JP2020051312A - Purge control valve - Google Patents

Abstract

To provide a purge control valve capable of reducing pulsation while curbing a reduction in a flow rate.SOLUTION: A purge control valve 4 comprises: an electromagnetic coil section 42 which drives a valve body 43; and a housing which stores the valve body 43 and the electromagnetic coil section 42 therein and has an inner passage 401a allowing evaporated fuel flowing therein to flow down therethrough and being opened and closed by the valve body 43. The housing also has: a chamber 6 positioned outside the inner passage 401a in the housing and a bulkhead separating the inner passage 401a from the chamber 6. The bulkhead is made up of a first passage wall 404 and a second passage wall 55 and has a communication passage 6a communicating the inner passage 401a with the chamber 6. The evaporated fuel in the inner passage 401a leaks into the chamber 6 through the communication passage 6a when the inner passage 401a is put in a closed valve state where the valve body 43 closes the same.SELECTED DRAWING: Figure 1

Description

  The disclosure in this specification relates to a purge control valve provided in a passage through which evaporated fuel flows toward an engine.

  Patent Literature 1 describes a purge control valve including a column member serving as a pulsation reducing unit in a fluid passage between an open end of an input port and a valve port. The column member has a cross-sectional shape having a small CD value in the normal flow direction from the input port to the valve port and a large CD value in the opposite flow direction. The decline has been suppressed.

JP 2008-291916 A

  According to Patent Literature 1, further improvement is required for the purge control valve from the viewpoint of suppressing a decrease in the flow rate of the fuel vapor.

  An object of the disclosure in this specification is to provide a purge control valve that can reduce pulsation while suppressing a decrease in flow rate.

  The embodiments disclosed in this specification employ different technical means from each other in order to achieve the respective objects. Further, the reference numerals in the parentheses described in the claims and this section are examples showing the correspondence with specific means described in the embodiment described below as one aspect, and limit the technical scope. is not.

  One of the disclosed purge control valves is a purge control valve (4; 104) installed in an evaporative fuel passage through which evaporative fuel desorbed from the canister (16) flows toward the engine (22). , An electromagnetic coil section (42) for driving the valve element (43), and an internal passage (401a) which contains the valve element and the electromagnetic coil section, and in which the evaporated fuel flowing in from the canister side flows down and is opened and closed by the valve element. A housing (40), a chamber chamber (6) provided inside the housing outside the internal passage, and a partition wall that forms the internal passage inside the housing and separates the internal passage from the chamber chamber ( 404, 55) and a communication passage (6a; 106a) which penetrates through the partition wall and communicates the internal passage with the chamber chamber, and which allows the evaporated fuel to escape from the internal passage into the chamber chamber. And, equipped with a.

  According to this purge control valve, by providing the communication passage that penetrates the partition wall that is the wall that forms the internal passage inside the housing, for example, when the pressure in the internal passage increases when the valve is closed, A part of the evaporated fuel can be released into the chamber. This makes it possible to attenuate the upstream pulsation by diffusing a part of the fluid into the chamber through the communication passage with respect to the pulsating flow propagating upstream in the valve closed state. The communication passage penetrates a partition wall that separates the chamber from the interior of the internal passage and the internal passage, and thus is a passage that is unlikely to have a flow resistance to a fluid flowing through the internal passage. As described above, it is possible to provide a purge control valve that can reduce pulsation while suppressing a decrease in the flow rate.

FIG. 1 is a schematic diagram illustrating an evaporative fuel processing system on which a purge control valve according to a first embodiment can be mounted. It is a longitudinal section of a purge control valve of a 1st embodiment. FIG. 4 is a cross-sectional view of a purge control valve. It is the graph which showed the relationship between the opening / closing state of a valve, and pressure fluctuation about embodiment goods and conventional goods. It is a longitudinal section of a purge control valve of a 2nd embodiment. FIG. 4 is a cross-sectional view of a purge control valve.

  Hereinafter, a plurality of embodiments for carrying out the present disclosure will be described with reference to the drawings. In each embodiment, portions corresponding to the items described in the preceding embodiment are denoted by the same reference numerals, and redundant description may be omitted. When only a part of the configuration is described in each embodiment, the other embodiments described above can be applied to other parts of the configuration. Not only the combination of the parts that clearly indicate that a combination is possible in each embodiment, but also the combination of the embodiments even if they are not explicitly described, unless there is a particular problem with the combination. Is also possible.

