JP2012097711A - Solenoid valve and evaporated fuel processing device having the solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve control accuracy of a flow rate, and to improve sealability between a valve member and a valve seat, while having the bidirectional relief function.SOLUTION: A flow control valve 38 includes first to third valve members 96, 97 and 98 for opening/closing a fluid passage 94 of a valve housing 70, springs 118, 112 and 103 for urging the respective valve members, and a step motor 53 for opening the first valve member 96 and the second valve member 97 stepwise, and is constituted so that the second valve member 97 or the third valve member 98 is opened by differential pressure between upstream side internal pressure and downstream side internal pressure. Seal members 120, 122b and 122c are provided between the valve members 96, 97 and 98 and the valve seats 97b, 98b and 100. The seal members 120, 122b and 122c and the springs 118, 112 and 103 for urging the valve members 96, 97 and 98 corresponding to the respective seal members, are arranged with the positional relationship corresponding to the axial direction.

Description

  The present invention relates to a solenoid valve and a fuel vapor processing apparatus including the solenoid valve.

A conventional example of a solenoid valve (see, for example, Patent Document 1) will be described. FIG. 10 is a cross-sectional view showing the open state of the solenoid valve.
As shown in FIG. 10, the electromagnetic valve 532 controlled to be opened and closed by the control device 522 is provided in a passage 528 connecting the fuel tank main body and the canister, and is opened when refueling. Further, when the internal pressure of the fuel tank main body side 532D is lowered by a predetermined value or more compared to the internal pressure of the canister side 532A during parking, the valve body 532C of the electromagnetic valve 532 is opened against the urging force of the spring 532B. The Further, when the internal pressure of the fuel tank main body side 532D is increased by a predetermined value or more compared to the internal pressure of the canister side 532A, the valve body 534A of the relief valve 534 provided in the valve body 532C becomes the biasing force of the spring 534B. The valve is opened against it. Therefore, the solenoid valve 532 has a bidirectional relief function.

JP 2002-317707 A

  According to the electromagnetic valve 532, there is a problem that the flow rate control accuracy is low because the valve member 532C is the only valve member that is controlled to open and close by the control device 522. Further, the valve body 532C is pressed against the valve seat 536A formed in the valve housing 536 by the urging force of the spring 532B, thereby sealing between the valve seat 536A and the valve body 532C. Further, the relief valve 534 is pressed against the valve seat 538 formed on the valve body 532C by the urging force of the spring 534B, thereby sealing between the valve seat 538 and the relief valve 534. However, it is difficult to accurately form the flatness of the contact surfaces between the valve seats 536A and 538, the valve body 532C, and the relief valve 534, and both (between 536A and 532C, 538 and 534). ) Has a problem of low sealing performance.

  The problem to be solved by the present invention is an electromagnetic valve capable of improving the flow rate control accuracy and improving the sealing performance between the valve member and the valve seat while having a bidirectional relief function, and the electromagnetic valve thereof. An object of the present invention is to provide an evaporative fuel processing apparatus including a valve.

The above-mentioned problems can be solved by an electromagnetic valve having the gist of the structure described in the claims and an evaporative fuel processing apparatus provided with the electromagnetic valve.
According to the electromagnetic valve described in claim 1, a valve housing that forms a fluid passage having a first passage portion and a second passage portion that communicate with each other, and a biasing force of the first biasing means that opens and closes the fluid passage. The first valve member urged with the direction along the fluid flow direction from the first passage portion to the second passage portion as a closing direction, and the first urging force of the second urging means opens and closes the fluid passage and A second valve member biased with the same direction as the closing direction of the valve member as the closing direction, an electromagnetic drive unit having an actuating member for opening the first valve member and the second valve member in stages, and opening and closing the fluid passage And a third valve member urged by the urging force of the third urging means with the direction opposite to the closing direction of the first valve member as a closing direction, and the internal pressure of the first passage portion becomes the internal pressure of the second passage portion. In contrast, when it becomes larger than a predetermined value, the third valve member opens against the urging force of the third urging means. When the internal pressure of the first passage portion becomes smaller than the internal pressure of the second passage portion by a predetermined value or more, at least one valve member of the first valve member and the second valve member is the urging means. A valve that opens against the urging force of at least one of the first valve member, the second valve member, and the third valve member, and a valve seat on which the valve member can be seated and separated. A seal member that elastically seals between the two when the valve member is closed is provided, and the seal member and the biasing means that biases the valve member corresponding to the seal member correspond to each other in the axial direction. It is arranged with a positional relationship.
With this configuration, when the internal pressure of the first passage portion becomes larger than the internal pressure of the second passage portion by a predetermined value or more, the third valve member opens against the urging force of the third urging means. By controlling the pressure, the differential pressure between the internal pressure of the first passage portion and the internal pressure of the second passage portion can be controlled to a predetermined value or less. In addition, when the internal pressure of the first passage portion becomes smaller than the internal pressure of the second passage portion by a predetermined value or more, at least one of the first valve member and the second valve member is attached to the biasing means. By opening the valve against the force, the differential pressure between the internal pressure of the first passage portion and the internal pressure of the second passage portion can be controlled to a predetermined value or less. Therefore, a bidirectional relief function can be provided.
In addition, since the first valve member and the second valve member are opened stepwise by the actuating member of the electromagnetic drive unit, the flow rate control accuracy is improved compared to the conventional solenoid valve (see Patent Document 1). can do.
Further, when the valve member is closed between at least one of the first valve member, the second valve member, and the third valve member and the valve seat on which the valve member can be seated and separated. A seal member that elastically seals between the two is provided, and the seal member and a biasing means that biases the valve member corresponding to the seal member are arranged with a positional relationship corresponding to the axial direction. The sealing performance between the valve member and the valve seat is improved by applying the urging force of the urging means to the seal portion by the seal member between the member and the valve seat with a positional relationship corresponding to the axial direction. can do. This is effective as a solenoid valve that requires high airtightness.

  Further, according to the electromagnetic valve described in claim 2, the contact portion of the valve member or the valve seat to which the seal member is contacted / separated is formed in a thin plate shape in the contact / separation direction of the seal member by resin molding. is there. If comprised in this way, the amount of shrinkage | contraction deformation by resin molding of the contact part of the valve member or valve seat which a seal member will contact / separate can be made small, and generation | occurrence | production of sink can be prevented. Thereby, since the flatness of the contact surface of the contact part which a seal member contacts is improved, the sealing performance between a seal member and a contact part can be improved.

  In addition, according to the electromagnetic valve described in claim 3, the seal body in which the inner ring side seal member and the outer ring side seal member to which the abutting portion of the valve member or the valve seat comes into contact is separated and formed integrally in a double ring shape. It is provided. With this configuration, since the inner ring side seal member and the outer ring side seal member are provided with a seal body integrally formed in a double ring shape, the coaxiality of both seal members is improved. The sealing property between the contact portions can be improved. In addition, the contact part which both seal members contact may be one member or two members.

  According to the electromagnetic valve recited in claim 4, the urging means for urging the valve member to which the seal body is attached has an urging force between the inner ring side seal member and the outer ring side seal member. It arrange | positions so that it may act on an intermediate part. If comprised in this way, since the urging | biasing force of the urging means which acts on both the sealing members of a sealing body is equalized, the sealing performance between both the sealing members and a contact part can be improved.

  According to the electromagnetic valve described in claim 5, an annular third valve seat on which the third valve member can be seated and separated is formed in the valve housing, and the second valve member is formed on the third valve member. An annular second valve seat that can be seated and separated and a third valve portion that can be seated and separated from the third valve seat are formed in a common plate-like portion, A seal body is provided on the plate-like portion of the third valve member, and the inner ring side seal member of the seal body is a second seal member that contacts and separates the second valve portion of the second valve member, and the outer ring of the seal body The side seal member is a third seal member that contacts and separates from the third valve seat. If comprised in this way, while making the inner ring side seal member of the seal body provided in the plate-shaped part of the 3rd valve member into the 2nd seal member, the outer ring side seal member of the seal body is made into the 3rd seal member. Thus, the sealing performance between the second sealing member and the second valve portion of the second valve member is improved, and the sealing performance between the third sealing member and the third valve seat of the valve housing is improved. Can do.

