JP5811890B2 - Fuel tank system - Google Patents

Description

  The present invention relates to a fuel tank system.

  Patent Document 1 describes an evaporative fuel discharge suppression device in which an electromagnetic block valve (open / close valve) is disposed on an evaporation line from a fuel tank to a canister. In the configuration described in this document, a closed fuel tank system can be configured by completely closing the evaporation line by a blocking valve.

  In the fuel tank system having the above structure, when the valve body of the blocking valve moves to the valve open position, the tank internal pressure (positive pressure) of the fuel tank acts on the back surface (front surface in the moving direction) of the valve body. The driving force required to open the valve increases, leading to an increase in the size of the block valve (solenoid valve).

JP 2005-104394 A

  In view of the above facts, an object of the present invention is to obtain a fuel tank system capable of downsizing a solenoid valve of a pipe that communicates a fuel tank and a canister.

In the first and second aspects of the invention, a fuel tank that can accommodate fuel therein, a canister that adsorbs and desorbs evaporated fuel generated in the fuel tank with an adsorbent, and an interior of the canister An atmosphere release pipe for releasing the atmosphere, a vent pipe for communicating the fuel tank and the canister through the fuel tank and sending the evaporated fuel in the fuel tank to the canister, and a tank internal pressure of the fuel tank acting on the vent pipe When the valve member main body moves when the pressure of the main chamber becomes higher than the pressure of the back pressure chamber. A valve member that opens and communicates with the vent pipe; a tank-side bypass passage that communicates the tank-side vent pipe and the back pressure chamber from the fuel tank to the valve member in the vent pipe; A canister side bypass pipe capable of communicating the canister side vent pipe and the back pressure chamber from the valve member to the canister in the vent pipe, and a solenoid valve controlled to open and close the canister side bypass path, And a valve opening means for opening the valve member by operation.

  In this fuel tank system, the fuel tank and the canister can communicate with each other through a vent pipe. The vent pipe is provided with a bypass path from the tank side bypass passage through the back pressure chamber to the canister side bypass passage. The vent pipe is blocked by the valve member so as not to communicate, and the solenoid valve provided in the canister-side bypass passage is closed so that the evaporated fuel in the fuel tank can be sealed so as not to move to the canister. .

  When a large amount of evaporated fuel in the fuel tank is sent to the canister, when the control device opens the electromagnetic valve, the canister-side bypass passage is opened, so that the back pressure chamber is opened to the atmosphere. On the other hand, since the tank internal pressure (positive pressure) acts on the main chamber, the pressure in the main chamber is relatively higher than the pressure in the back pressure chamber. When the pressure difference between the back pressure chamber and the main chamber exceeds the valve opening pressure of the valve member, the valve member main body moves to the valve opening position and connects the vent pipe. As a result, the back pressure chamber is opened to the atmosphere, so that the force required for the operation of the valve member for opening the vent pipe is smaller than the configuration in which the back pressure chamber is not opened to the atmosphere. The valve opening pressure becomes smaller.

  Further, this fuel tank system is provided with valve opening means, and the valve member can be opened by operating the valve opening means. For example, when the back pressure chamber cannot be opened to the atmosphere for some reason or when the valve member is not opened even if the back pressure chamber can be opened to the atmosphere, the valve member can be opened by operation.

In particular, in the first aspect of the invention, the valve opening means is provided in the electromagnetic valve bypass passage that bypasses the electromagnetic valve and communicates the back pressure chamber and the canister side vent pipe, and the electromagnetic valve bypass passage. And a manually operated valve that can manually open the electromagnetic valve bypass passage .

  Therefore, when the manually operated valve is opened manually, the back pressure chamber is opened to the atmosphere via the electromagnetic valve bypass passage, so that the pressure in the back pressure chamber decreases. When the internal pressure of the fuel tank acts on the main chamber and the pressure difference between the back pressure chamber and the main chamber exceeds the valve opening pressure of the valve member and the valve member body moves to the valve open position, the valve member opens. Is done. For example, the valve member can be opened even when the electromagnetic valve is in a malfunctioning state.

According to a second aspect of the present invention, the valve opening means includes an electromagnetic valve operating member that manually opens the electromagnetic valve.

  When the solenoid valve operating member is operated and the solenoid valve is manually opened, the back pressure chamber is opened to the atmosphere through the canister-side bypass passage, so that the pressure in the back pressure chamber decreases. When the internal pressure of the fuel tank acts on the main chamber and the pressure difference between the back pressure chamber and the main chamber exceeds the valve opening pressure of the valve member and the valve member body moves to the valve open position, the valve member opens. Is done. For example, the valve member can be opened even when the electromagnetic valve is in a malfunctioning state.

  In addition, since the back pressure chamber is opened to the atmosphere by directly opening the solenoid valve, a passage or the like for bypassing the solenoid valve becomes unnecessary.

  Since the present invention is configured as described above, it is possible to reduce the size of the solenoid valve of the pipe that communicates the fuel tank and the canister.

1 is a schematic diagram illustrating an overall configuration of a fuel tank system according to a first embodiment of the present invention. FIG. 3 is a partially enlarged cross-sectional view of the fuel tank system according to the first embodiment of the present invention with a diaphragm valve and a solenoid valve closed. It is sectional drawing which expands partially and shows a state with the diaphragm valve closed and the solenoid valve opened in the fuel tank system of 1st Embodiment of this invention. It is sectional drawing shown in the state which the diaphragm valve and the solenoid valve opened in the fuel tank system of 1st Embodiment of this invention. It is sectional drawing shown in the state which operated the operation part in order to open a diaphragm valve by manual operation in the fuel tank system of 1st Embodiment of this invention. It is sectional drawing shown in the state which the diaphragm valve opened in the fuel tank system of 1st Embodiment of this invention, and the solenoid valve opened. It is sectional drawing which expands partially and shows the state which the diaphragm valve and the solenoid valve closed in the fuel tank system of 2nd Embodiment of this invention. It is sectional drawing which expands partially and shows a state with the diaphragm valve and the solenoid valve closed in the fuel tank system of 3rd Embodiment of this invention. It is sectional drawing which expands partially and shows a diaphragm valve and a solenoid valve in the state which closed the fuel tank system of the 1st reference example of this invention. The fuel tank system of the second reference example of the present invention is shown partially enlarged, (A) is a state where the diaphragm valve and the electromagnetic valve are closed, (B) is a state where the diaphragm valve is the back pressure chamber and the main chamber A state in which the valve is opened due to the pressure difference, (C) is a state in which the diaphragm valve is opened manually. It is sectional drawing which expands partially and shows a state with the diaphragm valve and the solenoid valve closed in the fuel tank system of the 3rd reference example of this invention. It is sectional drawing which expands partially and shows the state which the diaphragm valve and the solenoid valve closed in the fuel tank system of the modification of 1st Embodiment of this invention.

