WO2018049114A1

WO2018049114A1 - Fuel vapor generation and delivery

Info

Publication number: WO2018049114A1
Application number: PCT/US2017/050610
Authority: WO
Inventors: Matthew MEMMER
Original assignee: Eaton Corporation
Priority date: 2016-09-08
Filing date: 2017-09-08
Publication date: 2018-03-15

Abstract

A vapor management system configured for use with a fuel tank that stores and delivers fuel to an internal combustion engine includes a vapor management device, a carbon canister and a three-way valve. The vapor management device has a fuel vapor generator. The carbon canister is adapted to collect fuel vapor emitted by the fuel tank. The three-way valve selectively connects the vapor management device with the internal combustion engine and the carbon canister. The fuel vapor generator is configured to selectively generate fuel vapor. The three-way valve is configured to open to a position that communicates the fuel vapor from the vapor management device to the internal combustion engine.

Description

FUEL VAPOR GENERATION AND DELIVERY

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Patent Application No. 62/384,964 filed on September 8, 2016. The disclosure of the above application is incorporated herein by reference.

FIELD

[0002] The present disclosure relates generally to fuel tanks on passenger vehicles and more particularly to a fuel tank having an electronically controlled module that manages the complete evaporative system for the vehicle, the fuel system having electronic controls on and/or in the fuel tank to allow for the control of vapor delivery and the generation of vapors if required.

BACKGROUND

[0003] Fuel vapor emission control systems are becoming increasingly more complex, in large part in order to comply with environmental and safety regulations imposed on manufacturers of gasoline powered vehicles. Along with the ensuing overall system complexity, complexity of individual components within the system has also increased. Certain regulations affecting the gasoline-powered vehicle industry require that fuel vapor emission from a fuel tank's ventilation system be stored during periods of an engine's operation. In order for the overall vapor emission control system to continue to function for its intended purpose, periodic purging of stored hydrocarbon vapors is necessary during operation of the vehicle.

[0004] The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. SUMMARY

[0005] A vapor management system configured for use with a fuel tank that stores and delivers fuel to an internal combustion engine includes a vapor management device, a carbon canister and a three-way valve. The vapor management device has a fuel vapor generator. The carbon canister is adapted to collect fuel vapor emitted by the fuel tank. The three-way valve selectively connects the vapor management device with the internal combustion engine and the carbon canister. The fuel vapor generator is configured to selectively generate fuel vapor. The three- way valve is configured to open to a position that communicates the fuel vapor from the vapor management device to the internal combustion engine.

[0006] According to additional features, a first vapor line is connected between the vapor management device and the three-way valve. A second vapor line is connected between the three-way valve and the carbon canister. A third vapor line is connected between the three-way valve and the internal combustion engine. The three-way valve operates in a first position where the first vapor line is open to the third vapor line but closed to the second vapor line. The three-way valve operates in a second position where the first vapor line is open to the second vapor line but closed to the third vapor line. The three-way valve operates in a third position where the second vapor line is open to the third vapor line but closed to the first vapor line. The three-way valve operates in a fourth position where the first, second and third vapor lines are all open to each other. In one example, the vapor generator is a fuel pump.

[0007] A vapor management system configured for use with a fuel tank that stores and delivers fuel to an internal combustion engine includes a vapor management device, a carbon canister and a three-way valve. The vapor management device has a fuel vapor generator that is configured to selectively generate fuel vapor. The carbon canister is adapted to collect fuel vapor emitted by the fuel tank. The three- way valve selectively connects the vapor management device with the internal combustion engine and the carbon canister. The three-way valve is configured to selectively and alternatively move to a first position and a second position. In the first position, the three-way valve communicates the fuel vapor from the vapor management device to the internal combustion engine. In the second position, the three-way valve communicates fuel vapor from the vapor management device to the carbon canister. [0008] In additional features, the three-way valve is configured to selectively and alternatively move to a third position that communicates fuel vapor between the internal combustion engine and the carbon canister. The three-way valve is configured to selectively and alternatively move to a fourth position that communicates fuel vapor between the internal combustion engine, the vapor management device and the carbon canister. A first vapor line is connected between the vapor management device and the three-way valve. A second vapor line is connected between the three-way valve and the carbon canister. A third vapor line is connected between the three-way valve and the internal combustion engine.