(1st Embodiment)
The first embodiment will be described with reference to FIGS. The evaporative fuel processing system shown in FIG. 1 supplies HC gas and the like in the fuel adsorbed to the canister 16 to the intake passage of the engine 22 and can prevent the evaporative fuel from the fuel tank 14 from being released to the atmosphere. It is. The evaporative fuel processing system includes a purge control valve 4 at a predetermined position in the evaporative fuel passage, which can adjust the flow rate of the evaporative fuel supplied to the intake passage. As shown in FIGS. 2 and 3, the purge control valve 4 includes a first housing 40 having an inflow port 41 and containing an electromagnetic coil portion 42, and a second housing 5 integrated with the first housing 40. At least. The assembly of the first housing 40 and the second housing 5 has a built-in valve body 43 and an electromagnetic coil section 42, and has an internal passage 401a in which the evaporated fuel flowing in from the canister 16 flows down and is opened and closed by the valve body 43. , Constituting a housing of the purge control valve 4. Each of the first housing 40 and the second housing 5 is formed of a resin material.

  Evaporated fuel introduced into the intake system 1 of the engine 22 is mixed with combustion fuel supplied to the engine 22 from an injector or the like and burned in a cylinder of the engine 22. In the intake system 1 of the engine 22, one end of the intake pipe 10 is connected to an intake manifold 20 of the engine 22, and a throttle valve 21 and a filter 13 are provided in the intake pipe 10. The fuel vapor purge system 2 is formed by connecting a fuel tank 14 and a canister 16 to an intake manifold 20 via pipes 15 and 17.

  The filter 13 is provided at an upstream portion of the intake pipe 10 and captures dust and dirt during intake. The throttle valve 21 is an intake air amount adjusting valve that adjusts an opening degree in an upstream portion of the intake manifold 20 in conjunction with an accelerator pedal to adjust an amount of intake air flowing into the intake manifold 20. The intake air passes through the filter 13 and the throttle valve 21 in order, flows into the intake manifold 20, is mixed with combustion fuel injected from an injector or the like so as to have a predetermined air-fuel ratio, and is combusted in the cylinder.

  The fuel tank 14 is a container for storing fuel such as gasoline. The fuel tank 14 is connected to an inflow portion 16 a of a canister 16 by a pipe 15. The canister 16 is a container in which an adsorbent such as activated carbon is sealed, and evaporative fuel generated in the fuel tank 14 is taken in from the inflow portion 16a via the pipe 15 and is temporarily adsorbed on the adsorbent. The canister 16 is provided with a suction portion 16b for sucking fresh outside air. By providing the canister 16 with the suction portion 16b, the atmospheric pressure acts inside the canister 16. The canister 16 can desorb the evaporated fuel adsorbed on the adsorbent into fresh air that has been sucked.

  For example, a valve module is provided integrally with the suction portion 16b. The valve module has a built-in canister close valve that opens and closes an intake section for inhaling fresh fresh air, and an internal pump that can release gas to the atmosphere or inhale the atmosphere. I have. When the canister 16 includes the canister close valve, the atmospheric pressure can be applied to the inside of the canister 16. The canister 16 can easily desorb, that is, purge, the evaporated fuel adsorbed on the adsorbent by the inhaled fresh air.

  The canister 16 is provided with an outflow portion 16c through which the evaporated fuel released from the adsorbent flows out. One end of the pipe 17 is connected to the outflow portion 16c. The other end of the pipe 17 is connected between the intake manifold 20 and the throttle valve 21 in the intake pipe 10. The passage in the pipe 17 is also referred to as a fuel inflow passage through which fuel flows into the purge control valve 4. In the pipe 17, between the canister 16 and the intake pipe 10, a purge control valve 4 and a check valve device 3 are installed in this order from the upstream side.

  The purge control valve 4 is an opening / closing unit that opens and closes the evaporated fuel passage, and has a function of permitting and preventing supply of the evaporated fuel flowing out of the canister 16 to the engine 22. As shown in FIG. 2, the purge control valve 4 includes a valve body 43 and an electromagnetic coil section 42 including a coil section 420, a movable core 422, a fixed core 423, a spring 424, and the like. The purge control valve 4 opens and closes the internal passage 401a by driving the valve body 43 in accordance with the balance between the electromagnetic force generated when the coil portion 420 is energized and the biasing force of the spring 424.