  According to the electromagnetic valve described in claim 6, the second urging means for urging the second valve member and the urging means for urging the third valve member are opposed to each other. It arrange | positions so that it may act on the site | part adjacent to the direction and the direction which cross | intersects the opposing direction. If comprised in this way, since the urging | biasing force of a 2nd urging means and the urging | biasing force of a 3rd urging | biasing means can be made to act on the site | part adjacent to the mutually opposing direction and the direction which cross | intersects the opposing direction, The urging | biasing force with respect to the 2nd seal member of a body can be increased, and the sealing performance between a 2nd seal member and a 2nd valve member can be improved.

  Moreover, according to the evaporative fuel processing apparatus described in claim 7, the evaporation in which the solenoid valve according to any one of claims 1 to 6, the fuel tank and the canister are communicated and the solenoid valve is interposed. And a first passage portion of the electromagnetic valve is connected to the fuel tank side of the evaporated fuel passage, and a second passage portion of the electromagnetic valve is connected to the canister side. Accordingly, it is possible to provide an evaporative fuel processing apparatus provided with an electromagnetic valve that can improve the flow rate control accuracy and improve the sealing performance between the valve member and the valve seat while having a bidirectional relief function. Can do. Further, when the vaporized fuel is purged, the flow rate of the vaporized fuel flowing through the vaporized fuel passage is accurately controlled by the electromagnetic valve, so that the disturbance of the air-fuel ratio (A / F) can be suppressed.

It is a block diagram which shows the evaporative fuel processing apparatus concerning embodiment. It is sectional drawing which shows a flow control valve. It is sectional drawing which shows a valve mechanism part. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3. It is sectional drawing which shows the valve opening state of a 1st valve member. It is sectional drawing which shows the valve opening state of a 2nd valve member. It is sectional drawing which shows the valve opening state of the 3rd valve member by the differential pressure of the internal pressure of a 1st channel | path part, and the internal pressure of a 2nd channel | path part. It is sectional drawing which shows the valve opening state of the 2nd valve member by the differential pressure of the internal pressure of a 1st channel | path part, and the internal pressure of a 2nd channel | path part. It is sectional drawing which shows the principal part of a valve mechanism part. It is sectional drawing which shows the principal part of the solenoid valve concerning a prior art example.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. For convenience of explanation, after describing the outline of the evaporated fuel processing apparatus of the engine (internal combustion engine), the flow control valve as an electromagnetic valve provided in the evaporated fuel processing apparatus will be described. FIG. 1 is a configuration diagram showing an evaporative fuel processing apparatus.
As shown in FIG. 1, the evaporated fuel processing device 12 is provided in an engine system 10 of a vehicle such as an automobile. The engine system 10 includes an engine 14 and a fuel tank 15 that stores fuel supplied to the engine 14. The fuel tank 15 is provided with an inlet pipe 16. The inlet pipe 16 is a pipe that introduces fuel into the fuel tank 15 from a fuel filler port at an upper end portion thereof. A tank cap 17 is detachably attached to the oil filler port of the inlet pipe 16. Further, the upper end portion of the inlet pipe 16 and the air layer portion in the fuel tank 15 are communicated with each other via a breather pipe 18.

  A fuel supply device 19 is provided in the fuel tank 15. The fuel supply device 19 includes a fuel pump 20 that sucks in and pressurizes fuel in the fuel tank 15, a sender gauge 21 that detects the liquid level of the fuel, and a tank internal pressure sensor that detects a tank internal pressure as a relative pressure to the atmospheric pressure. 22 etc. The fuel pumped up from the fuel tank 15 by the fuel pump 20 is supplied to the delivery pipe 26 of the engine 14 through the fuel supply passage 24, and then injected from the injector (fuel injection valve) 25 into the intake passage 27. . In the intake passage 27, an air cleaner 28, an air flow meter 29, a throttle valve 30 and the like are provided.

  The fuel vapor processing apparatus 12 includes a fuel vapor passage 31, a purge passage 32, and a canister 34. One end portion (upstream end portion) of the evaporated fuel passage 31 is communicated with an air layer portion in the fuel tank 15. The other end (downstream end) of the evaporated fuel passage 31 communicates with the inside of the canister 34. Further, one end (upstream end) of the purge passage 32 communicates with the inside of the canister 34. The other end portion (downstream end portion) of the purge passage 32 communicates with a passage portion on the downstream side of the throttle valve 30 in the intake passage 27. The canister 34 is loaded with activated carbon (not shown) as an adsorbent. The evaporated fuel in the fuel tank 15 is adsorbed by the adsorbent (activated carbon) in the canister 34 through the evaporated fuel passage 31. Further, a fuel cut-off valve 35 and an ORVR differential pressure valve (On Board Refueling Vapor Recovery valve) 36 are provided at the upstream end portion of the evaporated fuel passage 31 in the air layer portion in the fuel tank 15.

  A flow control valve 38 is interposed in the middle of the evaporated fuel passage 31. A purge control valve 40 is interposed in the purge passage 32. Further, an atmospheric passage 42 is communicated with the canister 34 via a switching valve 41. The other end of the atmospheric passage 42 is open to the atmosphere. An air filter 43 is provided in the middle of the air passage 42. The flow control valve 38, the purge control valve 40, and the switching valve 41 are electromagnetic valves that are controlled to open and close by a drive signal output from an engine control device (hereinafter referred to as “ECU”) 45. The evaporative fuel passage 31 is divided into a passage portion 31a on the upstream side (fuel tank 15 side) and a passage portion 31b on the downstream side (canister 34 side), and a flow control valve 38 is provided between the passage portions 31a and 31b. Is intervening. The flow control valve 38 will be described in detail later.

  In addition to the tank internal pressure sensor 22, the flow rate control valve 38, the purge control valve 40, and the switching valve 41, the ECU 45 is connected to a lid switch 46, a lid opener 47, a display device 49, and the like. The lid opener 47 is connected to a lid manual opening / closing device (not shown) that manually opens and closes the lid 48 that covers the fuel filler opening. The lid opener 47 is a lock mechanism of the lid 48 and releases the lock of the lid 48 when a lid opening signal is supplied from the ECU 45 or when the lid manual opening / closing device is opened. Further, the lid switch 46 outputs a signal for unlocking the lid 48 to the ECU 45. The ECU 45 corresponds to “control means” in this specification.

Next, the basic operation of the fuel vapor processing apparatus 12 will be described.
(1) While the vehicle is parked While the vehicle is parked, the flow control valve 38 is kept closed. Therefore, the evaporated fuel in the fuel tank 15 does not flow into the canister 34. Further, the air in the canister 34 does not flow into the fuel tank 15. At this time, the purge control valve 40 and the switching valve 41 are also maintained in the closed state.

(2) During traveling of the vehicle During traveling of the vehicle, the ECU 45 performs control to purge the evaporated fuel adsorbed by the canister 34 when a predetermined purge condition is satisfied. In this control, the purge control valve 40 is controlled to open and close while the switching valve 41 is opened and the canister 34 is in communication with the atmosphere via the atmosphere passage 42. When the purge control valve 40 is opened, the intake negative pressure of the engine 14 acts in the canister 34 via the purge passage 32. As a result, the evaporated fuel in the canister 34 is introduced into the intake passage 27 together with the air sucked from the atmospheric passage 42 and burned in the engine 14. The ECU 45 opens the flow control valve 38 only during the purge of the evaporated fuel. Thereby, the tank internal pressure of the fuel tank 15 is maintained at a value near atmospheric pressure.

