, and accordingly, the opening area of the first valve portion is reduced, so that the flow velocity is increased. For example, when the valve member has a flange portion and the second valve portion is formed between the flange portion and the housing, the pressure at the upper portion of the flange portion in the housing decreases. At this time, the difference between the pressure at the upper portion of the flange in the housing and the pressure at the inflow opening side suddenly increases rapidly.

  In the case of a flow control valve of a breather circuit, the outflow opening side is almost atmospheric pressure. Therefore, when the difference between the gas pressure on the inflow opening side and the gas pressure on the outflow opening side exceeds a predetermined value during high-speed refueling, the second valve portion opens the communication between the inflow opening and the outflow opening at once, and the gas on the inflow opening side Since the gas quickly flows out from the outflow opening through the two valve portions, the gas pressure in the fuel tank is released at once, and stable oil supply becomes possible.

  For example, in the flow control valve provided in the breather circuit, when there is a large variation between the gas pressure during low-speed lubrication and the gas pressure during high-speed lubrication, the interval between the gas pressure (b) and the gas pressure (c) in FIG. Becomes narrower. Then, in the conventional flow control valve in which the breather gas flow rate gradually increases as the gas pressure increases, the breather gas flow rate tends to be excessive or insufficient, and the amount of gas flowing to the canister tends to increase or vapor leak tends to occur. However, in the flow control valve of the present invention, even if the interval between the gas pressure (b) and the gas pressure (c) is narrow, the breather gas flow rate increases at a stretch between the gas pressure (b) and the gas pressure (c). The drawn curve is close to the ideal curve (D).

  As the fluid, both liquid and gas can be used.

  The fixing position of the housing can be variously set according to the purpose. For example, when applied to the breather nipple portion, the housing is airtightly fixed to the upper portion 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. The housing may protrude outside the fuel tank, or can be arranged inside the fuel tank. In order to fix the housing to the fuel tank, there is no particular limitation such as a method of mechanically fixing or a method of fixing by adhesion or welding.

  When applied to the breather nipple portion, it is preferable that the lower portion of the housing has a cylindrical portion extending into the fuel tank. The fuel tank is provided with a full tank detection valve. When the fuel level reaches a predetermined position, the full tank detection valve is actuated, and an automatic stop of the fuel gun is activated by an increase in the tank internal pressure. If the lower end of the cylindrical portion is located in the gas phase of the tank when full tank is detected, vapor leak from the fuel filler port will occur through the breather circuit. Accordingly, by setting the position of the lower end opening of the cylindrical portion below the liquid level position when the tank is full, vapor leak from the fuel filler port can be prevented.

  Although the cylindrical portion extending into the fuel tank may be formed integrally with the housing, 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.

  The flow control valve of the present invention includes a valve member movable in a housing and a biasing means for biasing the valve member in a direction close to the inflow opening, and is formed between the valve member and the housing. The first valve portion that gradually closes the communication between the inflow opening and the outflow opening in accordance with the movement of the valve member in the direction of moving away, and the movement of the valve member in the direction of moving away from the inflow opening formed between the valve member and the housing. A second valve portion that opens the communication between the inflow opening and the outflow opening is provided.

  In this flow control valve, when the fluid pressure on the inflow opening side is smaller than the urging force of the urging means and the valve member is close to the inflow opening, the first valve portion is open. It flows out from the outflow opening through one valve part. As the valve member moves in a direction away from the inflow opening due to the increase in fluid pressure on the inflow opening side, the opening area of the first valve portion gradually decreases, so the fluid pressure on the inflow opening side increases more and more. When the difference between the fluid pressure and the fluid pressure on the outflow opening side exceeds a predetermined value, the second valve portion opens the communication between the inflow opening and the outflow opening at once.

  For example, in the case of a flow rate control valve applied to the breather nipple portion, the urging force by the urging means is designed to be an urging force that does not lift the valve member due to the gas pressure in the tank during low-speed fueling. As a result, 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 a large tank gas pressure during high-speed fueling, the opening area of the first valve portion gradually decreases as the valve member moves away from the inflow opening. When the difference between the fluid pressure and the fluid pressure on the outlet opening side exceeds a predetermined value, the second valve portion can be configured to open the communication between the inlet opening and the outlet opening at once. Therefore, the relationship between the gas pressure and the breather gas flow rate is close to the ideal curve (D) in FIG. 7, and an increase in the amount of adsorption to the vapor leak and the canister can be suppressed.