  The purge control valve 4 includes a first housing 40 forming an internal passage 401a. The purge control valve 4 normally maintains a state in which the internal passage 401 a forming the fuel vapor passage is closed, and when the coil portion 420 is energized, the electromagnetic force overcomes the elastic force of the spring 424 and the valve body 43 The internal passage 401a is opened away from the valve seat 54. The control device controls the ratio of the on-time to the time of one cycle formed by the on-time and the off-time of the energization, that is, the duty ratio to energize the coil unit. The purge control valve 4 is also called a duty control valve. By this energization control, the flow rate of the evaporated fuel flowing through the internal passage 401a is adjusted.

  The check valve device 3 is a fuel vapor passage from the canister 16 to the intake pipe 10, and is a valve for preventing a backflow installed between the purge control valve 4 and the intake manifold 20. The check valve device 3 allows the natural flow of the evaporated fuel from the passage on the purge control valve 4 side to the passage on the intake pipe 10 side in the evaporated fuel passage, Backflow of evaporated fuel to the passage of the fuel cell is prevented. The check valve device 3 includes a valve body that operates to open a flow path with the original flow of the evaporative fuel and close the flow path with the reverse flow of the evaporative fuel.

  When the purge control valve 4 is opened by the control device during traveling of the vehicle, a difference is generated between the negative pressure in the intake manifold 20 generated by the suction action of the piston and the atmospheric pressure applied to the canister 16. Due to this pressure difference, the vapor fuel adsorbed in the canister 16 flows down the purge control valve 4 and the check valve device 3 in order, and is sucked into the intake manifold 20.

  The evaporated fuel sucked into the intake manifold 20 is mixed with the original fuel for combustion supplied to the engine 22 from an injector or the like, and burned in the cylinder of the engine 22. Further, in the cylinder of the engine 22, the air-fuel ratio, which is a mixture ratio of the fuel for combustion and the intake air, is controlled to be a predetermined air-fuel ratio. The control device performs duty control on the valve opening time and the valve closing time of the purge control valve 4 to adjust the purge amount of the fuel vapor so that a predetermined air-fuel ratio is maintained even when the fuel vapor is purged.

  The first housing 40 has a bottom on one end side, has a downstream opening on the other end opposite to the one end, and further has a downstream opening on the side with respect to the bottom. Has a tubular inflow port 41 extending in a direction intersecting with. The inflow port 41 forms an inflow passage 41a through which the evaporated fuel flowing out to the internal passage 401a flows. The inflow port 41 has an inflow passage 41a therein for communicating the internal passage 401a of the first housing 40 with the passage in the pipe 17 on the canister 16 side. The first housing 40 houses a valve body 43 for opening and closing the internal passage 401a, and an electromagnetic coil unit 42 for driving the valve body 43. The electromagnetic coil section 42 is integrally provided at the bottom of the first housing 40.

  The downstream opening has a rectangular shape. A flange portion 401b radially protruding radially outward is provided on the entire periphery of the downstream opening. The outflow side tubular portion 401 is a tubular portion having a radially protruding flange portion 401b formed on the outer peripheral edge of the opening located at the downstream end, and forming a rectangular space upstream of the opening. The flange portion 401b is a portion that is joined to the flange portion 52 of the second housing 5.

  The second housing 5 of the purge control valve 4 is a member that allows the pipe 17 on the intake pipe 10 side to communicate with the first housing 40. The second housing 5 includes a flange portion 52 that is connected to the first housing 40 by welding or bonding, and an outflow port 51 that projects from the flange portion 52 in a direction orthogonal to the flange portion 52. The outflow port 51 has an outflow passage 51a through which the evaporated fuel flowing out of the internal passage 401a flows. The outflow port 51 is connected to the pipe 17 in the evaporative fuel processing system and communicates with the check valve device 3.

  The second housing 5 further includes a cylindrical portion 53 protruding inside the flange portion 52 on the side opposite to the outflow port 51. The tubular portion 53 has a valve seat 54 on the distal end side with which the valve body 43 contacts. The tubular portion 53 has a shape that protrudes into the first housing 40 from the opening inside the flange portion 401b, and the inside where the fuel vapor flows in from the internal passage 401a when the valve body 43 is in the valve open state. A passage 53a is provided inside.

  The flange portion 52 is a portion that radially protrudes radially outward over the entire circumference of a connection portion where the tubular portion 53 and the outflow port 51 are connected. The flange portion 52 is a portion that is joined to the flange portion 401b of the first housing 40. The flange portion 52 is integrally joined to the flange portion 401b in a state of being overlapped with the flange portion 401b.

