Field

[001 ] This application relates to fuel valves and provides an in-line valve with over-pressure and over-vacuum relief functions.

Background

[002] Fuel valves typically have complicated housings and assembly processes. Many require angles to accommodate the various components. Angle flow valves can suffer from undesired pressure changes because of angles necessary to accommodate the various components and port requirements. The bulkiness of angle valves make them more difficult to control and to find space for in a system.

SUMMARY

[003] The methods and devices disclosed herein overcome the above

disadvantages and improves the art by way of an in-line valve.

[004] An in-line valve comprises a solenoid assembly comprising a hollow tubular pole piece, a bobbin, a coil, and flux collection plates. A cylindrical armature is within the pole piece, the armature comprising a hollow central passageway and a step in the hollow central passageway. A spring is in the central passageway and a seal is seated against the spring to bias the seal against the step.

[005] A method for controlling the in-line valve comprises selectively powering the solenoid assembly to move the armature between a sealed position, where a second seal blocks a port, to an open position, where the armature moves away from the port.

[006] Additional objects and advantages will be set forth in part in the

description which follows, and in part will be obvious from the description, or may be learned by practice of the disclosure. The objects and advantages will also be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.

[007] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the claimed invention. BRIEF DESCRIPTION OF THE DRAWINGS

[008] Figure 1 is a cross-section view of an in-line valve.

[009] Figure 2 is a cross-section of another in-line valve.

[010] Figure 3 is a cross-section of another in-line valve.

[01 1 ] Figure 4 is a cross-section of another in-line valve.

[012] Figure 5 is a cross-section of another in-line valve.

[013] Figure 6 is a view of an armature and seal.

[014] Figure 7 A & 7B are views of an armature and seals.

[015] Figure 8 is a view of solenoid sleeve.

[016] Figure 9 is a flow diagram of a pulse control method.

DETAILED DESCRIPTION

[017] Reference will now be made in detail to the examples which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. Directional references such as "left" and "right" are for ease of reference to the figures.

[018] By eliminating angled flow paths, pressure differential across the valve is more easily tailored by port diameter changes. Assembly is less complicated and the footprint of the valve is reduced. Optional encapsulation strategies reduce leak paths and reduce the number and extent of seals. An in-line valve offers high flow, small package, single stage pulsed de-pressurization, low cost, and calibrated set points.

[019] A first example of an in-line valve, shown in Figure 1 , comprises a solenoid assembly 100 comprising a hollow tubular pole piece 1 10, a pole piece 160, a bobbin 120, a coil 125, and flux collection plates 130, 131. The solenoid assembly surrounds valve components, which more effectively utilizes the space inside the solenoid and yields a more compact assembly. By crafting the pole pieces 1 10 and 160 to extend along the bobbin 120, o rings 430 and 530 efficiently restrict leak paths within the device. Fluid can be coupled from valve port 400 to valve port 500 with minimal sealing mechanisms, resulting in material and size savings. In some embodiments, pole piece 1 10 is integrated with the valve port 500 as a unitary member, and pole piece 160 is integrated with valve port 400 as a unitary member. The integration eliminates yet another leak path and another need for sealing mechanisms. The port connections can be, for example, press-fit, quick-connect, snap fit, or barbed end.

[020] In yet other embodiments, pole pieces 1 10 and 160 are over molded and surrounded by an encapsulating housing 800. The valve ports 400 and 500 are unitary with the encapsulating housing 800. Leak path elimination can be augmented by using a bonding agent, locking feature, tortious flow path, geometry or a combination thereof between the over mold and pole pieces 1 10 & 160. If needed, the augmentation can also be applied to the flux collectors, such that the over molding is applied to contact or surround portions of the flux collectors, the flux collectors including the bonding agent, locking feature, tortious flow path, geometry, etc. A tortious flow path permits inflow of molding material in to a gap, and this can reduce valve weight by removing metal from the flux collector and or pole piece and then filling it with a lighter weight molding material. The port connections can be, for example, press-fit, quick-connect, snap fit, or barbed end are integrated to the solenoid assembly via the over molding.