  FIG. 1 shows a fuel tank system 12 according to a first embodiment of the present invention. The fuel tank system 12 includes a fuel tank 14 that can store fuel therein.

  A lower portion of an oil supply pipe 82 is connected to the fuel tank 14. The upper end of the oil supply pipe 82 is an oil supply port 16, and an oil supply gun can be inserted into the oil supply port 16 to supply oil to the fuel tank 14. Except when refueling, the refueling port 16 is closed with a cap 18 for a refueling port, for example.

  The body panel of the automobile is provided with a flat box-shaped lid box 84 (see FIG. 2) that accommodates the filler port 16 and the filler port cap 18. The lid box 84 is opened toward the outside of the vehicle body, and a lid 20 is provided to cover the open part from the outside of the vehicle body. In a state where the lid 20 covers the lid box 84 (closed state), it is not possible to supply oil from the oil supply port 16 and to operate the valve operating portion 94 as described later.

  The lid 20 is rotated in the direction of arrow R <b> 1 by the control device 32 by operating the lid opener switch 22. When the lid 20 is thus rotated in the direction of the arrow R1 (open state), the fuel filler cap 18 can be detached from the fuel filler port 16 and a fuel gun can be inserted into the fuel filler port 16. In addition, the valve operation unit 94 can be operated.

  The open / closed state of the lid 20 is detected by the lid open / close sensor 20 </ b> S and sent to the control device 32. In the present embodiment, the state in which the lid 20 is opened is regarded as the “fuel supply state to the fuel tank”, and the lid opening / closing sensor 20S is an example of a fuel supply state sensor. As the oil supply state sensor, a sensor for detecting the attachment / detachment state of the oil supply port cap 18 may be used instead of the lid opening / closing sensor 20S.

  A display unit 86 is connected to the control device 32. The display unit 86 can display whether or not it is actually possible to supply fuel when the lid opener switch 22 is operated at the time of fuel supply to the fuel tank 14.

  A fuel pump 24 is provided in the fuel tank 14. The fuel pump 24 and the engine 26 are connected by a fuel supply pipe 28. By driving the fuel pump 24, the fuel in the fuel tank 14 can be sent to the engine 26 through the fuel supply pipe 28.

  The fuel tank 14 is provided with a tank internal pressure sensor 30. The tank internal pressure sensor 30 detects the tank internal pressure of the fuel tank 14 and sends the information to the control device 32.

  The fuel tank system 12 is provided with a canister 34. Inside the canister 34, an adsorbent (activated carbon or the like) capable of adsorbing evaporated fuel is accommodated. The canister 34 and the upper part of the fuel tank 14 are connected by a vent pipe 36. The evaporated fuel generated in the fuel tank 14 is sent to the canister 34 through the vent pipe 36.

  Connected to the canister 34 are a purge pipe 38 that communicates with the engine 26 and an air release pipe 40 that opens the canister 34 to the atmosphere. When the engine 26 is driven, the evaporated fuel adsorbed by the adsorbent in the canister 34 can be desorbed and sent to the engine 26 by applying the negative pressure of the engine 26. At this time, the atmosphere is introduced into the canister 34 through the atmosphere opening pipe 40.

  The air release pipe 40 is provided with a diagnostic pump 42. The diagnostic pump 42 is controlled by the control device 32. The diagnostic pump 42 is used when diagnosing a failure or the like of the fuel tank system 12 by applying a predetermined pressure to the fuel tank system 12 through the canister 34.

  A full tank regulating valve 44 is attached to one end of the vent pipe 36 (the end in the fuel tank 14). When the fuel level in the fuel tank 14 is below a predetermined full level, the full tank regulating valve 44 is opened, and the gas containing the evaporated fuel in the fuel tank 14 can be sent to the canister 34. When the fuel liquid level in the fuel tank 14 exceeds a predetermined liquid level (full tank liquid level), the full tank regulating valve 44 is closed. Thereby, the gas in the fuel tank 14 does not flow to the canister 34. In this state, when fuel is further supplied into the fuel tank 14, the fuel ascends the fuel supply pipe 82 and reaches the fuel supply gun. When the auto-stop function of the refueling gun is activated, refueling is stopped.

  A diaphragm valve 46 is provided at an intermediate portion of the vent pipe 36 (a portion between the fuel tank 14 and the canister 34). The diaphragm valve 46 is an example of the valve member of the present invention. Hereinafter, the vent pipe 36 on the fuel tank side with respect to the diaphragm valve 46 is referred to as a tank side vent pipe 36T and the vent pipe 36 on the canister 34 side with respect to the diaphragm valve 46 is referred to as a canister side vent pipe 36C.

  As shown in detail in FIG. 2, the diaphragm valve 46 has a valve housing 48 in which the other end side of the tank side vent pipe 36 </ b> T is expanded in a flat cylindrical shape. Inside the valve housing 48, one end side of the canister side vent pipe 36 </ b> C is accommodated so as to be coaxial with the valve housing 48, and a valve seat 50 is configured. A portion between the valve seat 50 and the valve housing 48 is a main chamber 52. As can be seen from FIG. 1, the main chamber 52 can communicate with the inside of the fuel tank 14 through the tank side vent pipe 36T.