  The housing of the purge control valve 4 has an internal passage 401a and a chamber 6 inside. The chamber 6 is provided outside the internal passage 401a. The chamber 6 is not a space provided in the middle of the internal passage 401a. The chamber 6 is provided so as to cover a range up to the valve body 43 in the internal passage 401a from both sides. The chamber 6 is further provided so as to cover a portion of the internal passage 401a that is surrounded by the valve body 43. The volume of the chamber 6 is set to be larger than the volume of the internal passage 401a in the housing. The volume of the chamber 6 is preferably at least twice as large as the volume of the internal passage 401a in the housing.

  The housing of the purge control valve 4 has a partition wall that partitions the internal passage 401 a and the chamber 6. The partition wall is also a wall that forms an internal passage 401 a inside the housing of the purge control valve 4. As shown in FIG. 3, the partition wall is formed to include a pair of opposing walls provided on the upstream side and a cylindrical wall connected to a downstream end of the pair of opposing walls. .

  The pair of opposed wall portions includes two walls facing each other at an interval, and extends from the upstream end of the internal passage 401a toward the downstream valve seat 54. The pair of opposed walls form a passage extending from the downstream end of the inflow passage 41a to the upstream end of the cylindrical wall in the internal passage 401a. The cylindrical wall portion is a C-shaped wall portion that surrounds the valve seat 54 and the internal passage 53a in the cylindrical portion 53 and is connected to a pair of opposed wall portions.

  The partition wall is formed by a first passage wall 404 provided in the first housing 40 and a second passage wall 55 provided in the second housing 5. The first passage wall 404 is a wall portion extending from the electromagnetic coil portion 42 side toward the distal end portion. The distal end portion on the flange portion 401b side is opened, and forms a wall portion of the partition wall on the electromagnetic coil portion 42 side. The second passage wall 55 is a wall portion extending from the outflow port 51 side toward the distal end portion, and the position and shape of the distal end portion match the distal end portion of the first passage wall 404, and the second passage wall 55 on the outflow port 51 side in the partition wall. Construct the wall. The first passage wall 404 and the second passage wall 55 are assembled to each other in the axial direction.

  The first passage wall 404 includes a pair of first cylindrical wall portions 404b forming a wall portion of the cylindrical wall portion on the side of the electromagnetic coil portion 42 and a pair of first cylindrical wall portions 404b forming a wall portion of a pair of opposing wall portions on the side of the electromagnetic coil portion 42. And the first opposed wall portion 404c. The first cylindrical wall portion 404b and the pair of first opposing wall portions 404c are integrally formed to form a wall portion of the partition wall on the electromagnetic coil portion 42 side. The second passage wall 55 includes a pair of second cylindrical wall portions forming a wall portion on the electromagnetic coil portion 42 side of the cylindrical wall portion, and a pair of second cylindrical wall portions forming a wall portion on the electromagnetic coil portion 42 side of the pair of opposed wall portions. A second opposed wall portion. The second cylindrical wall portion and the pair of second opposing wall portions integrally form a wall portion on the outflow port 51 side of the partition wall.

  At the tip of the first passage wall 404, a recess 404a that is recessed toward the electromagnetic coil portion 42 from the surroundings is provided. A recessed portion 55 a that is recessed toward the outflow port 51 from the surroundings is provided at the distal end of the second passage wall 55. The recessed portion 404a and the recessed portion 55a are semicircular recessed portions, respectively, and are provided at positions where the first passage wall 404 and the second passage wall 55 are matched with each other in a combined state. Is formed. The communication passage 6a is a passage that penetrates through the partition wall and communicates the internal passage 401a with the chamber chamber 6. The communication passage 6a functions as a passage for allowing the evaporated fuel to escape from the internal passage 401a to the chamber chamber 6 when the valve body 43 closes the internal passage 401a. The fluid leaks from the internal passage 401a to the chamber 6 through the communication passage 6a, so that the pressure in the internal passage 401a can be reduced. The chamber chamber 6 provides a chamber volume that has an effect of reducing pulsation generated in the purge control valve 4.