(3) During refueling When the lid switch 46 is operated while the vehicle is stopped, the ECU 45 opens the flow control valve 38. At this time, if the tank internal pressure of the fuel tank 15 is higher than the atmospheric pressure, the flow rate control valve 38 opens, and at the same time, the evaporated fuel in the fuel tank 15 passes through the evaporated fuel passage 31 and the adsorbent in the canister 34. To be adsorbed. This prevents the evaporated fuel from being released into the atmosphere. As a result, the tank internal pressure of the fuel tank 15 decreases to a value near atmospheric pressure. Further, when the tank internal pressure of the fuel tank 15 decreases to a value near atmospheric pressure, the ECU 45 outputs a signal for releasing the lock of the lid 48 to the lid opener 47. Upon receiving the signal, the lid opener 47 releases the lock of the lid 48, so that the lid 48 can be opened. Then, in a state where the lid 48 is opened and the tank cap 17 is opened, the fuel supply to the fuel tank 15 is started. In addition, since the tank cap 17 is opened after the tank internal pressure of the fuel tank 15 is lowered to a value close to the atmospheric pressure, the evaporated fuel is prevented from being released into the atmosphere from the fuel filler port. Further, the ECU 45 keeps the flow control valve 38 in an open state until the end of refueling (specifically, the lid 48 is closed). For this reason, during refueling, the evaporated fuel in the fuel tank 15 passes through the evaporated fuel passage 31 and is adsorbed by the adsorbent in the canister 34.

Next, the flow control valve 38 will be described. 2 is a cross-sectional view showing the flow control valve, FIG. 3 is a cross-sectional view showing the valve mechanism, FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG. 3, and FIG. FIG. 6 is a cross-sectional view showing a valve opening state of the second valve member, and FIG. 7 shows a valve opening state of the third valve member due to a differential pressure between the internal pressure of the first passage portion and the internal pressure of the second passage portion. FIG. 8 is a cross-sectional view showing the valve-opening state of the second valve member, and FIG. 9 is a cross-sectional view showing the main part of the valve mechanism. In this specification, the left, right, up and down directions of the flow control valve 38 are determined based on the cross-sectional view of FIG.
As shown in FIG. 2, the flow control valve 38 includes a valve mechanism 51 and a step motor 53 that drives the valve mechanism 51. For the convenience of explanation, the valve mechanism 51 will be explained after explaining the step motor 53.

  The step motor 53 is also called a stepper motor, a stepping motor or the like, and includes a motor housing 54 having an opening on the lower surface. The lower surface opening portion of the motor housing 54 is closed by a connecting housing 55 having a cylindrical shape. The motor housing 54 and the connecting housing 55 are connected concentrically. A stator 59 is provided in the motor housing 54 by winding an exciting coil 58 around a bobbin 57. A hollow cylindrical rotor 61 that rotates in the stator 59 is supported in the motor housing 54 so as to be rotatable around a vertical axis at a predetermined height position. A permanent magnet is disposed on the outer periphery of the rotor 61. A nut member 62 is concentrically integrated in the upper portion of the rotor 61. An upper end portion of the nut member 62 is rotatably supported with respect to the motor housing 54 via a bearing 63. A cylindrical bearing stand 64 is concentrically fixed on the upper wall portion 55a of the connection housing 55. A lower end portion of the rotor 61 is rotatably supported on the upper portion of the bearing base 64 via a bearing 65.

  In the female screw hole (reference numeral omitted) of the nut member 62, a male thread (reference numeral omitted) of the upper portion of the operating shaft 67 is screwed. The operating shaft 67 corresponds to the output shaft of the step motor 53. Further, the lower portion of the operating shaft 67 is supported so as to be movable in the axial direction, that is, in the vertical direction, while being prevented from rotating in the axial direction with respect to the inside of the bearing base 64. Therefore, the operating shaft 67 is reciprocated in the vertical direction by the forward / reverse rotation of the rotor 61. Further, the lower end portion of the operating shaft 67 passes through the upper wall portion 55 a of the connection housing 55. A disc-shaped operating plate 68 is formed concentrically at the lower end of the operating shaft 67. The step motor 53 is driven and controlled by the ECU 45 (see FIG. 1). The step motor 53 corresponds to an “electromagnetic drive unit” in this specification. The operation plate 68 corresponds to an “operation member” in this specification.

  Next, the valve mechanism 51 will be described. As shown in FIG. 3, the valve mechanism 51 includes a valve housing 70. The valve housing 70 is concentrically coupled to the lower end portion of the peripheral wall portion 55 b of the connection housing 55. The valve housing 70 includes an inner cylinder part 71, an outer cylinder part 72, an upper annular wall part 73, a lower annular wall part 74, a first connection pipe part 75, and a second connection pipe part 76. The inner cylinder portion 71 and the outer cylinder portion 72 are concentric with the connection housing 55 and have an inner and outer double cylindrical shape (see FIG. 4). The upper annular wall 73 closes the upper end surface of the annular space between the inner cylinder 71 and the outer cylinder 72. The lower annular wall 74 closes the lower end surface of the annular space between the inner cylinder 71 and the outer cylinder 72. In addition, the first connecting pipe portion 75 is connected to the right side portion of the outer cylinder portion 72. In addition, the second connecting pipe portion 76 is connected to the left side portion of the outer cylinder portion 72. Further, the outer peripheral end portion of the lid plate 78 is coupled to the lower surface of the lower annular wall portion 74. The lid plate 78 closes the lower surface opening of the inner cylinder portion 71. A valve chamber 82 is formed by the internal space 81 of the inner cylinder portion 71 and the internal space 80 of the connection housing 55.

  As shown in FIG. 4, the annular space part between the inner cylinder part 71 and the outer cylinder part 72 has a front partition wall 83a and a rear partition wall 83b installed between both (71, 72). Therefore, the space portion is divided into a left space portion 84 and a right space portion 85. Further, the first connecting pipe portion 75 serves as a first passage portion 87 communicating with the right space portion 85. The second connecting pipe portion 76 is a second passage portion 88 that communicates with the left space portion 84. Further, as shown in FIG. 3, a first opening hole that penetrates in the left-right direction and communicates the first passage portion 87 and the internal space 81 of the inner cylinder portion 71 at the lower end portion of the left side portion of the inner cylinder portion 71. 90 is formed. Further, a second opening hole 92 that penetrates in the vertical direction and communicates the internal space 80 of the connection housing 55 and the second space portion 84 is formed in the left side portion of the upper annular wall portion 73. The first passage portion 87, the first space portion 85, the first opening hole 90, the valve chamber 82, the second opening hole 92, the second space portion 84, and the second passage portion 88 are formed in a series. A fluid passage 94 is formed. For convenience of explanation, the internal space 81 is referred to as “the internal space 81 of the valve housing 70”. The right space 85 is referred to as a “first space 85”. The left space 84 is referred to as a “second space 84”.

As shown in FIG. 3, three valve members, that is, a first valve member 96, a second valve member 97, and a third valve member 98 are arranged in the valve chamber 82. Hereinafter, for convenience of explanation, the third valve member 98, the second valve member 97, and the first valve member 96 will be described in this order.
The third valve member 98 will be described. The third valve member 98 is formed in an annular plate shape. An outer peripheral portion of the third valve member 98 is a third valve portion 98 a corresponding to a third valve seat 100 (described later) of the valve housing 70. Further, the inner peripheral portion of the third valve member 98 is a second valve seat 98b corresponding to a second valve portion 97a (described later) of the second valve member 97. That is, the third valve portion 98a and the second valve seat 98b are formed in a common plate-like portion (referred to as “valve plate portion”). Further, a cylindrical peripheral wall portion 98 c is integrally formed concentrically on the upper surface of the outer peripheral edge of the valve plate portion of the third valve member 98.

  The third valve member 98 is loosely arranged in the peripheral wall portion 55b of the connection housing 55 via a predetermined gap. An annular gap between the peripheral wall portion 98 c of the third valve member 98 and the peripheral wall portion 55 b of the connection housing 55 is a third flow passage 105. The third flow passage 105 corresponds to a flow passage that communicates the internal space 80 of the connection housing 55 in the vertical direction (axial direction).