The valve member has a substantially bottomed cylindrical shape, and the housing has a convex portion protruding toward the inflow opening . The convex portion is cylindrical, and the cylindrical portion of the valve member has a shape corresponding to the inner or outer peripheral shape of the convex portion, and the convex portion enters one end of the cylindrical portion, or the valve member enters the inside of the convex portion. By doing so, the first valve portion is gradually closed and a pressure difference is generated between the inflow opening side and the outflow opening side, so that the valve member can be moved more quickly.

The valve member is extrapolated to the convex part, and the first valve part is formed by the opening part and convex part of the valve member side wall . By doing in this way, it can prevent that a valve member interferes with a convex part in the movement initial stage, and can move a valve member stably by guidance of a convex part. In this case, the first valve portion may be formed by forming a through hole in the side peripheral surface of the valve member or the convex portion and gradually closing the through hole as the valve member moves. it can.

  The second valve portion is formed between the valve member and the housing, and opens the communication between the inflow opening and the outflow opening as the valve member moves in a direction away from the inflow opening. Forming the second valve portion between the valve member and the housing by forming a flange portion that partitions the inflow opening and the outflow opening, and by configuring the flange portion to release the partition when the valve member moves. Can do. While the first valve portion is open, the second valve portion may be designed so that the communication between the inflow opening and the outflow opening is closed and the second valve portion is opened at the moment when the valve member starts to move. It is preferable to design the valve member so that the second valve portion opens at the same time that the valve member moves by a predetermined amount and the first valve portion closes. Further, since the pressure receiving area is increased by providing the collar portion, there is an effect that the valve member is more easily moved.

  In the case of the flow control valve applied to the breather nipple portion of the breather circuit, when the first valve portion is closed, the pressure in the housing on the downstream side of the valve member becomes atmospheric pressure when the first valve portion is closed. Since the pressure in the housing on the upstream side becomes the tank internal pressure, the differential pressure increases and the valve member moves more rapidly. Accordingly, even if the gas pressure at the time of low-speed oil supply and the gas pressure at the time of high-speed oil supply vary widely and the gap between the gas pressure (b) and gas pressure (c) in FIG. Therefore, the increase in the amount of adsorption to the canister can be suppressed, so that it is possible to accurately cope with the increase / decrease in the breather gas flow rate due to the increase / decrease in the oil supply speed, and to secure the necessary breather gas flow rate.

  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.

  By the way, in the case of the flow control valve provided in the breather circuit, liquid fuel may enter the housing. In such a case, when the valve member has a seat surface on which the gas pressure on the inflow opening side is below a predetermined value, the valve member is fixed to the seat surface via liquid fuel, and the operation becomes unstable. There is a fear.

  Therefore, in such a case, it is preferable to form an engaging portion that engages with the other of at least one of the housing and the valve member to form a gap between the seating surface and the valve member. In this way, since the liquid fuel that has flowed into the housing can be discharged from the gap, the valve member can be prevented from adhering to the seat surface, and the operation reliability can be improved. Examples of the engaging portion include a protrusion, a stepped portion, a groove, and an uneven surface.

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

Example 1
FIG. 1 shows a cross-sectional view of the flow control valve of this embodiment. As shown in FIG. 2, the flow control valve is welded and fixed to the upper portion of the fuel tank 100, and the breather tube 200 is inserted into the nipple portion 11. The breather tube 200 is connected to the vicinity of the filler opening of the inlet pipe 300.

  The flow control valve of the present embodiment includes a cover 1 manufactured by two-color molding, a cylindrical member 2 welded and fixed to the cover 1, a valve member 3, and a spring 5.

  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 13 formed on the opening peripheral edge of the container part 10. The container-like portion 10 and the nipple portion 11 are formed of an outer layer 14 made of modified polyethylene and an inner layer 15 made of polyamide, and the welded portion 13 is made of the same modified polyethylene as the outer layer 14. Further, from the center of the upper bottom portion of the container-like portion 10, a cylindrical convex portion 16 having a conical portion at the tip is formed so as to protrude in the axial direction of the cylindrical member 2.