  As shown in FIGS. 2 and 3, the communication passage 6 a is provided in a cylindrical wall portion surrounding the valve seat 54 and the internal passage 53 a in the cylindrical portion 53. The chamber 6 includes a first chamber 6b provided so as to surround the cylindrical wall, and a second chamber 6c provided on both outer sides of the pair of opposed walls. The first chamber 6b and the second chamber 6c communicate with each other. The communication passage 6a is provided at a position farther from the upstream end of the internal passage 401a than the valve body 43 on the partition wall. The communication passage 6a is provided on the partition wall on the side opposite to the upstream end of the internal passage 401a with respect to the valve body 43. According to this configuration, it is possible to obtain an effect that the fluid hardly leaks to the chamber 6 when the valve is open, and leaks to the chamber 6 so as to reduce the increased pressure around the valve element 43 when the valve is closed. In the closed state, the fluid in the internal passage 401a flows out to the first chamber 6b through the communication passage 6a, and can diffuse to the second chamber 6c located outside the pair of opposed walls.

  The distance XB between the valve seat 54 and the first cylindrical wall portion 404b in the radial direction of the cylindrical wall portion is determined by the first cylindrical wall portion 404b and the outflow side cylindrical portion 401 of the first housing 40 in the radial direction. Is set to be smaller than the interval XA. According to this configuration, it is possible to prevent the fluid leaking into the chamber chamber 6 through the communication passage 6a at the time of closing the valve from colliding with the outflow-side tubular portion 401 and flowing back through the communication passage 6a. Accordingly, a flow that diffuses the fluid leaked into the chamber 6 widely into the chamber 6 can be formed, thereby contributing to a reduction in pulsation.

  The communication passage 6a penetrating the partition wall may be configured as an opening formed by a recess formed at one end of the first passage wall 404 and the second passage wall 55. That is, the concave portion at the distal end may be provided in one of the first passage wall 404 and the second passage wall 55.

  The purge control valve 4 is fixed to a member on the vehicle side by, for example, a bolt screwed into a nut embedded in the first housing 40. The movable core 422 is made of a material that transmits magnetism, for example, a magnetic material. The movable core 422, which is a cylindrical body, surrounds the shaft member 425 and the spring 424 inserted from the open end. The valve body 43 is formed of an elastically deformable material such as rubber. The valve element 43 is mounted on the movable core 422 such that the head of the movable core 422 is sandwiched between the base and the valve section from both sides, and is integrated with the movable core 422.

  The fixed core 423 slidably supports the movable core 422 that moves in the axial direction against the urging force of the spring 424 by the electromagnetic force. The spring 424 is provided on the cylindrical portion of the movable core 422 in a state where one end in the axial direction contacts the shaft member 425 fixed to the fixed core 423 and the other end in the axial direction contacts the head of the movable core 422. It is provided inside. Therefore, the spring 424 provides an urging force for moving the movable core 422 to the valve seat 54 side. The fixed core 423 fixes the shaft member 425 and is assembled to the bobbin 421 to be fitted outside. The fixed core 423, the shaft member 425, the movable core 422, and the valve body 43 are installed such that their axes are coaxial. The shaft member 425 is formed of, for example, polybutylene terephthalate or polybutylene terephthalate reinforced with glass fibers. The fixed core 423 and the movable core 422 are made of a material that transmits magnetism. The fixed core 423 is formed of, for example, carbon steel for cold heading.

  A filter may be provided inside the first housing 40 on the upstream side of the internal passage 401a.

  As shown in FIG. 2, the first housing 40 includes a connector 402 extending outward at a bottom on one end side where the electromagnetic coil portion 42 is installed. The connector 402 has a terminal 402 a for energizing the coil section 420. The connector 402 is a resin molded part that supports a terminal 402 a that projects from the inside of the first housing 40 to the outside through the bottom. The terminal 402 a is a current-carrying terminal that is electrically connected to the coil unit 420. The connector 402 is connected to a power supply side connector for supplying power from a power supply unit and a current control device. When the connector 402 is connected to the power supply side connector and the terminal 402 a is electrically connected to a current control device or the like, the purge control valve 4 can control the current flowing through the coil section 420.

  FIG. 4 is a graph showing the relationship between the open / close state of the valve element 43 and the pressure fluctuation for the purge control valve 4 and the conventional purge control valve. The conventional product is a purge control valve having no chamber, and when the valve is closed, a flow in which a pulsating flow flows backward toward the upstream is generated. The time axis is set on the horizontal axis. On the vertical axis, a signal voltage value indicating an energized state and a non-energized state, and a pressure in the fluid passage are set. In FIG. 4, an alternate long and short dash line indicates an energized state of the electromagnetic coil unit 42. A waveform portion protruding in a rectangular shape indicates that the purge control valve is open, and when the signal voltage is zero, it indicates that the purge control valve is closed.