  The opening at the upper end of the valve seat 50 can be closed by the valve member main body 54. The periphery of the valve member main body 54 is fixed to the inner peripheral surface of the valve housing 48 by a diaphragm 56. The space above the valve member main body 54 and the diaphragm 56 in FIG. 2 is a back pressure chamber 58. Therefore, the main chamber 52 and the back pressure chamber 58 are partitioned by the diaphragm 56.

  The area (pressure receiving area) where the valve member main body 54 and the diaphragm 56 receive pressure is such that the pressure receiving area on the back pressure chamber 58 side is equal to the cross sectional area of the valve seat 50 than the pressure receiving area on the main chamber 52 side. It is getting wider.

  A compression coil spring 60 is accommodated in the back pressure chamber 58. The compression coil spring 60 applies a predetermined spring force in the direction toward the valve seat 50 (arrow S1 direction) to the valve member main body 54. Further, the diaphragm 56 also applies a predetermined spring force in the direction of the arrow S1 to the valve member main body 54. Thereby, the valve member main body 54 is urged in a direction to close the opening portion of the valve seat 50. For example, when the internal pressure of the main chamber 52 and the internal pressure of the back pressure chamber 58 are approximately the same, the valve member main body 54 is in close contact with the opening portion of the valve seat 50. As a result, the diaphragm valve 46 is closed, and movement of gas in the vent pipe 36 is prevented.

  On the other hand, for example, when the back pressure chamber 58 becomes a predetermined negative pressure or higher than the main chamber 52 (in which the internal pressure is low), the valve member main body 54 moves against the spring force of the compression coil spring 60 and the diaphragm 56. It moves to the pressure chamber 58 side, and the opening part of the valve seat 50 is opened. Thereby, the diaphragm valve 46 is opened, and gas can be moved in the vent pipe 36.

  A tank-side bypass passage 62 is provided between the tank-side vent pipe 36T and the back pressure chamber 58. Gas can move between the fuel tank 14 and the back pressure chamber 58 through the tank side bypass passage 62.

  The tank-side bypass passage 62 is provided with a reduced diameter portion 64 having a locally reduced inner diameter. Due to the reduced diameter portion 64, a predetermined resistance is generated in the movement of the gas between the fuel tank 14 and the back pressure chamber 58.

  As described above, the means for causing the gas between the fuel tank 14 and the back pressure chamber 58 to generate a predetermined resistance is not limited to a structure in which the tank-side bypass passage 62 is locally reduced in diameter. For example, the inner diameter of the tank-side bypass passage 62 may be reduced as a whole to cause a predetermined resistance to gas movement. Furthermore, the tank-side bypass passage 62 may be bent at a predetermined position (may be bent or curved) to cause a predetermined resistance to gas movement.

  A canister-side bypass passage 66 is provided between the canister-side vent pipe 36 </ b> C and the back pressure chamber 58. An electromagnetic valve 68 that is controlled to be opened and closed by the control device 32 is provided in an intermediate portion of the canister side bypass passage 66.

  The solenoid valve 68 has a solenoid valve housing 70. In the electromagnetic valve housing 70, a coil portion 72 that is energized and controlled by the control device 32, a plunger portion 74 that moves in the arrow S2 direction and the opposite direction in response to a driving force from the coil portion 72, and a plunger portion A disc-shaped solenoid valve main body 76 provided at the tip of 74 is provided. Further, a part (intermediate part) of the canister-side bypass passage 66 passes through the electromagnetic valve housing 70.

  The electromagnetic valve body 76 closes the canister-side bypass passage 66 in a state where the solenoid valve body 76 is in contact with a valve seat 78 provided in the canister-side bypass passage 66. On the other hand, as shown in FIG. 3, when the solenoid valve body 76 is separated from the valve seat 78, the gas can move through the canister-side bypass passage 66. In the present embodiment, the direction in which the solenoid valve main body 76 moves away from the valve seat 78, that is, the moving direction of the solenoid valve main body 76 when opening the canister-side bypass passage 66 is a direction in which positive pressure from the back pressure chamber 58 is received. The direction of the solenoid valve main body 76 is set so as to match.

  A compression coil spring 80 is attached to the plunger portion 74. The compression coil spring 80 applies a predetermined spring force to the electromagnetic valve body 76 in the direction of the arrow S2, so that the electromagnetic valve body 76 is inadvertently separated from the valve seat 78 when not controlled by the control device 32. I am trying not to.

  An electromagnetic valve bypass passage 88 that bypasses the electromagnetic valve 68 is provided between the back pressure chamber 58 and the electromagnetic valve 68 in the canister side bypass passage 66 and between the canister side vent pipe 36 </ b> C.

  As shown in FIG. 1, the intermediate portion of the solenoid valve bypass passage 88 extends to the vicinity of the lid box 84. A manual operation valve 90 is provided in a portion adjacent to the lid box 84.

  The manual operation valve 90 includes an operation valve main body 92 that opens and closes the electromagnetic valve bypass passage 88 and a valve operation portion 94 for operating the operation valve main body 92. The valve operating unit 94 is located in the lid box 84, and the operator operates the valve operating unit in a state in which the lid 20 is opened (the state shown in FIGS. 3 and 4 and also shown by a two-dot chain line in FIG. 2). 94 can be picked and operated.

  The position of the valve operating portion 94 is set so as to be pushed by the lid 20 when the lid 20 is in the closed state, and to maintain the operation valve main body 92 in the valve closing position. Normally, the operation valve main body 92 is in the valve closing position and closes the solenoid valve bypass passage 88. However, by operating the lid 20 in the open state and pulling the valve operation portion 94 forward (in the direction of the arrow PL), the operation valve main body 92 is closed. The main body 92 can be opened. In the valve open state, the operation valve main body 92 opens the electromagnetic valve bypass passage 88.

  Next, the operation of the fuel tank system 12 of this embodiment will be described.