  The cylindrical member 2 includes a bottomed cylindrical first cylindrical portion 20, a second cylindrical portion 21 that extends coaxially from the first cylindrical portion 20 and has a smaller diameter than the first cylindrical portion 20, a first cylindrical portion 20, and a first cylindrical portion 20. The flange portion 22 is formed at the boundary portion of the two cylinder portions 21 and protrudes outward in the radial direction, and is entirely formed of polyamide. The first tubular portion 20 is fitted into the container-like portion 10 of the cover 1 and the flange portion 22 is welded to the inner layer 15 of the container-like portion 10, so that the tubular member 2 is integrated with the cover 1. As a result, the housing 4 is formed between the first cylindrical portion 20 and the container-like portion 10. A gas inflow hole 23 passes through the bottom of the first cylinder portion 20 of the cylinder member 2, and the housing 4 communicates with the gas phase in the fuel tank 100 through the second cylinder portion 21 and the gas inflow hole 23. The housing 4, the convex portion 16 projecting from the container-like portion 10, the gas inflow hole 23, and the second cylindrical portion 21 are located on the same axis.

  The valve member 3 is composed of a bottomed cylindrical tube portion 30 and a flange portion 31 protruding radially outward from the outer peripheral surface of the tube portion 30 as shown in FIGS. It is formed from resin. A through hole 32 having a diameter smaller than that of the gas inflow hole 23 is formed at the center of the bottom of the cylindrical portion 30. The outer diameter of the collar portion 31 is slightly smaller than the inner diameter of the housing 4, and the inner diameter of the cylindrical portion 30 is slightly larger than the outer diameter of the convex portion 16, so that the valve member 3 can move in the housing 4 in the axial direction. ing.

  A spring 5 is interposed between the upper bottom portion of the housing 4 and the flange portion 31, and the spring 5 biases the valve member 3 toward the lower bottom portion of the housing 4 with a very weak force. In this state, as shown in FIG. 3, a gap 40 is formed between the opening end face of the cylindrical portion 30 and the convex portion 16, and the outer peripheral surface of the flange portion 31 is below the opening of the nipple portion 11 and the inner periphery of the housing 4. Facing close to the surface. The convex portion 16, the cylindrical portion 30, the through hole 32, and the gas inflow hole 23 are located on the same axis.

  In the flow control valve of this embodiment, the welded portion 13 of the cover 1 is welded and fixed to the peripheral edge of the opening 101 so that the cover 1 covers the opening 101 formed on the upper surface of the fuel tank 100, and The second cylinder part 21 is located in the gas phase of the fuel tank 100. The gas inflow hole 23 corresponds to the inflow opening, and the opening of the housing 4 closest to the nipple portion 11 corresponds to the outflow opening.

  According to the flow control valve of this embodiment, during low-speed refueling, the gas in the fuel tank 100 passes from the second cylinder portion 21 through the gas inflow hole 23, the through hole 32, and the gap 40, and the breather gas passes from the nipple portion 11 to the breather. Circulate the tube 200 and the inlet pipe 300. At this time, the gas pressure in the fuel tank 100 acting on the valve member 3 acts on the peripheral surface of the through hole 32 exposed to the gas inflow hole 23, but the urging force of the spring 5 and the weight of the valve member 3 Is larger than the force received from the gas pressure, the valve member 3 does not move. The opening area of the gap 40 at this time corresponds to φ3 (7 mm 2) in terms of the total channel cross-sectional area.

  During high-speed refueling, the gas pressure in the fuel tank 100 rises, and the pressure acts on the valve member 3, so that the valve member 3 starts moving in the direction close to the convex portion 16. Then, a gap 33 is formed between the lower bottom portion of the cylindrical portion 30 and the bottom portion of the first cylindrical portion 20, and the gas pressure in the tank acts on the flange portion 31, so that the valve member 3 is further pushed up. When the valve member 3 moves in this manner, the opening area of the gap 40 is reduced as shown in FIG. Then, since the upper side (fuel supply port side) of the valve member 3 from the flange 31 is atmospheric pressure, the pressure difference from the lower side (tank inside) of the flange 31 increases rapidly. As a result, as shown in FIG. 5, the valve member 3 rises at once, and the opening area of the gap 41 increases at a stretch and opens. In addition, the opening area of the gap 41 corresponds to the maximum channel cross-sectional area of φ5 (19 mm 2) (the channel cross-sectional area of the nipple portion 11). That is, in this embodiment, the gap 40 constitutes the first valve part, and the gap 41 constitutes the second valve part.