  In FIG. 4, a broken line indicates a pressure fluctuation of the fluid passage in the conventional purge control valve, and a solid line indicates a pressure fluctuation of the fluid passage in the purge control valve 4. For both the purge control valve 4 and the conventional purge control valve, it has been confirmed that the pressure fluctuation increases sharply when the valve is closed from the open state, and attenuates over time. Although the magnitude of the pressure fluctuation immediately after the closing is similar between the purge control valve 4 and the conventional purge control valve, it has been confirmed that the purge control valve 4 is greatly attenuated thereafter. Therefore, according to the purge control valve 4, it is considered that the effect of reducing the pulsation after the valve is closed is greater than that of the conventional purge control valve.

  Next, the operation and effect provided by the purge control valve 4 of the first embodiment will be described. The purge control valve 4 includes an electromagnetic coil part 42 for driving the valve element 43, a valve element 43 and an electromagnetic coil part 42, and an internal passage opened and closed by the valve element 43 when the fuel vapor flowing in from the canister 16 flows down. And a housing having 401a. Inside the housing, a chamber 6 is provided outside the internal passage 401a. The housing includes a partition wall that defines the internal passage 401 a and a partition wall that partitions the internal passage 401 a from the chamber 6. The purge control valve 4 is a communication passage that penetrates through the partition wall and communicates the internal passage 401a with the chamber chamber 6, and includes a communication passage 6a that allows evaporated fuel to escape from the internal passage 401a to the chamber chamber 6.

  According to the purge control valve 4, by providing the communication passage 6a penetrating the partition wall forming the internal passage 401a, when the pressure of the internal passage 401a increases in a valve closed state or the like, the evaporation present in the internal passage 401a is provided. Part of the fuel can escape to the chamber 6. Thus, with respect to the pulsating flow propagating upstream in the valve closed state, the pulsation flowing upstream can be attenuated by diffusing a part of the fluid into the chamber 6 through the communication passage 6a. Since the communication passage 6a penetrates a partition wall that separates the chamber passage 6 outside the internal passage 401a from the internal passage 401a, the communication passage 6a is a passage that hardly causes resistance to the fluid flowing through the internal passage 401a. Further, after the pressure of the fluid leaking into the chamber chamber 6 is reduced, the fluid returns to the internal passage 401a via the communication passage 6a with the fluid flowing backward in the internal passage 401a. The return of the fluid to the internal passage 401a contributes to the damping of the pulsation to the upstream side. Thus, according to the purge control valve 4, pulsation can be reduced while suppressing a decrease in the flow rate.

  The communication passage 6a is provided at a position farther from the upstream end of the internal passage 401a than the valve body 43. According to this configuration, when the valve is closed, the fluid located at a position closer to the upstream end of the internal passage 401a than the valve body 43 does not easily pass through the communication passage 6a. It is located at a position where the flow of the fluid flowing down 401a is not easily disturbed. Thus, the communication path 6a can suppress the fluid resistance in the valve open state, so that it has a pulsation reducing effect and also contributes to suppressing a decrease in the flow rate.

  The partition wall includes a pair of opposing walls extending from the upstream end of the internal passage 401a toward the valve seat 54, and a cylindrical wall surrounding the valve seat 54 and connected to the pair of opposing walls. Is formed. According to this configuration, the chamber chamber 6 can be provided outside the internal passage wall formed by the pair of opposed wall portions and the cylindrical wall portion. According to this, the chamber chamber 6 can be formed so as to surround the internal passage wall, the chamber chamber 6 having a large volume can be secured inside the housing, and the purge control having a high pulsation reduction effect can be secured. A valve 4 can be provided.

  The communication passage 6a is a passage penetrating through the cylindrical wall. According to this configuration, when the valve is closed, the fluid existing inside the cylindrical wall portion easily passes through the communication passage 6 a, so that the energy in which the fluid existing in the vicinity of the valve body 43 flows backward is transmitted to the chamber 6. You can escape. As a result, the energy for causing the fluid to flow backward in the valve-closed state is reduced, which contributes to the reduction of pulsation accompanying the backflow.