[0009] A method of managing fuel vapor flow in a fuel tank that stores and delivers fuel to an internal combustion engine is provided. A vapor management device, a carbon canister and a three-way valve are provided. The vapor management device has a fuel vapor generator that is configured to selectively generate fuel vapor is provided. The carbon canister is adapted to collect fuel vapor emitted by the fuel tank. The three-way valve selectively connects the vapor management device with the internal combustion engine and the carbon canister. An operating condition from the fuel tank is determined. Based on the operating condition, the three-way valve is positioned in one of a first and second position. In the first position, the three-way valve communicates the fuel vapor from the vapor management device to the internal combustion engine. In the second position, the three-way valve communicates the fuel vapor from the vapor management device to the carbon canister. In one example, determining the operating condition from the fuel tank includes determining at least one of a tank pressure, a canister pressure and a tank temperature. The three-way valve can further be positioned in a third position wherein the three-way valve communicates fuel vapor between the internal combustion engine and the carbon canister. The three-way valve can further be positioned in a fourth position wherein the three-way valve communicates fuel vapor between the internal combustion engine, the vapor management device and the carbon canister.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein: [0011] FIG. 1 is a schematic illustration of a fuel tank system having an evaporative emissions control system including a vent shut-off assembly, a controller, an electrical connector and associated wiring in accordance to one example of the present disclosure;

[0012] FIG. 2 is a front perspective view of an evaporative emissions control system including a vent shut-off assembly configured with solenoids according to one example of the present disclosure;

[0013] FIG. 3 is an exploded view of the evaporative emissions control system of FIG. 2;

[0014] FIG. 4 is a perspective view of a fuel tank system having a vent shut-off assembly and configured for use on a saddle fuel tank according to another example of the present disclosure and shown with the fuel tank in section view;

[0015] FIG. 5 is a perspective view of the vent shut-off assembly of the fuel tank system of FIG. 4;

[0016] FIG. 6 is a top perspective view of a vent shut-off assembly constructed in accordance to additional features of the present disclosure;

[0017] FIG. 7 is a bottom perspective view of the vent shut-off assembly of FIG. 6;

[0018] FIG. 8 is a sectional view of the vent shut-off assembly of FIG. 6 taken along lines 8-8;

[0019] FIG. 9 is a sectional view of the vent shut-off assembly of FIG. 6 taken along lines 9-9;

[0020] FIG. 10 is a front perspective view of a vent shut-off assembly constructed in accordance to another example of the present disclosure;

[0021] FIG. 1 1 is a sectional view of the vent shut-off assembly of FIG. 10 taken along lines 11 -1 1 ;

[0022] FIG. 12 is a sectional view of the vent shut-off assembly of FIG. 10 taken along lines 12-12;

[0023] FIG. 13 is an exploded view of the vent shut-off assembly of FIG. 10; and

[0024] FIG. 14 is a vapor management system having a vapor management device including a fuel vapor generator and a three-way valve according to another example of the present disclosure. DETAILED DESCRIPTION

[0025] With initial reference to FIG. 1 , a fuel tank system constructed in accordance to one example of the present disclosure is shown and generally identified at reference number 1010. The fuel tank system 1010 can generally include a fuel tank 1012 configured as a reservoir for holding fuel to be supplied to an internal combustion engine via a fuel delivery system, which includes a fuel pump 1014. The fuel pump 1014 can be configured to deliver fuel through a fuel supply line 1016 to a vehicle engine. An evaporative emissions control system 1020 can be configured to recapture and recycle the emitted fuel vapor. As will become appreciated from the following discussion, the evaporative emissions control system 1020 provides an electronically controlled module that manages the complete evaporative system for a vehicle.