  In the fuel tank system 12 of the present embodiment, in a normal state, that is, in a state where the fuel tank 14 is not refueled (the vehicle may be traveling or parked), as shown in FIG. The solenoid valve body 76 of the solenoid valve 68 is closed. The lid 20 is in a closed state, and the operation valve main body 92 of the manual operation valve 90 is also closed (the electromagnetic valve bypass passage 88 is closed). The valve member main body 54 of the diaphragm valve 46 is also closed. For this reason, the tank internal pressure of the fuel tank 14 acts on both the main chamber 52 and the back pressure chamber 58 of the diaphragm valve 46. The diaphragm valve 46 is maintained in a closed state by the spring force of the compression coil spring 60 and the diaphragm 56 and is not opened carelessly.

  When the lid opener switch 22 is operated during fuel supply, the control device 32 opens the lid 20. Further, the control device 32 opens the electromagnetic valve 68 as shown in FIG. As a result, the back pressure chamber 58 of the diaphragm valve 46 is opened to the atmosphere from the atmosphere opening pipe 40 through the canister 34, the canister side vent pipe 36 </ b> C, and the canister side bypass passage 66. That is, the pressure in the back pressure chamber 58 decreases and approaches atmospheric pressure.

  On the other hand, the main chamber 52 is also opened to the atmosphere from the back pressure chamber 58 through the tank side bypass passage 62 and the tank side vent pipe 36T. However, in this embodiment, the tank-side bypass passage 62 is provided with the reduced diameter portion 64, and a predetermined resistance is generated in the movement of gas between the main chamber 52 and the back pressure chamber 58. It takes a long time for the pressure to be comparable to the pressure in the back pressure chamber 58. That is, the pressure difference is generated between the back pressure chamber 58 and the main chamber 52 (the pressure in the back pressure chamber 58 is lower than that in the main chamber 52). Therefore, the diaphragm valve 46 can be opened with a smaller valve opening pressure as compared with a configuration in which such a pressure difference does not occur between the back pressure chamber 58 and the main chamber 52. Thereby, as shown in FIG. 4, the valve member main body 54 moves to the back pressure chamber 58 side (upper side), and the diaphragm valve 46 is opened.

  When the diaphragm valve 46 is opened in this way, the tank internal pressure of the fuel tank 14 also decreases, and the fuel can be supplied. The control device 32 determines from the information such as the tank internal pressure detected by the tank internal pressure sensor 30 that the refueling is possible, and displays on the display unit 86 that the refueling is possible.

  Here, in order to open the diaphragm valve 46 with a small valve opening pressure, it is conceivable to downsize the valve member main body 54. However, since the valve member main body 54 is a member that closes the valve seat 50, when the valve member main body 54 is downsized, it is necessary to reduce the inner diameter of the valve seat 50, that is, a part of the canister side vent pipe 36C. . Therefore, it is desirable to increase the diameter of the valve seat 50 from the viewpoint of securing the flow rate of the vent pipe 36 when the diaphragm valve 46 is opened. Along with this, the valve member main body 54 also becomes large, but even the valve member main body 54 thus enlarged can be opened with a small valve opening pressure.

  In the present embodiment, the valve member main body 54 of the diaphragm valve 46 can be enlarged as described above, whereas the electromagnetic valve main body 76 of the electromagnetic valve 68 needs to exhibit an action of opening and closing the vent pipe 36 (the valve seat 50). Since it is sufficient that the canister side bypass passage 66 can be opened and closed, the size can be reduced. Since the area of the electromagnetic valve body 76 that receives the tank internal pressure of the fuel tank 14 is also reduced, the pressing load (load in the direction of arrow S2 in FIG. 2) necessary for closing the electromagnetic valve 68 can be reduced. As a result, the electromagnetic valve 68 can be reduced in size and power consumption, and the fuel tank system 12 having low cost and excellent fuel efficiency can be obtained.

  In particular, in this embodiment, the valve opening direction of the solenoid valve body 76 of the solenoid valve 68 coincides with the direction in which positive pressure acts on the solenoid valve body 76 from the back pressure chamber 58 (as indicated by the arrow S2 in FIG. 2). Opposite direction). For this reason, the driving force from the coil part 72 for moving the solenoid valve main body 76 in the valve opening direction can be reduced, and power saving can be further measured.

  In the present embodiment, as described above, even if the inner diameter of the valve seat 50 is increased, the valve opening pressure of the diaphragm valve 46, that is, the force required for the operation of the valve member main body 54 can be reduced. By increasing the inner diameter of the valve seat 50, that is, the vent pipe 36, the ventilation resistance of the vent pipe 36 can be reduced. As a result, the evaporated fuel generated in the fuel tank 14 during refueling easily flows to the canister 34 through the vent pipe 36, and the fuel tank system 12 that facilitates refueling is obtained.

  Further, before refueling, the diaphragm valve 46 is opened, so that the tank internal pressure of the fuel tank 14 is reduced. In the present embodiment, by reducing the ventilation resistance of the vent pipe 36, the time required for lowering the tank internal pressure is shortened, and refueling in a shorter time becomes possible.

  Here, let us consider a case where the refueling enabled state is not achieved even though the lid opener switch 22 is operated (the refueling disabled state). The inability to refuel can be determined, for example, because the tank internal pressure of the fuel tank 14 detected by the tank internal pressure sensor 30 does not decrease as expected. Alternatively, it is possible to know, for example, by detecting disconnection of the electromagnetic valve 68 or a voltage abnormality of a battery (not shown). In the case where the refueling is disabled, the control device 32 displays on the display unit 86 that the “refueling disabled state” is displayed (or by not displaying the “refueling enabled state”, as a result, the refueling is performed. May indicate that this is not possible).

  When the operator of the refueling operation confirms the “non-refueling state” on the display unit 86, as shown in FIG. 5, the valve operation unit 94 is manually operated (pulled in the direction of the arrow PL in the illustrated example). The valve body 92 is set to the valve opening position. As a result, even if the electromagnetic valve 68 is closed, the back pressure chamber 58 communicates with the canister 34 through a part of the canister-side bypass passage 66, the electromagnetic valve bypass passage 88, and the canister-side vent pipe 36C, and is released to the atmosphere. Is done. The tank internal pressure of the fuel tank 14 acts on the main chamber 52, and the diaphragm valve 46 is opened as the pressure in the back pressure chamber 58 decreases, so that the tank internal pressure of the fuel tank 14 decreases and refueling is possible. It becomes.