  The housing includes a first housing 40 having a built-in electromagnetic coil portion 42, and a second housing 5 having a valve seat 54 and integrally assembled with the first housing 40 in the axial direction of the valve element 43. The partition wall is formed by a first passage wall 404 provided in the first housing 40 and a second passage wall 55 provided in the second housing 5 and assembled with the first passage wall 404 in the axial direction. Have been. According to this configuration, the partition wall is formed by forming the first passage wall 404 in the first housing 40 so as to extend in the axial direction and the second passage wall 55 in the second housing 5 so as to extend in the axial direction. Can be formed, and the purge control valve 4 with reduced manufacturing cost can be provided.

  The partition wall is formed by the first passage wall 404 and the second passage wall 55 that is assembled to the first passage wall 404 in the axial direction. The communication passage 6a is preferably an opening formed by a concave portion formed at at least one end of the first passage wall 404 and the second passage wall 55. According to this configuration, a communication path 6a that is opened by the recess can be formed at a part of the joint between the first passage wall 404 and the second passage wall 55 that are assembled in the axial direction. Thereby, when the first housing 40 and the second housing 5 are resin molded products, the communication passage 6a penetrating the partition wall can be formed without using a portion that slides inside the mold. This also contributes to reducing the manufacturing cost of the purge control valve 4.

  It is preferable that the volume of the chamber 6 be set larger than the volume of the internal passage 401a. According to this configuration, when a part of the pulsating flow propagating upstream in the valve closed state diffuses into the chamber 6 via the communication passage 6a, the diffusion of the fluid into the chamber 6 can be promoted. . Thereby, the effect of attenuating the pulsation to the upstream side can be enhanced.

(2nd Embodiment)
A second embodiment will be described with reference to FIGS. Configurations, operations, and effects that are not particularly described in the second embodiment are the same as those in the first embodiment, and only differences from the first embodiment will be described below.

  The second embodiment is different from the first embodiment in the position of the communication path 106a. As shown in FIGS. 5 and 6, the purge control valve 104 includes at least a first housing 140 and a second housing 105 integrated with the first housing 140. A recess 404a that is recessed toward the electromagnetic coil portion 42 from the surroundings is provided at a front end portion of the first passage wall 404 in a range that forms the opposed wall portion. A recessed portion 55 a that is recessed toward the outflow port 51 from the surroundings is provided at a distal end portion of the second passage wall 55 in a range that forms the opposed wall portion. The recessed portion 404a and the recessed portion 55a are semicircular recessed portions, respectively, and are provided at positions where the first passage wall 404 and the second passage wall 55 are matched with each other in a combined state. Is formed. The communication passage 106a is a passage that penetrates through the partition wall and communicates the internal passage 401a with the chamber 6. The communication path 106a has the same function as the communication path 6a of the first embodiment. In the closed state, the fluid in the internal passage 401a flows out to the second chamber 6c through the communication passage 106a, and can be diffused to the first chamber 6b located outside the cylindrical wall. The fluid leaks from the internal passage 401a to the chamber 6 through the communication passage 106a, so that the pressure in the internal passage 401a can be reduced.

  As shown in FIGS. 5 and 6, the communication path 106a is provided on one or both of the integrated opposing walls. The communication passage 106a is provided at a position closer to the upstream end of the internal passage 401a than the valve body 43 in the partition wall. The communication passage 106a is provided near the upstream end of the internal passage 401a on the partition wall. According to this configuration, the fluid is less likely to leak into the chamber 6 through the communication passage 106a when the valve is open, and the backflow flowing out of the purge control valve 4 is released to the chamber 6 when the valve is closed to reduce the backflow energy. Play.

  The communication passage 106a penetrating the partition wall may be configured as an opening formed by a concave portion formed at one end of the first passage wall 404 and the second passage wall 55. That is, the concave portion at the distal end of the communication path 106a may be provided in one of the first passage wall 404 and the second passage wall 55.

  According to the second embodiment, the communication passage 106a is preferably located closer to the upstream end of the internal passage 401a than the valve body 43. According to this configuration, when the valve is closed, the fluid present at a position closer to the upstream end of the internal passage 401a than the valve body 43 easily passes through the communication passage 106a. According to the communication passage 106 a at this position, the energy of the pulsating flow that has grown larger from the purge control valve 4 toward the outside than in the vicinity of the valve body 43 can be released to the chamber 6.