[0026] The evaporative emissions control system 1020 provides a universal design for all regions and all fuels. In this regard, the requirement of unique components needed to satisfy regional regulations may be avoided. Instead, software may be adjusted to satisfy wide-ranging applications. In this regard, no unique components need to be revalidated saving time and cost. A common architecture may be used across vehicle lines. Conventional mechanical in-tank valves may be replaced. As discussed herein, the evaporative control system 1020 may also be compatible with pressurized systems including those associated with hybrid powertrain vehicles.

[0027] The evaporative emissions control system 1020 includes a vent shut-off assembly 1022, a manifold assembly 1024, a liquid trap 1026, a control module 1030, a purge canister 1032, an energy storage device 1034, a first vapor tube 1040, a second vapor tube 1042, an electrical connector 1044, a fuel delivery module (FDM) flange 1046 and a float level sensor assembly 1048. The first vapor tube 1040 can terminate at a vent opening 1041 A that may include a baffle arranged at a top corner of the fuel tank 1012. Similarly, the second vapor tube 1042 can terminate at a vent opening 1041 B that may include a baffle arranged at a top corner of the fuel tank 1012.

[0028] In one example, the manifold assembly 1024 can include a manifold body 1049 (FIG. 3) that routes venting to an appropriate vent tube 1040 and 1042 (or other vent tubes) based on operating conditions. As will become appreciated from the following discussion, the vent shut-off assembly 1022 can take many forms such as electrical systems including solenoids and mechanical systems including DC motor actuated cam systems.

[0029] Turning now to FIGS. 2 and 3, a vent shut-off assembly 1022A constructed in accordance to one example of the present disclosure is shown. As can be appreciated, the vent shut-off assembly 1022A can be used as part of an evaporative emissions control system 1020 in the fuel tank system 1010 described above with respect to FIG. 1. The vent shut-off assembly 1022A includes two pair of solenoid banks 1050A and 1050B. The first solenoid bank 1050A includes first and second solenoids 1052A and 1052B. The second solenoid bank 1050B includes third and fourth solenoids 1052C and 1052D.

[0030] The first and second solenoids 1052A and 1052B can be fluidly connected to the vapor tube 1040. The third and fourth solenoids 1052C and 1052D can be fluidly connected to the vapor tube 1042. The control module 1030 can be adapted to regulate the operation of the first, second, third and fourth solenoids 1052A, 1052B, 1052C and 1052D to selectively open and close pathways in the manifold assembly 1024, in order to provide over-pressure and vacuum relief for the fuel tank 1012. The evaporative emissions control assembly 1020 can additionally comprise a pump 1054, such as a venturi pump and a safety rollover valve 1056. A conventional sending unit 1058 is also shown.

[0031] The control module 1030 can further include or receive inputs from system sensors, collectively referred to at reference 1060. The system sensors 1060 can include a tank pressure sensor 1060A that senses a pressure of the fuel tank 1012, a canister pressure sensor 1060B that senses a pressure of the canister 1032, a temperature sensor 1060C that senses a temperature within the fuel tank 1012, a tank pressure sensor 1060D that senses a pressure in the fuel tank 1012 and a vehicle grade sensor and or vehicle accelerometer 1060E that measures a grade and/or acceleration of the vehicle. It will be appreciated that while the system sensors 1060 are shown as a group, that they may be located all around the fuel tank system 1010.

[0032] The control module 1030 can additionally include fill level signal reading processing, fuel pressure driver module functionality and be compatible for two-way communications with a vehicle electronic control module (not specifically shown). The vent shut-off assembly 1022 and manifold assembly 1024 can be configured to control a flow of fuel vapor between the fuel tank 1012 and the purge canister 1032. The purge canister 1032 adapted to collect fuel vapor emitted by the fuel tank 1012 and to subsequently release the fuel vapor to the engine. The control module 1030 can also be configured to regulate the operation of evaporative emissions control system 1020 in order to recapture and recycle the emitted fuel vapor. The float level sensor assembly 1048 can provide fill level indications to the control module 1030.