  A third valve seat 100 protruding inward in the radial direction is integrally formed on the inner peripheral portion of the annular wall portion 73 on the upper side of the valve housing 70. The third valve seat 100 is formed in an annular plate shape that is continuous with the upper annular wall portion 73. Further, the third valve seat 100 is configured such that the third valve portion 98a of the third valve member 98 can be seated and separated. Further, when the third valve member 98 is opened, that is, when the third valve portion 98a is separated from the third valve seat 100, the third communication passage 101 between the third valve seat 100 and the third valve portion 98a is formed. Open (see FIG. 7). That is, the third communication passage 101 is a communication passage that communicates between the third valve seat 100 and the third valve portion 98a in the radial direction, and is opened and closed by the third valve member 98. Further, when the third valve member 98 is opened, the second valve member 97 is restricted from moving upward from the position shown in FIG. 7 by a stopper means (not shown).

  As shown in FIG. 3, a third spring 103 made of a coil spring is interposed between opposing surfaces in the axial direction (vertical direction) between the third valve member 98 and the upper wall portion 55 a of the connection housing 55. ing. The third spring 103 always urges the third valve member 98 downward, that is, in the valve closing direction. The third spring 103 corresponds to “third urging means” in this specification.

  The second valve member 97 will be described. The second valve member 97 is formed in an annular plate shape having a smaller diameter than the third valve member 98. The outer peripheral portion of the second valve member 97 is a second valve portion 97 a corresponding to the second valve seat 98 b of the third valve member 98. Further, the inner peripheral portion of the second valve member 97 is a first valve seat 97 b corresponding to a first valve portion 96 a (described later) of the first valve member 97. That is, the second valve portion 97a and the first valve seat 97b are formed in a common plate-like portion (referred to as “valve plate portion”). Further, a hollow interlocking shaft portion 97 c is integrally formed concentrically on the upper surface of the inner peripheral edge of the valve plate portion of the second valve member 97. A cylindrical peripheral wall portion 97d is integrally formed concentrically on the lower surface of the outer peripheral edge of the valve plate portion of the second valve member 97. Further, a cylindrical wall portion 97e having a double cylindrical shape with respect to the inside of the peripheral wall portion 97d is integrally formed on the lower surface of the second valve member 97 concentrically.

  The second valve member 97 is arranged loosely with a predetermined gap in the hollow portion of the third valve seat 100 of the valve housing 70. The second valve portion 97 a of the second valve member 97 can be seated and separated from the second valve seat 98 b of the third valve member 98. Further, the interlocking shaft portion 97 c of the second valve member 97 is disposed at the center of the hollow portion of the third valve member 98. An annular gap between the peripheral wall portion 97 d of the second valve member 97 and the third valve seat 100 of the valve housing 70 is a second flow passage 109. The second flow passage 109 corresponds to a flow passage that communicates the internal space 81 of the valve housing 70 in the vertical direction (axial direction).

  When the second valve member 97 is opened, that is, when the second valve member 97a is separated from the second valve seat 98b of the third valve member 98, the second valve member 98b is interposed between the second valve member 98b and the second valve member 97a. The second communication path 110 is opened (see FIG. 6). That is, the second communication passage 110 is a communication passage that communicates between the second valve seat 98b and the second valve portion 97a in the radial direction, and is opened and closed by the second valve member 97. Further, when the second valve member 97 is opened, the valve plate portion of the second valve member 97 moves below the third valve seat 100. Therefore, the internal space 81 of the valve housing 70 and the internal space 80 of the connection housing 55 are communicated with each other via the second communication passage 110.

  As shown in FIG. 3, a second spring 112 made of a coil spring is interposed between the opposing surfaces of the second valve member 97 and the cover plate 78 in the axial direction (vertical direction). The second spring 112 always urges the second valve member 97 upward, that is, in the valve closing direction. The upper end portion of the second spring 112 is fitted into an annular space portion between the peripheral wall portion 97d of the second valve member 97 and the cylindrical wall portion 97e. The second spring 112 corresponds to “second urging means” in this specification.

  The first valve member 96 will be described. The first valve member 96 is formed in a disk shape having a smaller diameter than the second valve member 97. An outer peripheral portion of the first valve member 96 is a first valve portion 96 a corresponding to the first valve seat 97 b of the second valve member 97. The plate-like portion including the first valve portion 96a is referred to as “valve plate portion”. Further, a solid interlocking shaft portion 96 b is integrally formed concentrically on the upper surface of the central portion of the valve plate portion of the first valve member 96. Further, a cylindrical peripheral wall portion 96c is integrally formed concentrically on the lower surface of the outer peripheral edge of the valve plate portion of the first valve member 96.

  The first valve member 96 is disposed on the lower side of the second valve member 97. The first valve portion 96 a of the first valve member 96 can be seated and separated from the first valve seat 97 b of the second valve member 97. Further, the interlocking shaft portion 96b of the first valve member 96 is disposed loosely in the interlocking shaft portion 97c of the second valve member 97 through a predetermined gap. An annular gap between the interlocking shaft portions 96b and 97c is a first flow passage (referred to as an “upper first flow passage”) 114. The upper first flow passage 114 corresponds to a flow passage communicating between the interlocking shaft portions 96b and 97c in the vertical direction (axial direction). Further, the peripheral wall portion 96c of the first valve member 96 is disposed in a loosely fitted manner with a predetermined gap with respect to the cylindrical wall portion 97e of the second valve member 97. An annular gap between the peripheral wall portion 96 c and the cylindrical wall portion 97 e is a first flow passage (referred to as a “lower first flow passage”) 115. The lower first flow passage 115 corresponds to a flow passage communicating in the vertical direction (axial direction) between the peripheral wall portion 96c and the cylindrical wall portion 97e.

  When the first valve member 96 is opened, that is, when the first valve portion 96a is separated from the first valve seat 97b of the second valve member 97, the first valve member 96b is located between the first valve seat 97b and the first valve portion 96a. The first communication passage 116 is opened (see FIG. 5). That is, the first communication passage 116 is a communication passage that communicates between the first valve seat 97b and the first valve portion 96a in the radial direction, and is opened and closed by the first valve member 96. The first communication passage 116 is communicated with the internal space 81 of the valve housing 70 via the lower first flow passage 115, and the connection housing 55 is connected via the upper first flow passage 114. It communicates with the internal space 80. Thereby, the internal space 81 of the valve housing 70 and the internal space 80 of the connection housing 55 are communicated.

  As shown in FIG. 3, a first spring 118 made of a coil spring is interposed between the axial surfaces (vertical directions) of the first valve portion 96 a of the first valve member 96 and the lid plate 78. Has been. The first spring 118 always urges the first valve member 96 upward, that is, in the valve closing direction. The first spring 118 is disposed so as to form a double ring shape with respect to the second spring 112 (see FIG. 4). The first spring 118 corresponds to the “first urging means” in this specification.

  As shown in FIG. 3, when the first valve member 96 and the second valve member 97 are closed, the upper end portion of the interlocking shaft portion 96 b of the first valve member 96 is connected to the interlocking shaft portion 97 c of the second valve member 97. It is set so as to protrude upward from the upper end surface. Therefore, the interval of the interlocking shaft portion 96b of the first valve member 96 with respect to the operating plate 68 of the step motor 53 (see FIG. 2) is also smaller than the interval of the interlocking shaft portion 97c of the second valve member 97. The operating plate 68 is formed with an outer diameter larger than the outer diameter of the interlocking shaft portion 97c of the second valve member 97 and smaller than the inner diameter of the third valve member 98.

  On the upper surface of the first valve portion 96a of the first valve member 96, an annular first seal member 120 made of a rubber-like elastic body is mounted concentrically and by adhesion or the like. The first seal member 120 is formed in a square cross section. The first seal member 120 corresponds to the first valve seat 97 b of the second valve member 97. Therefore, when the first valve member 96 is closed, the space between the first valve seat 97b of the second valve member 97 and the first valve portion 96a of the first valve member 96 is elastic through the first seal member 120. Sealed. Further, when the first valve member 96 is opened, the first seal member 120 is separated from the first valve seat 97b of the second valve member 97 (see FIG. 5).

  The first seal member 120 and the first spring 118 are arranged with a positional relationship corresponding to the axial direction, that is, the vertical direction (see FIG. 9). That is, the center diameter of the first seal member 120 and the coil diameter of the first spring 118 (the center diameter of the coil portion) are set to the same or approximate size. The first seal member 120 can be attached to the first valve seat 97b instead of the first valve portion 96a.