  The communication passage 106a is a passage that penetrates at least one of the pair of opposed wall portions. According to the communication passage 106a penetrating at least one of the opposed wall portions, when the valve is closed, the fluid present at a position closer to the upstream end of the internal passage 401a than the valve body 43 can be released to the chamber chamber 6. . Further, since the communication passage 106a penetrates the opposed wall portion along which the fluid flows down, the fluid resistance in the valve-open state can be suppressed, so that the pulsation is reduced and the flow rate is suppressed. .

(Other embodiments)
The disclosure of this specification is not limited to the illustrated embodiments. The disclosure includes the illustrated embodiments and variations based thereon based on those skilled in the art. For example, the disclosure is not limited to the combination of the components and elements shown in the embodiment, and can be implemented with various modifications. The disclosure can be implemented in various combinations. The disclosure may have additional parts that can be added to the embodiments. The disclosure includes those in which the components and elements of the embodiments are omitted. The disclosure encompasses the replacement or combination of parts, elements, between one embodiment and another. The disclosed technical scope is not limited to the description of the embodiments. The disclosed technical range is shown by the description of the claims, and should be construed to include all modifications within the meaning and scope equivalent to the description of the claims.

  The purge control valve capable of achieving the object disclosed in the specification is not a flow control device applied only to the evaporative fuel processing system disclosed in the above embodiment. This purge control valve can be applied, for example, to a system that can introduce evaporative fuel that has passed through the purge control valve into a passage upstream of the supercharger and can perform a purge during supercharging.

  The purge control valve capable of achieving the object disclosed in the specification includes not only a structure including a first housing having an inflow port, but also an apparatus having a structure in which an inflow port and a first housing, which are separate components, are integrally connected. Contains.

  The purge control valve capable of achieving the object disclosed in the specification is not limited to the example shown in the above embodiment. Further, the components connected to the purge control valve are not limited to the example shown in the above-described embodiment.

4,104: purge control valve; 5,105: second housing (housing)
Reference Signs List 6: chamber chamber, 6a, 106a: communication passage 16: canister, 22: engine 40, 140: first housing (housing), 42: electromagnetic coil part 43: valve body, 55: second passage wall (partition wall)
401a: internal passage; 404: first passage wall (partition wall)

Claims (9)

A purge control valve (4; 104) installed in a fuel vapor passage through which the fuel vapor desorbed from the canister (16) flows toward the engine (22);
An electromagnetic coil section (42) for driving the valve element (43);
A housing (40) having the valve body and the electromagnetic coil unit therein and having an internal passageway (401a) through which the evaporated fuel flowing in from the canister side flows down and is opened and closed by the valve body;
A chamber chamber (6) provided outside the internal passage inside the housing;
A partition wall (404, 55) which is a wall forming the internal passage inside the housing and partitions the internal passage and the chamber;
A communication passage (6a; 106a) that penetrates through the partition wall and communicates the internal passage with the chamber chamber, the communication passage allowing the fuel vapor to escape from the internal passage to the chamber chamber;
A purge control valve.   The purge control valve according to claim 1, wherein the communication passage is provided at a position farther from the upstream end of the internal passage than the valve body.   The purge control valve according to claim 1, wherein the communication passage is located closer to an upstream end of the internal passage than the valve body.   The partition wall includes a pair of opposed wall portions (404c) extending from an upstream end of the internal passage toward the valve seat (54), and a cylinder surrounding the valve seat and connected to the pair of opposed wall portions. The purge control valve according to claim 1, wherein the purge control valve is formed with a wall-shaped portion (404 b).   The purge control valve according to claim 4, wherein the communication passage is a passage penetrating the cylindrical wall.   The purge control valve according to claim 4, wherein the communication passage is a passage that penetrates at least one of the pair of opposed wall portions. The housing has a first housing (40, 140) containing the electromagnetic coil portion and a valve seat (54), and is integrally assembled with the first housing in the axial direction of the valve body. 2 housings (5, 105),
The partition wall includes a first passage wall (404) provided in the first housing, and a second passage wall provided in the second housing and assembled in the axial direction to the first passage wall. The purge control valve according to claim 1, wherein the purge control valve is formed by:   The purge control valve according to claim 7, wherein the communication passage is an opening formed by a recess (55a, 404a) formed at at least one end of the first passage wall and the second passage wall. .   The purge control valve according to any one of claims 1 to 8, wherein a volume of the chamber is set to be larger than a volume of the internal passage.

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