[0033] When the evaporative emissions control system 1020 is configured with the vent shut-off assembly 1022A, the control module 1030 can close individual solenoids 1052A-1052D or any combination of solenoids 1052A-1052D to vent the fuel tank system 1010. For example, the solenoid 1052A can be actuated to close the vent 1040 when the float level sensor assembly 1048 provides a signal indicative of a full fuel level state. While the control module 1030 is shown in the figures generally remotely located relative to the solenoid banks 1050A and 1050B, the control module 1030 may be located elsewhere in the evaporative emissions control system 1020 such as adjacent the canister 1032 for example.

[0034] With continued reference to FIGS. 1 -3, additional features of the evaporative emissions control system 1020 will be described. In one configuration, the vent tubes 1040 and 1042 can be secured to the fuel tank 1012 with clips. The inner diameter of the vent tubes 1040 and 1042 can be 3-4mm. In some examples, the poppet valve assembly or cam lobes will determine smaller orifice sizes. The vent tubes 1040 and 1042 can be routed to high points of the fuel tank 1012. In other examples, external lines and tubes may additionally or alternatively be utilized. In such examples, the external lines are connected through the tank wall using suitable connectors such as, but not limited to, welded nipple and push-through connectors.

[0035] As identified above, the evaporative emissions control system 1020 can replace conventional fuel tank systems that require mechanical components including in-tank valves with an electronically controlled module that manages the complete evaporative system for a vehicle. In this regard, some components that may be eliminated using the evaporative emissions control system 1020 of the instant disclosure can include in-tank valves such as GW's and FLW's, canister vent valve solenoid and associated wiring, tank pressure sensors and associated wiring, fuel pump driver module and associated wiring, fuel pump module electrical connector and associated wiring, and vapor management valve(s) (system dependent). These eliminated components are replaced by the control module 1030, vent shut-off assembly 1022, manifold 1024, solenoid banks 1050A, 1050B and associated electrical connector 1044. Various other components may be modified to accommodate the evaporative emissions control system 1020 including the fuel tank 1012. For example, the fuel tank 1012 may be modified to eliminate valves and internal lines to pick-up points. The flange of the FDM 1046 may be modified to accommodate other components such as the control module 1030 and/or the electrical connector 1044. In other configurations, the fresh air line of the canister 1032 and a dust box may be modified. In one example, the fresh air line of the canister 1032 and the dust box may be connected to the control module 1030.

[0036] Turning now to FIGS. 4 and 5, a fuel tank system 1010A constructed in accordance to another example of the present disclosure will be described. Unless otherwise described, the fuel tank system 101 OA can include an evaporative emissions control system 1020A that incorporate features described above with respect to the fuel tank system 1010. The fuel tank system 101 OA is incorporated on a saddle type fuel tank 1012A. A vent shut-off assembly 1022A1 can include a single actuator 1070 that communicates with a manifold 1024A to control opening and closing of three or more vent point inlets. In the example shown, the manifold assembly 1024A routs to a first vent 1040A, a second vent line 1042A and a third vent line 1044A. A vent 1046A routs to the canister (see canister 1032, FIG. 1 ). A liquid trap and a drain 1054A are incorporated on the manifold assembly 1024A. The fuel tank system 101 OA can perform fuel tank isolation for high pressure hybrid applications without requiring a fuel tank isolation valve (FTIV). Further, the evaporative emissions control system 1020A can achieve the highest possible shut- off at the vent points. The system is not inhibited by conventional mechanical valve shut-off or reopening configurations. Vapor space and overall tank height may be reduced.