  As described above, in the fuel tank system 12 according to the present embodiment, even if an abnormality or the like of the electromagnetic valve 68 occurs, the fuel tank 14 can be refueled by opening the back pressure chamber 58 to the atmosphere.

  Even in the state where the manual operation valve 90 is opened, the gas (including the evaporated fuel) in the back pressure chamber 58 is released to the atmosphere after passing through the canister 34. Since the evaporated fuel in the gas is adsorbed by the adsorbent of the canister 34, the release of the evaporated fuel to the atmosphere can be suppressed.

  In the first embodiment, the valve operation unit 94 is provided inside the lid box 84 (a portion closed by the lid 20). Since it is necessary to open the lid 20 to operate the valve operation unit 94, it is possible to prevent a situation in which the valve operation unit 94 is operated except when necessary.

  The valve operation unit 94 is set to a position where the operation valve main body 92 is closed by closing the lid 20. Therefore, it is possible to prevent the operation valve main body 92 from being maintained in an open state other than when necessary.

  While the vehicle is running, the tank internal pressure of the fuel tank 14 is detected by the tank internal pressure sensor 30 as shown in FIG. When the tank internal pressure does not exceed a predetermined value set in advance, the control device 32 closes the electromagnetic valve 68 as shown in FIG. Since the diaphragm valve 46 is also closed, the fuel tank 14 is sealed. The evaporated fuel generated in the fuel tank 14 does not move to the canister 34.

  When the tank internal pressure exceeds a predetermined value, the control device 32 controls opening and closing of the electromagnetic valve 68. When the solenoid valve 68 is opened (the same state as shown in FIG. 3), the tank side vent pipe 36T, the tank side bypass passage 62, the back pressure chamber 58, the canister side bypass passage 66, the canister side vent pipe 36C. Then, the evaporated fuel can move to the canister 34.

  Then, by appropriately opening and closing the electromagnetic valve 68, it is possible to control the flow rate of the evaporated fuel flowing through the vent pipe 36 and the tank internal pressure. In this case, the opening / closing control of the electromagnetic valve 68 may be performed by adjusting the movement amount of the electromagnetic valve body 76 in the arrow S2 direction or in the opposite direction to adjust the cross-sectional area of the flow path. Moreover, you may perform by duty control (control of the time which switches the valve-opening position and valve-closing position of the valve member main body 54).

  The evaporated fuel discharged from the fuel tank 14 through the vent pipe 36 in this way may be adsorbed by the adsorbent of the canister 34. However, when the engine 26 is driven, it further passes through the purge pipe 38. It may be sent to the engine 26 and burned by the engine 26.

  Moreover, in the fuel tank system 12 of the present embodiment, the member for adjusting the flow rate in the vent pipe 36 when the tank internal pressure exceeds a predetermined value as described above is used as an electromagnetic for opening the back pressure chamber 58 to the atmosphere during refueling. The valve 68 is also used. Therefore, compared with the structure which provided the member which show | plays these effect | actions separately, while being able to comprise at low cost, it becomes lightweight.

  Even while the vehicle is parked, the electromagnetic valve 68 and the diaphragm valve 46 are normally closed, so that the fuel tank 14 is sealed. The evaporated fuel generated in the fuel tank 14 does not move to the canister 34.

  When the tank internal pressure of the fuel tank 14 becomes a positive pressure (a state higher than the atmospheric pressure) while the vehicle is parked, the tank internal pressure passes through the back pressure chamber 58 and opens the electromagnetic valve body 76 of the electromagnetic valve 68. Acting in the direction opposite to the arrow S2 shown in FIG. During parking, the electromagnetic valve 68 is not controlled to be opened and closed by the control device 32. However, when the tank internal pressure exceeds a predetermined threshold (hereinafter referred to as “positive pressure threshold”), the electromagnetic valve body 76 that has received the tank internal pressure (positive pressure) resists the spring force of the compression coil spring 80. It moves in the valve opening direction, and the state is similar to the state shown in FIG. That is, the solenoid valve 68 operates as a positive pressure release valve that releases the positive pressure of the fuel tank 14, and it is not necessary to newly provide the positive pressure release valve. Therefore, compared with the structure which provided the positive pressure release valve separately, while being able to comprise at low cost, it becomes lightweight.

  Moreover, the solenoid valve 68 in the fuel tank system 12 of the present embodiment is controlled to open and close under predetermined conditions even during refueling and traveling as described above. In other words, the electromagnetic valve main body 76 moves between the valve opening position and the valve closing position even when the tank internal pressure exceeds the positive pressure threshold. For this reason, compared with a positive pressure release valve that is opened only when the tank internal pressure exceeds the positive pressure threshold, a phenomenon in which the electromagnetic valve body 76 is inadvertently fixed to the valve seat 78 is less likely to occur, Fixing property is improved.

  When the tank internal pressure of the fuel tank 14 becomes negative (a state lower than atmospheric pressure) while the vehicle is parked, the tank internal pressure (negative pressure) passes through the back pressure chamber 58 and the valve member main body 54 of the diaphragm valve 46. Acts in the direction to open the valve (the direction opposite to the arrow S1 shown in FIG. 2). When the tank internal pressure becomes lower than a predetermined threshold (hereinafter referred to as “negative pressure threshold”), as shown in FIG. 5, the valve member main body 54 receives the tank internal pressure (negative pressure) from the back pressure chamber 58 side. However, it moves in the valve opening direction against the spring force of the compression coil spring 60 and the diaphragm 56. That is, the diaphragm valve 46 operates as a negative pressure release valve that releases the negative pressure of the fuel tank 14, and it is not necessary to newly provide the negative pressure release valve. Therefore, compared with the structure which provided the negative pressure release valve separately, while being able to comprise at low cost, it becomes lightweight.