[021 ] The pole pieces 1 10 & 160 can be a magnetic material, for example, a 400 series stainless steel or a low carbon steel. They can be plated to protect against corrosion. The pole pieces can be stamped or formed. Armature 200 is attracted to pole piece 160 when the coil 125 is energized. Figures 3 and 5 illustrate the activated condition, whereby armature 200 overcomes the spring force of armature spring 300. Wiring and power supply connections for the solenoid can be provisioned and molded with the encapsulating housing 800.

[022] Because material use impacts weight, durability, and actuation power, among other things, it is possible to use a magnetic material for only one of the pole pieces 1 10 & 160. For example, for Figures 3-5, it is possible to use a magnetic material for pole piece 160 so that armature is attracted to it when the solenoid is activated.

However, pole piece 160 can be a different material, such as brass or bronze or another material. The spring force of armature spring 300 biases the armature 200 towards pole piece 1 10 when the solenoid is deactivated. However, in Figures 1 & 2, pole piece 1 10 can be a magnetic material to attract armature 200 when the solenoid is activated. The pole piece 1 10 can also integrated with a first of the flux collection plates 130. Spring 300 biases armature 200 towards flux collector 131 when the solenoid is deactivated. Flux collector 131 can include an extension piece 1310 that extends along armature 200. Or, like Figures 3-5, pole piece 1 10 can include an extension piece 1 100 to guide armature 200. External ridges 216 can abut the extension piece 1310 or 1 100 by extending outward from armature body 292 at angles.

[023] In the alternative, a space exists between the pole pieces 1 10 and 160. The space can receive a guide tube 320. The pole piece 1 10 extends within the solenoid assembly 100 to guide the armature 200 via an extension piece. The guide tube adjoins the extension piece of the pole piece, and the second pole piece 160 adjoins the guide tube 320. Guide tube 320 can be non-magnetic. A bearing material like brass or bronze can be used. Or, the guide 320 tube can be plastic and molded as part of bobbin 120. The guide tube acts as a secondary bearing for the armature 200. The guide tube can have crush features on one or both ends that can be deformed to keep the valve assembly loaded together. Thus, the guide tube 320 can maintain a component dimensional stack up that is the same as the standoff length.

[024] A cylindrical armature 200 is seated within the pole piece 1 10. The armature 200 comprises a hollow central passageway 210 and a step 245 in the hollow central passageway 210. The step 245 seats a seal, which can be an over pressure or over vacuum relief seal. The seal can be a disc 270 seated in a piston 275, as shown in Figure 1 , or a ball 260, as shown in Figure 3. The ball 260 can be elastomeric and can be used with the structure of Figure 1 or Figure 3. As shown in Figure 6, the step 240 can be part of a central constriction in the armature 200.

[025] A spring 250 in the central passageway 210 biases the seal, ball 260 or disc 270. An over vacuum or over pressure condition can oppose spring forces of the spring 250 and lift the seal from the step 240 or 245. The spring 250 can be retained, as shown in Figure 1 , by an adjustment feature 213 such as a retaining ring, crimp ring, rolled ring, or slip or press fit tube. The adjustment feature permits calibration of the spring and thus the seal. An internal notch 212 can receive the retaining ring 213. The spring 250 can seat against the ball 260, disc 270, or piston 275.

[026] Alternatively, as shown in Figure 3-5, a spring seat 280 in the central passageway 210 seats the valve spring 250 to bias the seal 260 towards the step 240.

[027] A second seal 600 on the first end 201 of the armature 200 can be held in place via a lip 603 that catches in gland 203. The second seal 600 can be formed to completely seal fluid passage between valve ports 400 and 500. Or, the second seal can comprise an orifice 605 that permits a predetermined amount of fluid to bleed through the second seal 600.

[028] The armature 200 is fluted by comprising external ridges 216. The ridging forms fluid passageways between the pole piece 1 10 and the armature 200 to permit a high rate of fluid flow. Radial gaps 204 exist around the center line X of the armature 200, and between the center line X of the armature and the surrounding solenoid components, because the external ridges 2016 are spaced circumferentially around the center line X of the armature. The armature 200 can have slots 206 to permit fluid flow from the hollow central passageway 210 to in between the external ridges 216. Or, the armature can comprise a solid body 292 to fluidly separate central passageway 210 from the radial gaps 204.