[0037] Turning now to FIGS. 6-7, a vent shut-off assembly 1022B constructed in accordance to another example of the present disclosure will be described. The vent shut-off assembly 1022B includes a main housing 1 102 that at least partially houses an actuator assembly 1 1 10. A canister vent line 1 1 12 routs to the canister (see canister 1032, FIG. 1 ). The actuator assembly 1 1 10 can generally be used in place of the solenoids described above to open and close selected vent lines. The vent shut-off assembly 1022B includes a cam assembly 1 130. The cam assembly 1 130 includes a cam shaft 1 132 that includes cams 1 134, 1136 and 1138. The cam shaft 1 132 is rotatably driven by a motor 1 140. In the example shown the motor 1 140 is a direct current motor that rotates a worm gear 1 142 that in turn drives a drive gear 1 144. The motor 1 140 is mounted outboard of the main housing 1 102. Other configurations are contemplated. The cams 1 134, 1 136 and 1 138 rotate to open and close valves 1154, 1 156 and 1 158, respectively. The valves 1 154, 1 156 and 1 158 open and close to selectively deliver vapor through ports 1 164, 1 166 and 1 168, respectively. In one example the motor 1 140 can alternately be a stepper motor. In other configurations, a dedicated DC motor may be used for each valve. Each DC motor may have a home function. The DC motors can include a stepper motor, a bidirectional motor, a uni-directional motor a brushed motor and a brushless motor. The home function can include a hard stop, electrical or software implementation, trip switches, hard stop (cam shaft), a potentiometer and a rheostat.

[0038] In one configuration the ports 1 164 and 1 166 can be routed to the front and back of the fuel tank 1012. The port 1 164 can be configured solely as a refueling port. In operation, if the vehicle is parked on a grade where the port 1 166 is routed to a low position in the fuel tank 1012, the cam 1 134 is rotated to a position to close the port 1 164. During refueling, the valve 1 154 associated with port 1 164 is opened by the cam 1 134. Once the fuel level sensor 1048 reaches a predetermined level corresponding to a "Fill" position, the controller 1030 will close the valve 1 154. In other configurations, the cam 1 134, valve 1 154 and port 1 164 can be eliminated leaving two cams 1136 and 1 138 that open and close valves 1 156 and 1158. In such an example, the two ports 1 168 and 1 166 can be 7.5mm orifices. If both ports 1 168 and 1 166 are open, refueling can occur. If less flow is required, a cam position can be attained where one of the valves 1 156 and 1 158 are not opened all the way.

[0039] Turning now to FIGS. 10-13, a vent shut-off assembly 1022C constructed in accordance to another example of the present disclosure will be described. The vent shut-off assembly 1022C includes a main housing 1202 that at least partially houses an actuator assembly 1210. A canister vent line 1212 routs to the canister (see canister 1032, FIG. 1 ). The actuator assembly 1210 can generally be used in place of the solenoids described above to open and close selected vent lines. The vent shut-off assembly 1022C includes a cam assembly 1230. The cam assembly 1230 includes a cam shaft 1232 that includes cams 1234, 1236 and 1238. The cam shaft 1232 is rotatably driven by a motor 1240. In the example shown the motor 1240 is received in the housing 1202. The motor 1240 is a direct current motor that rotates a worm gear 1242 that in turn drives a drive gear 1244. Other configurations are contemplated. The cams 1234, 1236 and 1238 rotate to open and close valves 1254, 1256 and 1258, respectively. The valves 1254, 1256 and 1258 open and close to selectively deliver vapor through ports 1264, 1266 and 1268, respectively. In one example the motor 1240 can alternately be a stepper motor. A drain 1270 can be provided on the housing 1202.

[0040] In one configuration the ports 1264 and 1266 can be routed to the front and back of the fuel tank 1012. The port 1264 can be configured solely as a refueling port. In operation, if the vehicle is parked on a grade where the port 1266 is routed to a low position in the fuel tank 1012, the cam 1236 is rotated to a position to close the port 1266. During refueling, the valve 1254 associated with port 1264 is opened by the cam 1234. Once the fuel level sensor 1048 reaches a predetermined level corresponding to a "Fill" position, the controller 1030 will close the valve 1254. In other configurations, the cam 1234, valve 1254 and port 1264 can be eliminated leaving two cams 1236 and 1238 that open and close valves 1256 and 1258. In such an example, the two ports 1268 and 1266 can be 7.5mm orifices. If both ports 1268 and 1266 are open, refueling can occur. If less flow is required, a cam position can be attained where one of the valves 1256 and 1258 are not opened all the way.