  When the low-speed refueling or when the refueling is stopped, the valve member 3 is quickly moved by the urging force of the spring 5 and returns to the state shown in FIG.

  That is, according to the flow rate control valve of the present embodiment, the relationship between the gas pressure and the breather gas flow rate is as shown by the ideal curve D in FIG. 7, so that the followability with respect to the increase and decrease in the fueling speed is excellent, and the breather gas flow rate increases and decreases instantaneously. . Therefore, it is possible to suppress an excess gas from flowing into the canister or a vapor leak. The adjustment is easier than in the case of using two members of the conventional orifice and valve, and the structure is simple, so that the cost is low. Furthermore, since the cylindrical member 2 is configured as a separate member from the cover 1, only the cylindrical member 2 needs to be changed when the length of the second cylindrical portion 21 is adjusted in accordance with the shape and volume of the fuel tank 100. And the valve member 3 can be shared.

  Although depending on the circulation amount of the breather gas, the opening area of the gap 40 (first valve portion) may be gradually decreased and the opening area of the gap 41 (second valve portion) may be gradually increased. .

(Example 2)
In the above embodiment, the valve member 3 is seated on the peripheral edge of the gas inflow hole 23 during low-speed refueling. Therefore, when liquid fuel enters the housing 4, the liquid fuel enters the interface between the valve member 3 and the peripheral edge of the gas inflow hole 23, and the valve member 3 is fixed due to the liquid tension, resulting in an operation failure. It may become stable.

  Therefore, in the present embodiment, as shown in FIG. 8, a plurality of protrusions 24 are formed on the peripheral edge of the gas inflow hole 23 so as to protrude upwardly at intervals in the circumferential direction. By doing so, the valve member 3 is seated on the top of the protrusion 24 and the contact area is reduced, so that the valve member 3 is prevented from sticking and the operation stability is improved.

  The protrusion 24 may be formed on the bottom surface of the valve member 3, or a groove, a texture pattern or the like may be formed on at least one of the peripheral edge of the gas inflow hole 23 or the bottom of the valve member 3 instead of the protrusion 24. Similar effects are achieved.

(Example 3)
As shown in FIG. 9, a plurality of ribs 26 spaced apart in the circumferential direction are formed on the inner peripheral surface of the housing 4 as means for preventing the valve member 3 from sticking in the same manner as in the second embodiment. By engaging with the rib 26, further lowering of the valve member 3 can be restricted.

(Example 4)
The flow control valve of the present embodiment shown in FIGS. 10 to 12 is the same as that of the first embodiment except that the structure of the valve member 3, the cylindrical member 7, and the convex portion 16 in the first embodiment is changed.

  This flow control valve includes a cover 6 manufactured by two-color molding, a cylindrical member 7 welded and fixed to the cover 6, a valve member 8, a seat plate 9, and a spring 5.

  The cover 6 has a bottomed cylindrical container-like part 60, a nipple part 61 projecting radially outward from the container-like part 60, and a ring-like welded part 62 formed on the opening peripheral edge of the container-like part 60. The container-like portion 60 and the nipple portion 61 are formed of a modified polyethylene outer layer 63 and a polyamide inner layer 64, and the welded portion 62 is formed of the same modified polyethylene as the outer layer 63.

  The tube member 7 made of polyamide has a reduced diameter portion 70 whose inner diameter is reduced at an intermediate portion, and a flange portion 71 is formed on the outer periphery of the reduced diameter portion 70. The upper portion is fitted into the container-like portion 60 of the cover 6, and the flange portion 71 is welded to the inner layer 64 of the container-like portion 60, so that the cylindrical member 7 is integrated with the cover 6. As a result, the housing 4 is formed inside the cover 6. A gas inflow hole 72 passes through the reduced diameter portion 70 of the cylindrical member 7. In addition, a plurality of protrusions 73 are formed on the reduced diameter portion 70 so as to protrude toward the housing 4 at intervals in the circumferential direction.