  An annular seal body 122 made of a rubber-like elastic body is concentrically attached to the lower surface of the third valve member 98 by adhesion or the like. The seal body 122 includes an annular plate-shaped substrate portion 122a, and an inner ring-side seal projection 122b and an outer ring-side seal projection 122c that project in a double annular shape on the lower surface side of the substrate portion 122a. The substrate portion 122a is formed in a horizontally long cross-sectional shape. Both seal protrusions 122b and 122c are formed in a semicircular cross section. The inner ring side seal protrusion 122 b corresponds to the second valve portion 97 a of the second valve member 97. Further, the outer ring side seal projection 122 c corresponds to the third valve seat 100 of the valve housing 70. The third valve member 98 corresponds to a valve member to which the seal body 122 is attached.

  When the second valve member 97 is closed, the space between the second valve seat 98b of the third valve member 98 and the second valve portion 97a of the second valve member 97 is elastic through the inner ring side seal protrusion 122b. Sealed. Further, when the second valve member 97 is opened, the second valve portion 97a of the second valve member 97 is separated from the inner ring side seal protrusion 122b (see FIG. 6). The inner ring side seal protrusion 122b corresponds to “inner ring side seal member” and “second seal member” in this specification.

  When the third valve member 98 is closed, the space between the third valve seat 100 of the valve housing 70 and the third valve portion 98a of the third valve member 98 is elastically sealed through the outer ring side seal protrusion 122c. (See FIG. 9). Further, when the third valve member 98 is opened, the outer ring side seal protrusion 122c is separated from the third valve seat 100 of the valve housing 70 (see FIG. 7). The outer ring side seal protrusion 122c corresponds to “outer ring side seal member” and “third seal member” in this specification.

  The inner ring side seal protrusion 122b and the second spring 112 are arranged with a positional relationship corresponding to the axial direction, that is, the vertical direction (see FIG. 9). That is, the center diameter of the inner ring-side seal protrusion 122b and the coil diameter of the second spring 112 (center diameter of the coil portion) are set to the same or approximate size.

  The outer ring side seal projection 122c and the third spring 103 are arranged with a positional relationship corresponding to the axial direction, that is, the vertical direction (see FIG. 9). Further, the third spring 103 is arranged so that the urging force acts on an intermediate portion between the inner ring side seal projection 122 b and the outer ring side seal projection 122 c of the seal body 122. That is, the intermediate diameter between the center diameter of the inner ring side seal protrusion 122b and the center diameter of the outer ring side seal protrusion 122c and the coil diameter of the third spring 103 (center diameter of the coil portion) are equal or approximate. The size is set. Accordingly, the second spring 112 that urges the second valve member 97 and the third spring 103 that urges the third valve member 98 have a biasing force in the opposite direction and in the opposite direction. It arrange | positions so that it may act on the site | part adjacent to the direction (coil radial direction) which cross | intersects.

  The valve housing 70, the first valve member 96, the second valve member 97, and the third valve member 98 are each formed of a resin molded product formed by resin molding. Further, as shown in FIG. 9, the valve plate portion including the second valve portion 97a and the first valve seat 97b of the second valve member 97 is formed in a thin plate shape. That is, the valve plate portion of the second valve member 97 is formed in a thin plate shape in the contact / separation direction (axial direction, vertical direction) of the inner ring side seal protrusion 122b and the first seal member 120. The second valve portion 97a corresponds to a contact portion to which the inner ring side seal projection 122b of the seal body 122 is brought into contact with and separated from. The first valve seat 97b corresponds to an abutting portion where the first seal member 120 is contacted and separated. The contact / separation direction of the inner ring side seal protrusion 122b and the first seal member 120 corresponds to the opening / closing direction of the second valve member 97.

  The third valve seat 100 of the valve housing 70 is formed in a thin plate shape. That is, the third valve seat 100 is formed in a thin plate shape in the contact / separation direction (axial direction, vertical direction) of the outer ring side seal projection 122c. The third valve seat 100 corresponds to an abutting portion to which the outer ring side seal projection 122c of the seal body 122 is contacted and separated. The contact / separation direction of the outer ring side seal projection 122c corresponds to the opening / closing direction of the third valve member 98.

  In the present embodiment, the valve plate portion including the first valve portion 96a of the first valve member 96 is formed in a thin plate shape. That is, the valve plate portion of the first valve member 96 is formed in a thin plate shape in the opening / closing direction (axial direction, vertical direction) of the first valve member 96. The first valve portion 96a corresponds to a mounting portion on which the first seal member 120 is mounted.

  The valve plate portion including the third valve portion 98a and the second valve seat 98b of the third valve member 98 is formed in a thin plate shape. That is, the valve plate portion of the third valve member 98 is formed in a thin plate shape in the opening / closing direction (axial direction, vertical direction) of the third valve member 98. The third valve portion 98a and the second valve seat 98b correspond to a mounting portion to which the seal body 122 is mounted.

  The flow rate control valve 38 is formed between the downstream end portion of the upstream side (fuel tank 15 side) passage portion 31a and the downstream side (canister 34 side) passage portion 31b of the evaporated fuel passage 31 in the evaporated fuel processing device 12. (See FIG. 1). That is, the downstream end portion of the upstream passage portion 31 a communicates with the first passage portion 87 of the valve housing 70, and the upstream end portion of the downstream (canister 34 side) passage portion 31 b is the valve housing 70. The second passage portion 88 is communicated. The valve housing 70 is attached to a stationary member (not shown) on the vehicle body side with a bolt or the like.

Next, the operation of the flow control valve 38 will be described.
(1) Closed state of all valve members 96, 97, 98 While the vehicle is parked, the first valve member 96, the second valve member 97, and the third valve member in the valve mechanism 51 of the flow control valve 38. 98 is kept closed (see FIGS. 2 and 3). That is, the first valve member 96 is maintained in a closed state by the urging force of the first spring 118. Further, the second valve member 97 is maintained in a closed state by the urging force of the second spring 112. Further, the third valve member 98 is maintained in the closed state by the urging force of the third spring 103 with the direction opposite to the closing direction of the first valve member 96 as the closing direction. Further, the operating shaft 67 of the step motor 53 is in the retracted position (upward position), and the operating plate 68 of the operating shaft 67 is connected to the interlocking shaft portion 96b of the first valve member 96 and the interlocking shaft portion 97c of the second valve member 97. It is in the position away from. Therefore, in the evaporated fuel processing apparatus 12 (see FIG. 1), the evaporated fuel in the fuel tank 15 does not flow into the canister 34 via the evaporated fuel passage 31, and conversely, the air in the canister 34 There is no flow into the fuel tank 15 via the evaporated fuel passage 31. When all the valve members 96, 97, 98 are closed, the internal pressure (pressure on the fuel tank 15 side) P1 of the first passage portion 87 is larger than the internal pressure (pressure on the canister 34 side) P2 of the second passage portion 88. The relief function of the flow rate control valve 38 when it becomes larger than the predetermined value or smaller than the predetermined value will be described later.

(2) Opening state of the first valve member 96 (the other valve members 97 and 98 are closed)
When a small flow rate of evaporated fuel is allowed to flow from the fuel tank 15 side to the canister 34 side through the evaporated fuel passage 31 (see FIG. 1) while the vehicle is traveling, the ECU 45 sends the first flow to the step motor 53 of the flow rate control valve 38. The valve opening signal at the stage is input, and the rotor 61 is rotated in the valve opening direction. Then, the operating shaft 67 is moved from the retracted position (upward position) to the first-stage advance position (downward movement position) (see FIG. 5). Accordingly, the operating plate 68 of the operating shaft 67 contacts the interlocking shaft portion 96 b of the first valve member 96 and pushes down the first valve member 96 against the bias of the first spring 118. As a result, the first valve member 96 is opened, so that the internal space 81 of the valve housing 70 and the internal space 80 of the connection housing 55 communicate with each other. Specifically, when the first communication passage 116 is opened, a lower first flow passage 115 that communicates with the internal space 81 of the valve housing 70 and an upper first flow passage that communicates with the internal space 80 of the connection housing 55. 114 is communicated. At this time, the operating plate 68 of the operating shaft 67 is separated from the interlocking shaft portion 97c of the second valve member 97 with a predetermined gap. Further, the internal space 80 of the connection housing 55 is always in communication with the second passage portion 88 through the third flow passage 105, the second opening hole 92, and the second space portion 84.