  Moreover, as described above, the diaphragm valve 46 in the fuel tank system 12 of the present embodiment is opened and closed under a predetermined condition even during refueling. In other words, the valve member main body 54 moves between the valve open position and the valve close position even when the tank internal pressure falls below the negative pressure threshold. For this reason, compared to a negative pressure release valve that is opened only when the tank internal pressure falls below the negative pressure threshold, a phenomenon in which the valve member main body 54 is inadvertently fixed to the valve seat 50 is less likely to occur. Fixing property is improved.

  FIG. 7 shows the fuel tank system 112 according to the second embodiment of the present invention partially enlarged at the diaphragm valve 46, the electromagnetic valve 68, and the vicinity thereof. In the second embodiment, the overall configuration of the fuel tank system 112 is the same as that of the first embodiment, and thus illustration is omitted. Moreover, in 2nd Embodiment, the same code | symbol is attached | subjected about the same component, member, etc. as 1st Embodiment, and detailed description is abbreviate | omitted.

  In the fuel tank system 112 of the second embodiment, the solenoid valve bypass passage 88 is not extended to the lid box 84 but is located in the vicinity of the solenoid valve 68. The operation valve main body 92 of the manual operation valve 90 is also disposed in the vicinity of the electromagnetic valve 68.

  One end of a wire 114 is connected to the operation valve main body 92, and a valve operation unit 94 is connected to the other end of the wire 114. By pulling the valve operation portion 94 in the direction of the arrow PL, the operation valve main body 92 can be opened / closed via the wire 114.

  The fuel tank system 112 according to the second embodiment configured as described above also has the same operational effects as the fuel tank system 12 according to the first embodiment.

  In particular, in the second embodiment, the length of the solenoid valve bypass passage 88 can be set shorter than in the first embodiment, so that the cost and weight can be reduced.

  In FIG. 8, a fuel tank system 122 according to a third embodiment of the present invention is shown partially enlarged at the diaphragm valve 46, the electromagnetic valve 68, and the vicinity thereof. In the third embodiment, the overall configuration of the fuel tank system 122 is the same as that of the first embodiment, and hence illustration thereof is omitted. In the third embodiment, the same components and members as those in the first embodiment or the second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the fuel tank system 122 of the third embodiment, the solenoid valve bypass passage 88 (see FIGS. 1 and 2 etc.) is not provided. One end of the wire 114 is connected to the plunger portion 74 of the electromagnetic valve 68. Therefore, in the fuel tank system 122 of the third embodiment, the electromagnetic valve 68 can be directly opened by pulling the valve operating portion 94 in the direction of the arrow PL. The valve operating portion 94 and the wire 114 constitute the electromagnetic valve operating member 124 of the present invention.

  The fuel tank system 122 of the third embodiment having such a configuration also has substantially the same operational effects as the fuel tank systems 12 and 112 of the first and second embodiments.

  In particular, in the “non-refueling state”, when the valve operating portion 94 is operated manually (pulled in the direction of arrow PL in the illustrated example), the electromagnetic valve 68 is opened and the back pressure chamber 58 is opened to the atmosphere. . The tank internal pressure of the fuel tank 14 acts on the main chamber 52, and the diaphragm valve 46 is opened as the pressure in the back pressure chamber 58 decreases, so that the tank internal pressure of the fuel tank 14 decreases and refueling is possible. It becomes.

  Further, in the third embodiment, since the solenoid valve bypass passage 88 is unnecessary, it can contribute to further cost reduction and weight reduction as compared with the first embodiment and the second embodiment.

FIG. 9 shows the fuel tank system 132 of the first reference example of the present invention partially enlarged at the diaphragm valve 46, the electromagnetic valve 68, and the vicinity thereof. In the first reference example , the overall configuration of the fuel tank system 132 is the same as that of the first embodiment, and thus illustration thereof is omitted. In the first reference example , the same components and members as those in the first to third embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

In the fuel tank system 132 of the first reference example , the solenoid valve bypass passage 88 (see FIGS. 1 and 2) is not provided. One end of the wire 114 is connected to the diaphragm valve 46 from the valve opening direction side (the upper side in FIG. 9). Therefore, in the fuel tank system 132 of the first reference example , the diaphragm valve 46 can be directly opened by pulling the valve operating portion 94 in the direction of the arrow PL. The valve operation portion 134 of the present invention is configured by the valve operation portion 94 and the wire 114.

The fuel tank system 132 of the first reference example configured as described above also has substantially the same operational effects as the fuel tank systems 12, 112, and 122 of the first to third embodiments.

  In particular, in the “non-refueling state”, when the valve operating portion 94 is manually operated (pulled in the direction of arrow PL in the illustrated example), the diaphragm valve 46 is opened, so that the tank internal pressure of the fuel tank 14 is reduced. It will drop and it will be possible to refuel.

Further, in the first reference example , the solenoid valve bypass passage 88 is unnecessary as in the third embodiment, so that it can contribute to further cost reduction and weight reduction as compared with the first embodiment and the second embodiment.

In the first reference example , the diaphragm valve 46 can be opened without depending on the opening of the electromagnetic valve 68. For example, the diaphragm valve 46 can be opened even when the inside of the canister-side bypass passage 66 is blocked for some reason (foreign matter or the like).

FIG. 10 shows a fuel tank system 142 of a second reference example of the present invention partially enlarged in the vicinity of the diaphragm valve 46 and the vicinity thereof. In the second reference example , the overall configuration of the fuel tank system 142 is the same as that of the first embodiment, and hence illustration thereof is omitted. In the second reference example , the same reference numerals are given to the same components and members as those in the first to third embodiments and the first reference example, and detailed description thereof is omitted.

As shown in FIG. 10A, in the fuel tank system 142 of the second reference example , the basic configuration is the same as that of the fuel tank system 132 of the first reference example , but one end of the wire 114 is used as a diaphragm valve. It is not connected directly. The first engagement member 144 is provided on the valve member main body 54 of the diaphragm valve 46, and the second engagement member 146 is provided on one end of the wire 114, which is different from the first reference example .