[0041] FIG. 14 illustrates a vapor management system constructed in accordance to additional features of the present disclosure and generally identified at reference 1310. The vapor management system 1310 is configured for use on a fuel tank 1312 and generally includes a vapor management device 1314 that is selectively fluidly connected to a three-way valve 1320 through a first vapor line 1322. The three-way valve 1320 has a first port 1320a, a second port 1320b and a third port 1320c. The three-way valve 1320 is selectively fluidly connected to a carbon or purge canister 1324 through a second vapor line 1326. A third vapor line 1330 selectively connects the three way valve 1320 to an internal combustion engine 1334. The vapor management system 1310 can be used alone or in combination with evaporative emissions control system 1020 discussed above. The vapor management device 1314 can include a controller, or the vapor management device 1314 can communicate with a controller such as the controller 1030 (FIG. 1).

[0042] There are situations where it can be desirable to deliver fuel vapor from the fuel tank 1312 to the engine 1334 in a controlled or metered method. These situations can include specific control of the evaporative emissions purge strategy, a need to manage the fuel tank pressure (such as in a hybrid electric or PHEV system with a pressurized tank), or in a system designed to inject and burn fuel vapor as opposed to liquid gasoline. In any of these situations, there can be a need to control the fuel vapor present in the fuel tank 1312 and deliver it to the engine or carbon canister 1324 on demand. Additionally, there could be a need to generate vapors in the fuel tank 1312 under specific conditions.

[0043] The three-way valve 1320 can operate in a first position where the first vapor line 1322 is open to the third vapor line 1330 but closed to the second vapor line 1326. In the first position, the first and third ports 1320a and 1320c are open and the second port 1320b is closed. In the first position, the fuel tank 1312 vents to the internal combustion engine 1334.

[0044] In a second position, the first vapor line 1322 is open to the second vapor line 1326 but closed to the third vapor line 1330. In the second position, the first and second ports 1320a and 1320b are open and the third port 1320c is closed. In the second position, the fuel tank 1312 vents to the canister 1324.

[0045] In a third position, the second vapor line 1326 is open to the third vapor line 1330 but closed to the first vapor line 1322. In the third position, the second and third ports are open and the first port 1320a is closed. In the third position, the internal combustion engine 1330 vents to the canister 1324.

[0046] In a fourth position, all three of the first, second and third vapor lines 1322, 1326 and 1330 are open to each other. In the fourth position, the first, second and third ports 1320a, 1320b and 1320c are open.

[0047] The three-way valve 1320 manages vapor flow in the fuel tank 1312 by directing it to the internal combustion engine 1334 or to the canister 1324. It is further possible to manage the engine purge flow to pull from the fuel tank 1312, from the canister 1324 or from both. By using sensors in the fuel system, such as any combinations of the tank pressure sensor 1060A, the canister pressure sensor 1060B, the temperature sensor 1060C and the vehicle accelerometer 1060E (FIG. 1 ), the engine controller 1030 can determine the optimal conditions for purge and manage the flow of vapor to the engine 1334. In this regard, a method is provided to precisely maintain pressure inside the fuel tank 1312 at a specified level, as well as control the amount of vapor sent to the carbon canister 1324 for storage. This can help reduce the evaporative emissions of the fuel system as a whole.

[0048] In one example, a vapor generator 1350 can be provided in the vapor management device 1314 to generate fuel vapor through the heating and/or agitation of the liquid fuel. The vapor generator 1350 can be a motor, a fuel pump (such as the fuel pump 1014 FIG. 1 ), or other device capable of creating fuel vapor from liquid fuel. The vapor management system 1310 can create vapor to deliver to the engine 1334 during specific conditions where vapor can be most efficiently burned during the combustion cycle.