  Accordingly, the evaporated fuel from the first passage portion 87 of the valve housing 70 is the first space portion 85, the first opening 90, the inner space 81 of the valve housing 70, the lower first flow passage 115, the first communication passage. 116, the upper first flow passage 114, the gap between the operating plate 68 and the interlocking shaft portion 97c of the second valve member 97, the internal space 80 of the connection housing 55, the third flow passage 105, the second opening hole 92, It flows to the 2nd channel | path part 88 through the 2nd space part 84 (refer arrow in FIG. 5). The flow rate of the evaporated fuel at this time is a flow rate corresponding to the minimum passage cross-sectional area in a series of passages formed between the first valve member 96 and the second valve member 97.

(3) Opened state of the first valve member 96 and the second valve member 97 (the third valve member 98 is closed)
When a large flow of evaporated fuel is allowed to flow from the fuel tank 15 side to the canister 34 side through the evaporated fuel passage 31 (see FIG. 1) while the vehicle is traveling or refueling, the ECU 45 Is input to the step motor 53 of the flow control valve 38 from the second stage, and the rotor 61 is rotated in the valve opening direction. Then, the operating shaft 67 is moved from the first-stage advance position to the second-stage advance position (downward movement position) below (see FIG. 6). Accordingly, the operating plate 68 of the operating shaft 67 is in contact with the interlocking shaft portion 97c of the second valve member 97 while being in contact with the interlocking shaft portion 96b of the first valve member 96. The springs 118 and 112 are pushed down against the urging force. As a result, the second valve member 97 is opened, so that the internal space 81 of the valve housing 70 and the internal space 80 of the connection housing 55 communicate with each other. Specifically, when the second communication passage 110 is opened, the second flow passage 109 communicating with the internal space 81 of the valve housing 70 and the internal space 80 of the connection housing 55 are communicated.

  Therefore, the evaporated fuel from the first passage portion 87 of the valve housing 70 is connected to the first space portion 85, the first opening 90, the internal space 81 of the valve housing 70, the second flow passage 109, the second communication passage 110, and the connection. It flows to the second passage portion 88 through the internal space 80 of the housing 55, the third flow passage 105, the second opening hole 92, and the second space portion 84 (see arrows in FIG. 6). The flow rate of the evaporated fuel at this time is a flow rate corresponding to the minimum passage cross-sectional area in a series of passages formed between the second valve member 97 and the third valve member 98.

In addition, the minimum passage cross-sectional area in a series of passages formed between the first valve member 96 and the second valve member 97 by opening the first valve member 96 is A, and the second valve member 97 is opened. When the minimum passage sectional area in the series of passages formed between the second valve member 97 and the third valve member 98 by the valve is B, the passage sectional area A and the passage sectional area B are:
A <B
It is set to satisfy the relationship. Therefore, the small flow rate can be controlled by opening the first valve member 96, and the large flow rate more than twice the small flow rate can be controlled by opening the second valve member 97.

  Further, in a valve open state (see FIG. 6) of both valve members 96 and 97, a valve closing signal is input from the ECU 45 (see FIG. 1) to the step motor 53 of the flow control valve 38, and the rotor 61 is closed (see FIG. 6). When rotated in the direction opposite to the valve opening direction), the operating shaft 67 is retracted (moved upward), so that the second valve member 97 is closed by the urging force of the second spring 112 (see FIG. 5). The first valve member 96 is closed by the biasing force of the first spring 118 (see FIGS. 2 and 3).

(4) When all the valve members 96, 97, 98 are closed, the internal pressure (pressure on the fuel tank 15 side) P1 of the first passage portion 87 becomes the internal pressure (pressure on the canister 34 side) P2 of the second passage portion 88. When the pressure is larger than a predetermined value, the internal pressure P1 of the first passage portion 87 is set to the second passage portion in the closed state of all the valve members 96, 97, 98, that is, when the vehicle is parked (see FIGS. 2 and 3). A case where the pressure becomes greater than the predetermined value Pα as compared with the internal pressure P2 of 88 will be described. In this case, the relationship between the differential pressure Pa obtained by subtracting the internal pressure P2 from the internal pressure P1 and the predetermined value Pα is:
Pa = P1-P2
Pα <Pa
It is represented by

  In this case, the third valve member 98 is opened against the urging force of the third spring 103 by the differential pressure Pa equal to or greater than the predetermined value Pα (see FIG. 7). Thereby, the 3rd communication path 101 is opened, and the 2nd flow path 109 and the 2nd opening hole 92 are connected. Therefore, when the internal pressure P1 is released to the second passage portion 88, the differential pressure Pa between the internal pressure P1 and the internal pressure P2 can be controlled to be equal to or less than the predetermined value Pα. That is, the third valve member 98 functions as a positive-direction relief valve that opens when the internal pressure P1 is greater than the internal pressure P2 by a predetermined value Pα or more. If the differential pressure Pa is equal to or less than the predetermined value Pα, the third valve member 98 is closed by the urging force of the third spring 103 (see FIG. 3).

(5) When all the valve members 96, 97, 98 are closed, the internal pressure (pressure on the fuel tank 15 side) P1 of the first passage portion 87 becomes the internal pressure (pressure on the canister 34 side) P2 of the second passage portion 88. In the case where all the valve members 96, 97, 98 are closed, that is, when the vehicle is parked (see FIGS. 2 and 3), the internal pressure P1 of the first passage portion 87 is the second passage portion. A case where the pressure becomes smaller than the predetermined value Pβ as compared with the internal pressure P2 of 88 will be described. In this case, the relationship between the differential pressure Pb obtained by subtracting the internal pressure P1 from the internal pressure P2 and the predetermined value Pβ is:
Pb = P2-P1
Pβ <Pb
It is represented by

  In this case, the second valve member 97 is opened against the urging force of the second spring 112 by the differential pressure Pb equal to or greater than the predetermined value Pβ (see FIG. 8). As the second valve member 97 is opened, the first valve member 96 is pushed down against the urging force of the first spring 118. By opening the second valve member 97, the internal space 80 of the connection housing 55 and the internal space 81 of the valve housing 70 are communicated with each other. Specifically, when the second communication passage 110 is opened, the second flow passage 109 communicating with the internal space 81 of the valve housing 70 and the internal space 80 of the connection housing 55 are communicated. Therefore, when the internal pressure P2 is released to the first passage portion 87, the differential pressure Pb between the internal pressure P1 and the internal pressure P2 can be controlled to be equal to or less than the predetermined value Pβ. That is, the second valve member 97 functions as a reverse relief valve that opens when the internal pressure P1 is smaller than the internal pressure P2 by a predetermined value Pβ or more. If the differential pressure Pb becomes equal to or less than the predetermined value Pβ, the second valve member 97 is closed by the urging force of the second spring 112 and the first valve member 96 is pushed up by the urging force of the first spring 118. (See FIG. 3).

  According to the flow control valve 38 described above, when the internal pressure P1 of the first passage portion 87 becomes larger than the internal pressure P2 of the second passage portion 88 by a predetermined value or more, the third valve member 98 of the third spring 103 By opening the valve against the urging force, the differential pressure between the internal pressure P1 of the first passage portion 87 and the internal pressure P2 of the second passage portion 88 can be controlled to a predetermined value or less (see FIG. 7). When the internal pressure P1 of the first passage portion 87 becomes smaller than the internal pressure P2 of the second passage portion 88 by a predetermined value or more, the second valve member 97 opens against the urging force of the second spring 112. By controlling the pressure, the differential pressure between the internal pressure P1 of the first passage portion 87 and the internal pressure P2 of the second passage portion 88 can be controlled to a predetermined value or less. Therefore, a bidirectional relief function can be provided. Although the second valve member 97 is configured to open when the internal pressure P1 of the first passage portion 87 is smaller than the internal pressure P2 of the second passage portion 88 by a predetermined value or more, the second valve member 97 is configured to open. Instead of this, the first valve member 96 may be opened, or the second valve member 96 and the second valve member 97 may be opened.