  The valve member 8 includes a bottomed cylindrical tubular portion 80 and a flange portion 81 that protrudes radially outward from the outer peripheral surface of the intermediate portion of the tubular portion 80, and is formed of polyacetal resin. A convex portion 82 that protrudes inward is formed at the bottom of the cylindrical portion 80, and a vent hole 83 that penetrates in the axial direction is formed in the convex portion 82. The outer diameter of the flange 81 is slightly smaller than the inner diameter of the housing 4, the outer diameter of the cylinder 80 is larger than the diameter of the gas inflow hole 72, and the valve member 8 is restricted from moving downward by the reduced diameter portion 70. In this state, the inside of the housing 4 is movable up and down. In addition, a plurality of through holes 84 that penetrate the inside and outside of the cylinder portion 80 in the radial direction are formed in the distal end side wall of the cylinder portion 80 at intervals in the circumferential direction.

  The seat plate 9 has a disk-shaped base 90, a plurality of locking claws 91 arranged at intervals around the periphery of the base 90, and a recess 93 at the center that protrudes in the axial direction from the center of the base 90. And a convex portion 92, which is made of polyacetal resin. A locking hole 73 is formed at the tip of the cylindrical member 7, and the seat plate 9 is fixed to the cylindrical member 7 by engaging the locking claw 91 with the locking hole 73. The outer diameter of the convex portion 92 is smaller than the inner diameter of the cylindrical portion 80 of the valve member 8, and the valve member 8 is guided by the convex portion 92 and is movable in the vertical direction.

  The spring 5 is interposed between the convex portion 82 and the convex portion 92, and the valve member 8 is urged in a direction toward the gas inlet 72. In this state, as shown in FIG. 11, the outer peripheral surface of the collar portion 81 is opposed to the inner peripheral surface of the housing 4 below the opening of the nipple portion 61.

  As in the first embodiment, the flow control valve of the present embodiment is welded to the peripheral edge of the opening 101 so that the cover 6 covers the opening 101 formed on the upper surface of the fuel tank 100. It is fixed and the lower end of the cylinder member 7 is located in the gas phase of the fuel tank 100. The gas inflow hole 72 corresponds to the inflow opening, and the opening of the housing 4 closest to the nipple portion 61 corresponds to the outflow opening.

  According to the flow control valve of the present embodiment, during low-speed refueling, the gas in the fuel tank 100 passes from the lower end of the cylindrical member 7 through the gas inflow hole 72, the vent hole 83, and the through hole 84, and the breather gas passes from the nipple portion 61. Circulates breather tube 200 and inlet pipe 300. At this time, even if the gas pressure in the fuel tank 100 acts on the valve member 8, the sum of the biasing force of the spring 5 and the dead weight of the valve member 8 is larger than the force received from the gas pressure. do not do. In this state shown in FIG. 11, the tip of the convex portion 92 is located above the upper end of the through hole 84, the flow of the gas flowing through the through hole 84 is not hindered, and the breather circuit functions stably. Even if liquid fuel is present in the housing 4, the valve member 8 is seated on the top of the protrusion 73, and a gap is formed between the valve member 8 and the reduced diameter portion 70, so that the valve member 8 is firmly fixed. It is prevented and the operation stability is high.

  During high-speed refueling, the gas pressure in the fuel tank 100 rises, and the pressure acts on the valve member 8 so that the valve member 8 starts to move in the direction approaching the convex portion 92. Then, the tip of the convex portion 92 wraps with the through hole 84, and the opening area of the through hole 84 gradually narrows as the valve member 8 rises. That is, the through hole 84 acts as the first valve portion, and the first valve portion is gradually closed. At the same time, the collar portion 81 also rises, but the collar portion 81 does not appear at the opening of the nipple portion 61 during the initial period.