  The first engagement member 144 has a cylindrical portion 144C that protrudes in a substantially cylindrical shape from a substantially central portion of the valve member main body 54 (diaphragm 56) toward the inside of the back pressure chamber 58 (upward in the illustrated example). Yes. An annular portion 144R extends radially inward from the upper end of the cylindrical portion 144C. A portion near the tip of the wire 114 is inserted inside the annular portion 144R.

  The second engagement member 146 is configured by a disc portion 146 </ b> P formed at the tip of the wire 114. The disc part 146 </ b> P has a gap formed between the valve member main body 54 and the diaphragm 56 in a normal state (in a state where the disk part 146 </ b> P is not moved upward). 10B, when the valve member main body 54 and the diaphragm 56 move in the valve opening direction (upward) due to the pressure difference between the back pressure chamber 58 and the main chamber 52, they contact the disk portion 146P. Therefore, inadvertent resistance does not occur in this movement of the valve member main body 54 and the diaphragm 56.

  The outer diameter of the disc portion 146P is formed to be longer than the inner diameter of the annular portion 144R. Therefore, when the disc part 146P moves upward, it contacts and engages with the annular part 144R. When the disc portion 146P moves further upward in this state, the valve member main body 54 and the diaphragm 56 move upward via the first engagement member 144 as shown in FIG. 10C, and the diaphragm valve 46 becomes a valve-open state.

  When the disc portion 146P is not moved upward (the valve operating portion 94 is not pulled in the direction of the arrow PL), the moving direction of the disc portion 146P is between the disc portion 146P and the annular portion 144R. A gap may be formed in the (up and down direction), and the disc portion 146P and the annular portion 144R may be in contact with each other.

  Further, when the valve member main body 54 and the diaphragm 56 move in the valve opening direction (upward) due to the pressure difference between the back pressure chamber 58 and the main chamber 52, the valve member main body 54 and the diaphragm 56 are brought into contact with the disk portion 146P with a predetermined movement amount. May be. Thereby, since the movement amount of the valve member main body 54 in the valve opening direction is limited, the responsiveness when the valve member main body 54 moves in the valve closing direction (downward) is increased.

The fuel tank system 142 of the second reference example configured as described above also has substantially the same operational effects as the fuel tank system 134 of the first reference example .

In the second reference example , in particular, as shown in FIG. 10A, a gap is formed between the disc portion 146P, the valve member main body 54, and the diaphragm 56 in the normal state. Therefore, when the valve member main body 54 and the diaphragm 56 are moved in the valve opening direction (upward) due to the pressure difference between the back pressure chamber 58 and the main chamber 52 during refueling or the like (see FIG. 10B). Inadvertent resistance does not occur due to contact with the disk portion 146P on the way, and the diaphragm valve 46 can be closed more reliably.

In the second reference example , when the valve operating portion 94 is operated in the “non-oil supply state” (pulled in the direction of the arrow PL in the illustrated example), the disc portion 146P approaches and engages with the annular portion 144R. By operating the valve operating portion 94, the diaphragm valve 46 can be opened as shown in FIG. Then, the fuel tank 14 can be refueled due to a drop in the tank internal pressure.

Further, in the second reference example , similarly to the third embodiment and the first reference example , the solenoid valve bypass passage 88 is unnecessary, so that the cost and weight are further reduced as compared with the first embodiment and the second embodiment. Can contribute to

Further, in the second reference example , as in the first reference example , the diaphragm valve 46 can be opened without depending on the opening of the electromagnetic valve 68. That is, the diaphragm valve 46 can be opened even when the inside of the canister-side bypass passage 66 is blocked for some reason (foreign matter or the like).

In the second reference example , the first engagement member 144 and the second engagement member 146 are reversed, that is, the cylindrical portion 144C and the annular portion 144R are provided at one end of the cable 114, and the valve member The main body 54 (diaphragm 56) may be provided with a disk portion 146P via a support or the like.

FIG. 11 shows a fuel tank system 152 of a third reference example of the present invention partially enlarged in the vicinity of the diaphragm valve 46 and the vicinity thereof. In the third reference example , the overall configuration of the fuel tank system 152 is the same as that of the first embodiment, and thus illustration thereof is omitted. In the third reference example , the same components and members as those in the first to third embodiments, the first reference example, and the second reference example are denoted by the same reference numerals, and detailed description thereof is omitted.

In the fuel tank system 152 of the third reference example , not only the solenoid valve bypass passage 88 (see FIGS. 1 and 2) but also the canister side bypass passage 66 is not provided. A through hole 154 that penetrates the valve member main body 54 in the thickness direction is formed in the valve member main body 54 of the diaphragm valve 46. The through hole 154 communicates the canister side vent pipe 36C and the back pressure chamber 58, and serves as a canister side bypass passage in the present invention.

  The back pressure chamber 58 is provided with an electromagnetic valve 156. The solenoid valve 156 has a coil part 72, a plunger part 74, and a solenoid valve body 76, like the solenoid valve 68 of the first embodiment, so that the through hole 154 can be opened and closed by energizing the coil part 72. It has become.

In the third reference example , one end of the wire 114 is connected to the plunger portion 74 of the electromagnetic valve 156. Therefore, in the fuel tank system 152 of the third reference example , the electromagnetic valve 68 can be directly opened by pulling the valve operating portion 94 in the direction of the arrow PL.

In the third reference example , a positive pressure release passage 158 is provided between the canister side vent pipe 36C and the back pressure chamber 58, and a positive pressure release valve 160 is provided therein. The positive pressure release valve 160 is provided with an annular valve seat portion 162 in which the inner diameter of the positive pressure release passage 158 is locally reduced, and a positive pressure release hole 164 is formed at the center of the valve seat portion 162. ing. Further, a positive pressure release valve main body 166 capable of opening and closing the positive pressure release hole 164 is disposed on the canister side vent pipe 36 </ b> C side with respect to the valve seat portion 162. The positive pressure release valve main body 166 is urged by the compression coil spring 168 in the direction of closing the positive pressure release hole 164 (in the direction of arrow S3), but positive pressure equal to or higher than a predetermined positive pressure threshold is applied to the back pressure chamber 58. When acting from the side, it moves in the valve opening direction (direction opposite to the arrow S3) against the spring force of the compression coil spring 168, and opens the positive pressure release hole 164.