  Further, since the first valve member 96 and the second valve member 97 are opened stepwise by the operation plate 68 of the step motor 53, the flow rate is controlled as compared with the conventional solenoid valve (see Patent Document 1). Accuracy can be improved.

  Further, the valve member 96 is closed between the first valve portion 96a of the first valve member 96 and the first valve seat 97b of the second valve member 97 on which the first valve portion 96a can be seated and separated. In some cases, a first seal member 120 that elastically seals between the two (96a, 97b) is provided, and a first spring 118 that biases the first seal member 120 and the first valve member 96 corresponding to the seal member 120 is provided. Are arranged with a positional relationship corresponding to the axial direction. For this reason, the biasing force of the first spring 118 is applied to the seal portion by the first seal member 120 between the first valve portion 96a and the first valve seat 97b with a positional relationship corresponding to the axial direction. The sealing performance between the first valve portion 96a and the first valve seat 97b can be improved. This is effective as the flow control valve 38 that requires high airtightness.

  Further, the valve member 97 is closed between the second valve portion 97a of the second valve member 97 and the second valve seat 98b of the third valve member 98 on which the second valve portion 97a can be seated and separated. The inner ring side seal projection 122b of the seal body 122 that elastically seals between the two (97a, 98b) is provided, and the inner ring side seal projection 122b and the second valve member 97 corresponding to the seal projection 122b are attached. The second spring 112 is arranged with a positional relationship corresponding to the axial direction. For this reason, the biasing force of the second spring 112 has a positional relationship corresponding to the axial direction with respect to the seal portion by the inner ring side seal projection 122b of the seal body 122 between the second valve portion 97a and the second valve seat 98b. As a result, the sealing performance between the second valve portion 97a and the second valve seat 98b can be improved. This is effective as the flow control valve 38 that requires high airtightness.

  Further, when the valve member 97 is closed between the third valve portion 98a of the third valve member 98 and the third valve seat 100 of the valve housing 70 in which the third valve portion 98a can be seated and separated. The outer ring side seal projection 122c of the seal body 122 that elastically seals between both (98a, 100) is provided, and the outer ring side seal projection 122c and the third valve member 98 corresponding to the seal projection 122c are urged. The third spring 103 is arranged with a positional relationship corresponding to the axial direction. For this reason, the biasing force of the third spring 103 has a positional relationship corresponding to the axial direction with respect to the seal portion by the outer ring side seal projection 122c of the seal body 122 between the third valve portion 98a and the third valve seat 100. As a result, the sealing performance between the third valve portion 98a and the third valve seat 100 can be improved. This is effective as the flow control valve 38 that requires high airtightness.

  Further, the valve plate portion including the first valve seat 97b of the second valve member 97 with which the first seal member 120 is contacted and separated is formed into a thin plate shape in the contact and separation direction of the seal member 120 by resin molding. . Therefore, it is possible to reduce the amount of molding shrinkage deformation caused by resin molding of the valve plate portion of the second valve member 97 with which the first seal member 120 is contacted and separated, thereby preventing the occurrence of sink marks. As a result, the flatness of the contact surface of the first valve seat 97b of the second valve member 97 with which the first seal member 120 abuts is improved, so that the space between the first seal member 120 and the first valve seat 97b is improved. Sealability can be improved.

  Further, the valve plate portion including the second valve portion 97a of the second valve member 97 to which the inner ring side seal projection 122b of the seal body 122 is contacted and separated is thinned in the contact and separation direction of the inner ring side seal projection 122b by resin molding. It is formed in a plate shape. Therefore, it is possible to reduce the amount of deformation due to resin molding of the valve plate portion of the second valve member 97 with which the inner ring side seal projection 122b of the seal body 122 is contacted and separated, thereby preventing the occurrence of sink marks. Accordingly, the flatness of the contact surface of the second valve portion 97a of the second valve member 97 with which the inner ring side seal protrusion 122b of the seal body 122 contacts is improved, and therefore the inner ring side seal protrusion 122b of the seal body 122 is improved. And the second valve portion 97a can be improved in sealing performance.

  Further, the third valve seat 100 of the valve housing 70 to which the outer ring side seal projection 122c of the seal body 122 is contacted and separated is formed in a thin plate shape in the contact and separation direction of the outer ring side seal projection 122c by resin molding. is there. Accordingly, it is possible to reduce the amount of deformation due to resin molding of the third valve seat 100 of the valve housing 70 to which the outer ring side seal projection 122c of the seal body 122 is contacted and separated, thereby preventing the occurrence of sink marks. As a result, the flatness of the contact surface of the third valve seat 100 of the valve housing 70 with which the outer ring side seal protrusion 122c of the seal body 122 contacts is improved, so that the outer ring side seal protrusion 122c of the seal body 122 and the The sealing property between the three valve seats 100 can be improved.

  Further, the inner ring side seal protrusion 122b to which the second valve portion 97a of the second valve member 97 is contacted / separated and the outer ring side seal protrusion 122c to which the third valve seat 100 of the valve housing 70 is contacted / separated are double-annular. The seal body 122 is integrally formed. Accordingly, since the inner ring side seal projection 122b and the outer ring side seal projection 122c are provided with the seal body 122 integrally formed in a double ring shape, the coaxiality of both the seal projections 122b and 122c is improved. The sealing performance between the seal protrusion 122b and the second valve portion 97a and between the outer ring side seal protrusion 122c and the third valve seat 100 can be improved.

  Further, the third spring 103 that urges the third valve member 98 to which the seal body 122 is attached has its urging force acting on an intermediate portion between the inner ring side seal projection 122b and the outer ring side seal projection 122c. Are arranged as follows. Therefore, since the urging force of the third spring 103 acting on both the seal protrusions 122b and 122c of the seal body 122 is equalized, the inner ring side seal protrusion 122b and the second valve portion 97a are arranged between the outer ring side and the outer ring side. The sealing performance between the seal protrusion 122c and the third valve seat 100 can be improved.

  An annular third valve seat 100 on which the third valve member 98 can be seated and separated is formed on the valve housing 70, and the second valve formed on the second valve member 97 is formed on the third valve member 98. An annular second valve seat 98b on which the portion 97a can be seated and separated and a third valve portion 98a that can be seated on and separated from the third valve seat 100 are formed on a common valve plate portion (plate-shaped portion). The seal body 122 is provided on the valve plate portion of the third valve member 98, and the inner ring side seal protrusion 122b of the seal body 122 is used as the second seal member to which the second valve portion 97a of the second valve member 97 is contacted and separated. In addition, the outer ring side seal projection 122c of the seal body 122 is a third seal member that is brought into contact with and separated from the third valve seat 100. Accordingly, the inner ring side seal projection 122b of the seal body 122 provided on the valve plate portion (plate-shaped portion) of the third valve member 98 is used as the second seal member, and the outer ring side seal projection 122c of the seal body 122 is used. By using the third seal member, the sealing performance between the second seal member (122b) and the second valve portion 97a of the second valve member 97 is improved, and the third seal member (122c) and the valve housing 70 are improved. The sealing performance with the third valve seat 100 can be improved. In addition, the contact part which both seal protrusions 122b and 122c contact can also be made into one member. Further, both the seal protrusions 122b and 122c can be independent seal members.

  Further, the second spring 112 that urges the second valve member 97 and the third spring 103 that urges the third valve member 98 are in a direction (diameter in which the urging forces of the second spring 112 and the third spring 103 intersect each other in the opposing direction. It is arranged to act on the part adjacent to (direction). Accordingly, the urging force of the second spring 112 and the urging force of the third spring 103 can be applied to the portions adjacent to each other in the opposite direction and in the direction crossing the opposite direction. The urging force against the seal protrusion 122 b can be increased, and the sealing performance between the inner ring side seal protrusion 122 b and the second valve portion 97 a of the second valve member 97 can be improved.