  As the gas pressure in the fuel tank 100 rises, the opening area of the through hole 84 gradually narrows and resistance increases. Finally, the through hole 84 is closed by the convex portion 92, so that the lower side (tank of the tank 81) The difference between the gas pressure on the side) and the pressure (atmospheric pressure) on the upper side (fuel supply port side) from the flange 81 increases rapidly. Then, the valve member 8 rises at a stretch, and the opening of the nipple portion 61 and the gas inflow hole 72 communicate with each other as shown in FIG. That is, the collar part 81 functions as a second valve part, whereby the second valve part is fully opened.

  Therefore, according to the flow control valve of the present embodiment, the same effects as those of the first embodiment can be obtained. Further, even when the valve member 8 is seated on the reduced diameter portion 70, the valve member 8 is in the state where the tip of the convex portion 92 has entered the tip of the cylindrical portion 80 of the valve member 8. Therefore, it is reliably prevented that the movement is hindered by the interference. Moreover, since the diameter of the spring 5 can be made smaller than that of the first embodiment, the overall shape can be made more compact. When the flow rate control valve of this embodiment is assembled, the cylinder member 7, the valve member 8, the spring 5, and the seat plate 9 can be integrated in advance, so that the man-hours for welding the cover 6 and the cylinder member 7 are increased. Can be reduced as compared with the first embodiment.

(Example 5)
The flow control valve of this embodiment shown in FIG. 13 is used as a connector for connecting a breather tube and an inlet pipe of a breather circuit.

  This flow control valve includes a cover 6, a nipple 75 welded and fixed to the cover 6, a valve member 8, and a spring 5.

  The cover 6 has a bottomed cylindrical container-like part 60 and a connector part 65 projecting radially outward from the container-like part 60. From the bottom part of the container-like part 60, a convex part 66 having a concave part in the center and having the same shape as the seat plate 9 of the fourth embodiment projects. In addition, an outflow opening 67 communicating with the connector portion 65 is formed on the side wall of the container-like portion 60.

  The connector portion 65 is formed in a cylindrical shape, and two O-rings 68 are interposed therein. In addition, a plurality of locking claws 69 are swingably disposed in the outer opening so as to be able to reduce and expand the diameter.

  On the outer peripheral surface of the nipple 75, a plurality of fur-tree-shaped ring-shaped locking projections 76 are formed. On the opposite side, a cylindrical portion 77 having an enlarged inner diameter is formed, and the cylindrical portion 77 is fitted to the container-like portion 60 of the cover 6. Note that an opening 78 communicating with the outflow opening 67 is formed in the cylindrical portion 77. A stepped portion 79 is formed inside the intermediate portion. And it is welded and integrated with the cover 6 at the outer periphery of the intermediate part. The cylinder part 77 functions as a guide for moving the valve member 8 stably.

  The valve member 8 is the same as that of the fourth embodiment, and is similarly arranged. The valve member 8 is urged in the direction in which the valve member 8 is seated on the stepped portion 79 by the spring 5 arranged in the convex portion 66.

  In the flow control valve of this embodiment, the breather tube 200 is inserted and fixed to the nipple 75, and the pipe 301 protruding from the side wall of the inlet pipe 300 is inserted into the connector portion 65. A locking rod 302 is formed on the outer peripheral surface of the pipe 301, and the O-ring 68 is elastically contacted with the outer peripheral surface and the locking claw 69 is engaged with the locking rod 302, so that the pipe 301 is airtight to the connector portion 65. Fixed.

  According to the flow control valve of the present embodiment, during low-speed refueling, the gas in the fuel tank 100 flows into the nipple 75 from the breather tube 200, passes through the vent hole 83 and the through hole 84, and opens the opening 78 and the outflow opening 67. Passes through and flows into the inlet pipe 300. At this time, even if the gas pressure in the fuel tank 100 acts on the valve member 8, the sum of the urging force of the spring 5 and the weight of the valve member 8 is larger than the force received from the gas pressure. do not do. In this state, the tip of the convex portion 66 is located above the upper end of the through hole 84, the gas flowing through the through hole 84 is not hindered, and the breather circuit functions stably. And at the time of high-speed oil supply, the valve member 8 act | operates similarly to Example 4, and an effect equivalent to Example 4 is show | played.