[0049] The foregoing description of the examples has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular example are generally not limited to that particular example, but, where applicable, are interchangeable and can be used in a selected example, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Claims

CLAIMS What is claimed is:

1. A vapor management system configured for use with a fuel tank that stores and delivers fuel to an internal combustion engine, the vapor management system comprising:

a vapor management device having a fuel vapor generator; a carbon canister adapted to collect fuel vapor emitted by the fuel tank; a three-way valve that selectively connects the vapor management device with the internal combustion engine and the carbon canister; and

wherein the fuel vapor generator is configured to selectively generate fuel vapor, the three-way valve configured to open to a position that communicates the fuel vapor from the vapor management device to the internal combustion engine.

2. The vapor management system of clam 1 , further comprising a first vapor line connected between the vapor management device and the three-way valve.

3. The vapor management system of claim 2, further comprising a second vapor line connected between the three-way valve and the carbon canister.

4. The vapor management system of claim 3, further comprising a third vapor line connected between the three-way valve and the internal combustion engine.

5. The vapor management system of claim 4 wherein the three-way valve operates in a first position where the first vapor line is open to the third vapor line but closed to the second vapor line.

6. The vapor management system of claim 5 wherein the three-way valve operates in a second position where the first vapor line is open to the second vapor line but closed to the third vapor line.

7. The vapor management system of claim 6 wherein the three-way valve operates in a third position where the second vapor line is open to the third vapor line but closed to the first vapor line.

8. The vapor management system of claim 7 wherein the three-way valve operates in a fourth position where the first, second and third vapor lines are all open to each other.

9. The vapor management system of claim 1 wherein the vapor generator is a motor.

10. The vapor management system of claim 1 wherein the vapor generator is a fuel pump.

1 1. A vapor management system configured for use with a fuel tank that stores and delivers fuel to an internal combustion engine, the vapor management system comprising:

a vapor management device having a fuel vapor generator that is configured to selectively generate fuel vapor;

a carbon canister adapted to collect fuel vapor emitted by the fuel tank; a three-way valve that selectively connects the vapor management device with the internal combustion engine and the carbon canister;

wherein the three-way valve is configured to selectively and alternatively move to (i) a first position that communicates the fuel vapor from the vapor management device to the internal combustion engine; and (ii) a second position that communicates the fuel vapor from the vapor management device to the carbon canister.

12. The vapor management system of claim 1 1 wherein the three-way valve is configured to selectively and alternatively move to (iii) a third position that communicates fuel vapor between the internal combustion engine and the carbon canister.

13. The vapor management system of claim 12 wherein the three-way valve is configured to selectively and alternatively move to (iv) a fourth position that communicates fuel vapor between the internal combustion engine, the vapor management device, and the carbon canister.

14. The vapor management system of clam 1 1 , further comprising a first vapor line connected between the vapor management device and the three-way valve.

15. The vapor management system of claim 14, further comprising a second vapor line connected between the three-way valve and the carbon canister.

16. The vapor management system of claim 15, further comprising a third vapor line connected between the three-way valve and the internal combustion engine.

17. A method of managing fuel vapor flow in a fuel tank that stores and delivers fuel to an internal combustion engine, the method comprising:

providing a vapor management device having a fuel vapor generator that is configured to selectively generate fuel vapor;

providing a carbon canister adapted to collect fuel vapor emitted by the fuel tank;

providing a three-way valve that selectively connects the vapor management device with the internal combustion engine and the carbon canister;

determining an operating condition from the fuel tank;

based on the operating condition, positioning the three-way valve in one of (i) a first position that communicates the fuel vapor from the vapor management device to the internal combustion engine; and (ii) a second position that communicates the fuel vapor from the vapor management device to the carbon canister.

18. The method of claim 17 wherein determining an operating condition from the fuel tank comprises determining at least one of a tank pressure, a canister pressure and a tank temperature.

19. The method of claim 17 wherein positioning the three-way valve further comprises selectively and alternatively positioning the three-way valve in (iii) a third position that communicates fuel vapor between the internal combustion engine and the carbon canister.

20. The method of claim 19 wherein positioning the three-way valve further comprises selectively and alternatively positioning the three-way valve in (iv) a fourth position that communicates fuel vapor between the internal combustion engine, the vapor management device, and the carbon canister.