  Further, the valve plate portion including the first valve portion 96a of the first valve member 96, which is a mounting portion to which the first seal member 120 is attached by adhesion or the like, is formed into a thin plate shape by resin molding. Accordingly, it is possible to reduce the amount of molding shrinkage deformation due to resin molding of the valve plate portion of the first valve member 96 to which the first seal member 120 is attached, and to prevent the occurrence of sink marks. As a result, the flatness of the mounting surface of the first valve portion 96a of the first valve member 96 to which the first seal member 120 is mounted is improved, so that the mounting between the first seal member 120 and the first valve portion 96a is performed. Property (adhesiveness) can be improved.

  Further, the valve plate portion including the third valve portion 98a and the second valve seat 98b of the third valve member 98, which is a mounting portion to which the seal body 122 is mounted by adhesion or the like, is formed into a thin plate shape by resin molding. . Therefore, it is possible to reduce the amount of molding shrinkage due to resin molding of the valve plate portion of the third valve member 98 to which the seal body 122 is attached, thereby preventing the occurrence of sink marks. As a result, the flatness of the mounting surfaces of the third valve portion 98a and the second valve seat 98b of the third valve member 98 to which the seal body 122 is mounted is improved, so that the seal body 122, the third valve portion 98a, and the second The mounting property (adhesiveness) with the valve seat 98b can be improved.

  Further, according to the evaporated fuel processing device 12 described above, the flow rate control valve 38 (see FIG. 2), the evaporated fuel passage 31 that communicates the fuel tank 15 and the canister 34 and is provided with the flow rate control valve 38 are provided. The first passage portion 87 of the flow control valve 38 is connected to the fuel tank 15 side of the evaporated fuel passage 31 and the second passage portion 88 of the flow control valve 38 is connected to the canister 34 side. Therefore, while providing the bidirectional relief function, the flow rate control accuracy is improved, and the sealing performance between the valve portions 96a, 97a, 98a of the valve members 96, 97, 98 and the valve seats 97b, 98b, 100 is provided. It is possible to provide the evaporated fuel processing apparatus 12 including the flow rate control valve 38 (see FIG. 2) that can improve the fuel efficiency. Further, when the evaporated fuel is purged, the flow rate of the evaporated fuel flowing through the evaporated fuel passage 31 is accurately controlled by the flow rate control valve (solenoid valve) 38, so that the disturbance of the air-fuel ratio (A / F) can be suppressed. .

  The present invention is not limited to the above embodiment, and can be modified without departing from the gist of the present invention. For example, the solenoid valve of the present invention is not limited to the flow rate control valve 38 of the evaporative fuel processing device 12 and can be applied to any application. Moreover, in the said embodiment, although each sealing member was provided between each valve member and the valve seat corresponding to this valve member, it is provided between at least one valve member and the valve seat corresponding to this valve member. What is necessary is just to arrange | position the sealing member and to arrange | position the sealing member and the biasing means which biases the valve member corresponding to the sealing member with the positional relationship corresponding to an axial direction. Further, instead of the seal body 122 having the second seal member (inner ring side seal protrusion 122b) and the third seal member (outer ring side seal protrusion 122c), independent second seal members and third seal members are used. Can be used. Further, the seal body 122 can also be used as a first seal member having both seal projections 122b and 122c corresponding to the first valve seat 97b of the second valve member 97. Further, the valve housing 70, the first valve member 96, the second valve member 97, and the third valve member 98 are not limited to resin molded products but may be metal products. In the case of a metal product, the contact portion of the valve member or the valve seat to which the seal member is contacted / separated may be formed in a thin plate shape in the contact / separation direction of the seal material by resin molding.

DESCRIPTION OF SYMBOLS 12 ... Evaporative fuel processing apparatus 15 ... Fuel tank 31 ... Evaporative fuel passage 34 ... Canister 38 ... Flow control valve (solenoid valve)
53 ... Step motor (electromagnetic drive unit)
68 ... Actuating plate (actuating member)
DESCRIPTION OF SYMBOLS 70 ... Valve housing 87 ... 1st channel | path part 88 ... 2nd channel | path part 94 ... Fluid path 96 ... 1st valve member 96a ... 1st valve part 97 ... 2nd valve member 97a ... 2nd valve part 97b ... 2nd valve seat 98 ... 3rd valve member 98a ... 3rd valve part 98b ... 2nd valve seat 100 ... 3rd valve seat 103 ... 3rd spring (3rd biasing means)
112 ... Second spring (second urging means)
118 ... 1st spring (1st biasing means)
DESCRIPTION OF SYMBOLS 120 ... 1st seal member 122 ... Seal body 122a ... Substrate part 122b ... Inner ring side seal protrusion (inner ring side seal member)
122c ... Outer ring side seal projection (outer ring side seal member)

Claims (7)

A valve housing forming a fluid passage having a first passage portion and a second passage portion communicating with each other;
A first valve member that opens and closes the fluid passage and is biased by a biasing force of a first biasing means with a direction along a fluid flow direction from the first passage portion to the second passage portion as a closing direction;
A second valve member that opens and closes the fluid passage and is biased by the biasing force of the second biasing means as a closing direction in the same direction as the closing direction of the first valve member;
An electromagnetic drive unit having an actuating member for gradually opening the first valve member and the second valve member;
A third valve member that opens and closes the fluid passage and is urged by a urging force of a third urging means with a closing direction opposite to the closing direction of the first valve member;
When the internal pressure of the first passage portion becomes greater than a predetermined value compared to the internal pressure of the second passage portion, the third valve member is opened against the urging force of the third urging means. And
When the internal pressure of the first passage portion becomes smaller than the internal pressure of the second passage portion by a predetermined value or more, at least one valve member of the first valve member and the second valve member is the urging means. It is configured to open against the urging force of
When the valve member is closed between at least one of the first valve member, the second valve member, and the third valve member and a valve seat on which the valve member can be seated and separated. A sealing member that elastically seals between the two is provided,
An electromagnetic valve characterized in that the sealing member and a biasing means for biasing a valve member corresponding to the seal member are arranged with a positional relationship corresponding to the axial direction. The electromagnetic valve according to claim 1,
An electromagnetic valve characterized in that a contact portion of the valve member or the valve seat to which the seal member is contacted / separated is formed in a thin plate shape in the contact / separation direction of the seal material by resin molding. The electromagnetic valve according to claim 1 or 2,
An electromagnetic valve comprising: a seal body in which an inner ring side seal member and an outer ring side seal member to which a contact portion of the valve member or the valve seat comes into contact are separated from each other. The electromagnetic valve according to claim 3,
The urging means for urging the valve member to which the seal body is mounted is arranged so that the urging force acts on an intermediate portion between the inner ring side seal member and the outer ring side seal member. A solenoid valve characterized by that. The solenoid valve according to claim 3 or 4,
An annular third valve seat on which the third valve member can be seated and separated is formed in the valve housing,
An annular second valve seat on which the second valve portion formed on the second valve member can be seated and separated from the third valve member, and a third that can be seated on and separated from the third valve seat. The valve part is formed in a common plate-like part,
The sealing body is provided on the plate-like portion of the third valve member,
The inner ring side seal member of the seal body is a second seal member to which the second valve portion of the second valve member is contacted and separated, and the outer ring side seal member of the seal body is contacted and separated from the third valve seat. A solenoid valve characterized by being a third seal member. The electromagnetic valve according to claim 5,
The second urging means for urging the second valve member and the urging means for urging the third valve member are adjacent to each other in the direction in which the urging forces cross each other in the opposing direction. An electromagnetic valve characterized by being arranged to act on the. A solenoid valve according to any one of claims 1 to 6, an evaporative fuel passage through which a fuel tank and a canister are communicated and in which the solenoid valve is interposed, and the first passage portion of the solenoid valve includes An evaporative fuel processing apparatus, wherein the evaporative fuel passage is connected to a fuel tank side and a second passage portion of the electromagnetic valve is connected to a canister side.

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