The fuel tank system 152 of the third reference example configured as described above also has substantially the same operational effects as the fuel tank systems 12, 112, 122, 132, 142 of the first to fifth embodiments.

  In particular, in the “non-refueling state”, when the valve operating portion 94 is operated manually (pulled in the direction of arrow PL in the illustrated example), the electromagnetic valve 68 is opened and the back pressure chamber 58 is opened to the atmosphere. . The tank internal pressure of the fuel tank 14 is acting on the main chamber 52, and the diaphragm valve 46 is opened as the pressure in the back pressure chamber 58 decreases. It becomes.

Further, in the third reference example , similarly to the third embodiment, the first reference example, and the second reference example , the electromagnetic valve bypass passage 88 is unnecessary, so that the cost is further reduced and the weight is reduced as compared with the second embodiment. Can contribute to

In addition, in the third reference example , since it is not necessary to provide the electromagnetic valve 68 outside the diaphragm valve 46, the fuel tank system 152 can be downsized.

In the second to third embodiments and the first to third reference examples , the position of the valve operating portion 94 (in which position on the vehicle body is arranged) is not particularly limited. For example, it may be arranged in the lid box 84 (see FIG. 2 etc.) as in the first embodiment. In particular, in the second to third embodiments and the first to third reference examples , since the degree of freedom of the shape of the wire 114 is high, the degree of freedom of the arrangement of the valve operation unit 94 is also high. Therefore, it may be arranged in the vicinity of the lid opener switch 22. Depending on the vehicle, there is a vehicle having a structure including an emergency release mechanism for the lid 20, but such a vehicle may be shared with the emergency release mechanism.

  In the above description, the solenoid valve body 76 of the solenoid valve 68 has a valve opening direction that coincides with the direction in which positive pressure acts from the back pressure chamber 58. However, the valve opening direction of the electromagnetic valve main body 76 is not limited to this, and the valve opening direction of the electromagnetic valve main body 76 is opposite to the direction of the positive pressure from the back pressure chamber 58 as shown in FIG. May be. In this configuration, the driving force from the coil portion 72 for maintaining the solenoid valve main body 76 in the valve closing position can be small.

  Although the diaphragm valve 46 is mentioned above as a valve member of the present invention, the valve member is not limited to the diaphragm valve 46. For example, the configuration may be such that the diaphragm 56 is eliminated and the valve member main body 54 is increased in diameter so that the outer periphery thereof is in contact with the inner periphery of the valve housing 48. In this configuration, the valve member main body 54 alone separates the main chamber 52 and the back pressure chamber 58, and the vent pipe 36 is closed by contacting the valve seat 50, and the vent is separated from the valve seat 50. The position where the pipe 36 is opened is moved.

12 Fuel tank system 14 Fuel tank 34 Canister 36 Vent pipe 36T Tank side vent pipe 36C Canister side vent pipe 40 Atmospheric release pipe 52 Main chamber 54 Valve member body 58 Back pressure chamber 62 Tank side bypass passage 66 Canister side bypass passage 68 Solenoid valve 88 Solenoid valve bypass passage (valve opening means)
90 Manually operated valve (opening means)
112 Fuel tank system 114 Wire (valve opening means)
122 Fuel tank system 124 Solenoid valve operating member 132 Fuel tank system 134 Valve member operating member 152 Fuel tank system 154 Through hole (canister side bypass passage)
156 Solenoid valve

Claims (2)

A fuel tank capable of containing fuel, and
A canister that adsorbs and desorbs evaporated fuel generated in the fuel tank with an adsorbent;
An air release pipe for opening the inside of the canister to the atmosphere;
A vent pipe for communicating the fuel tank and the canister to send the evaporated fuel in the fuel tank to the canister;
The vent pipe is divided into a main chamber provided so that a tank internal pressure of the fuel tank acts, and a back pressure chamber on the opposite side of the main chamber with the valve member body interposed therebetween, with respect to the pressure of the back pressure chamber A valve member that opens and communicates with the vent piping when the pressure in the main chamber increases and the valve member body moves; and
A tank side bypass passage communicating the tank side vent pipe and the back pressure chamber from the fuel tank to the valve member in the vent pipe;
A canister-side bypass passage capable of communicating the canister-side vent pipe and the back pressure chamber from the valve member to the canister in the vent pipe;
A solenoid valve controlled to open and close the canister-side bypass passage;
A solenoid valve bypass passage that bypasses the solenoid valve and communicates the back pressure chamber and the canister side vent pipe; a manually operated valve that is provided in the solenoid valve bypass passage and can be manually opened; and opening means for opening the said valve member comprising an operation,
Having fuel tank system. A fuel tank capable of containing fuel, and
A canister that adsorbs and desorbs evaporated fuel generated in the fuel tank with an adsorbent;
An air release pipe for opening the inside of the canister to the atmosphere;
A vent pipe for communicating the fuel tank and the canister to send the evaporated fuel in the fuel tank to the canister;
The vent pipe is divided into a main chamber provided so that a tank internal pressure of the fuel tank acts, and a back pressure chamber on the opposite side of the main chamber with the valve member body interposed therebetween, with respect to the pressure of the back pressure chamber A valve member that opens and communicates with the vent piping when the pressure in the main chamber increases and the valve member body moves; and
A tank side bypass passage communicating the tank side vent pipe and the back pressure chamber from the fuel tank to the valve member in the vent pipe;
A canister-side bypass passage capable of communicating the canister-side vent pipe and the back pressure chamber from the valve member to the canister in the vent pipe;
A solenoid valve controlled to open and close the canister-side bypass passage;
An electromagnetic valve operating member for manually opening the electromagnetic valve , and valve opening means for opening the valve member by operation;
Having fuel tank system.

Images