  Furthermore, according to the flow control valve of the present embodiment, since the central axis of the inflow opening and the central axis of the outflow opening intersect with each other, it can be disposed as a connector at the connecting portion between the breather tube 200 and the inlet pipe 300. . Since the central axis intersects each other, the total length of the connector portion 65 and the diameter of the cover 6 can be made shorter than the connector described in, for example, Japanese Patent Application Laid-Open No. 2003-028010. The distance between 200 and the inlet pipe 300 can be shortened. Further, it is not necessary to bend the pipe 301 into an L shape. Therefore, the degree of freedom in design and arrangement is greatly improved.

  In this embodiment, the cylindrical portion 77 is fitted to the container-shaped portion 60, but the valve member 8 can be guided by the inner peripheral wall surface of the container-shaped portion 60 without forming the cylindrical portion 77. In addition, a connector portion can be formed in place of the nipple 75, and a nipple portion may be formed in place of the connector portion 65.

  The flow control valve of the present invention can be used for a breather nipple portion of a breather circuit, a connector provided in the breather circuit, a valve disposed between a cutoff valve and a canister, and the like.

It is sectional drawing of the flow control valve of one Example of this invention. It is explanatory drawing of the breather circuit provided with the flow control valve of one Example of this invention. It is explanatory drawing which shows the action | operation of the flow control valve of one Example of this invention. It is explanatory drawing which shows the action | operation of the flow control valve of one Example of this invention. It is explanatory drawing which shows the action | operation of the flow control valve of one Example of this invention. It is explanatory drawing which shows the relationship between the oil supply speed and breather gas flow volume in the flow control of the conventional breather circuit. It is explanatory drawing which shows the relationship between the gas pressure of a breather circuit and the breather gas flow volume in the conventional flow control valve, and the ideal relationship. It is a principal part expanded sectional view of the flow control valve of 2nd Example of this invention. It is a principal part expanded sectional view of the flow control valve | bulb of the 3rd Example of this invention. It is sectional drawing of the flow control valve | bulb of the 4th Example of this invention. It is explanatory drawing which shows the action | operation of the flow control valve of the 4th Example of this invention. It is explanatory drawing which shows the action | operation of the flow control valve of the 4th Example of this invention. It is sectional drawing of the flow control valve of the 5th Example of this invention.

Explanation of symbols

1: Cover 2: Tube member 3: Valve member
40: Clearance 41: Clearance

Claims (7)

A housing having an inflow opening through which fluid flows in and an outflow opening through which the fluid flowing in from the inflow opening flows out to the outside, and a convex portion protruding toward the inflow opening, and a substantially bottomed cylindrical shape opening upward None , a flow rate control valve comprising a valve member movably disposed in the housing, and a biasing means for biasing the valve member in a direction close to the inflow opening,
A first valve portion formed between the convex portion and the valve member 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 valve member and the housing and opens the communication between the inflow opening and the outflow opening as the valve member moves in a direction away from the inflow opening.
When the fluid 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 the pressure difference between the inflow opening side and the outflow opening side has a predetermined value. A flow rate control valve characterized in that the second valve portion is configured to open the communication between the inflow opening and the outflow opening at a stroke when exceeding. The flow control valve according to claim 1 , wherein the valve member is extrapolated to the convex portion, and the first valve portion is formed by an opening of the valve member side wall and the convex portion. The flow rate control valve according to claim 1, wherein the valve member has a flange portion, and the second valve portion is formed between the flange portion and the housing. The housing has a seat surface on which the valve member is seated when the fluid pressure on the inflow opening side is equal to or lower than a predetermined value, and at least one of the housing and the valve member is engaged with the other to engage the seat surface. The flow control valve according to claim 1, further comprising an engagement portion that forms a gap with the valve member. The flow rate control according to any one of claims 1 to 4 , wherein the housing is hermetically fixed to an upper portion of a fuel tank, the inflow opening communicates with a gas phase of the fuel tank, and the outflow opening communicates with a breather nipple. valve. The flow rate control valve according to claim 5 , wherein a cylindrical portion communicating with the inflow opening is formed in a lower portion of the housing.   The flow control valve according to claim 1, wherein a central axis of the inflow opening and a central axis of the outflow opening intersect each other.

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