[029] Hybridization is possible to shape the magnetic force-stroke curve. Solid angular face 290, shown in Figures 6B & 7A, provides an uninterrupted conical pole surface, which increases the pole area to acquire magnetic force compared to the clawlike extended ends 212 of Figure 6A. The seal 600 is more supported by the increased contact surface. Also, the inner diameter of the angular face provides a tailorable vapor flow path. The flow path can continue through the solid body 292 of Figures 7A& 7B, or fluid flow can extend through slots 206 radially distributed on the armature 200. Slots 206 between external ridges 216 permit fluid flow between external ridges 216 or within central passageway 210. Provisioning slots 206, or not, permits flow restriction tailoring. The external ridges 216 can be sized to abut the inner circumference of the pole pieces 1 10, 160, and guide tube 320 when present.

[030] The fluted armature enables fluid flow in-line. No turns or angles are needed in the flow path in order to implement the solenoid control. In this way, the valve design is simplified in to a central carriage. The armature is assembled and customized and is a central carrier loaded in to the solenoid assembly. Fluid can flow easily around the external ridges 216 when the armature is positioned for that flow path, as by activating or deactivating the solenoid, or as by slots 206 in body 292. The hollow central passageway 210 within the armature provides another fluid passageway. The central passageway 210 can be sized to restrict flow, as shown in the constricted area near step 240 in Figure 3. Thus, diameter changes can be used for controlling pressure differential across the in-line valve.

[031 ] The armature 200 comprises a first end 201 and a second end 202. In Figures 3-6, the external ridges 216 extend on the second end of the armature 200, and the extended ends 212 of the external ridges 216 have angled faces 290 to align with an angled valve seat 412 affiliated with valve port 400. When second seal 600 is mounted to the extended ends 212, the second seal 600 seals against the angled valve seat 412. Second seal can adhere to extended ends 212, or be held in place by armature spring 300, or catch in seat 214. As above, the second seal 600 can be contiguous to completely seal fluid flow between valve ports 400 & 500, or an orifice 605 can be included to permit a predetermined amount of fluid bleed-through. Thus, second seal 600, among the others, can be tailored to a desired metering function, such as relieving a fluid pressure along a pressure decay curve.

[032] Armature 200 can be biased away from valve port 400 in several ways. In one way, the distal ends of the extremal ridges 216 are stepped to form a spring seat 214 for biasing the armature spring 300 away from the valve port 400. The spring seat 214 can be located between the extended ends 212 and the second end 202 as necessary for the spring force. The valve port 400 can comprise a spring step 410 for receiving the other end of armature spring 300. Or, armature spring 300 can bias against pole piece 1 10 or flux collection plate 130. Armature spring 300 can bias against steps in external ridges 216, Or, armature spring 300 can bias against a seal 600 or 610 seated on one of the ends 201 , 202.

[033] The in-line valve can comprise a third seal 610 affixed to a neck 220 on the second end 202. The neck 220 can surround an armature hole 230, the armature hole 230 permitting vapor flow through the central passageway 210 and through an optional orifice 615 in the third seal 610. The third seal 610 can comprise a lip 613 to catch on the second end 202. The second end can alternatively comprise a gland to mate with the lip 613. An armature spring 330 can abut the pole piece 1 10 and the second end 202 to bias the armature away from valve port 500 and towards valve port 400. This can bias the second seal 600 against valve port 400.

[034] Third seal 610 can seal against a seat 1 15 of pole piece 1 10 to block fluid flow to valve port 500. In other embodiments, third seal 610 can seal against a seat 132 of the flux collection plate.

[035] The solenoid assembly can be configured to move the armature 200 among a sealed position, where the second seal 600 blocks valve port 400, to an open position, where the armature 200 is centered in the solenoid assembly, to a metered position, where the third seal 610 meters fluid flow at valve port 500.

[036] The solenoid assembly can be further configured to move the armature 200 from a sealed position, where the second seal 600 blocks valve port 400, to an open position, where the armature is centered in the solenoid assembly 100.

[037] One feature of the in-line valve assembly is that it can be oriented in either direction, tank to canister, based on spring force and seal strength, so that the seal can be configured to relieve an over pressure condition from the tank, or to relieve an over vacuum condition in the tank. By selecting among the number and size of the alternative seals 260, 270, 600 and 610 valve functionality and performance can be controlled. [038] A method for controlling the in-line valve comprises powering the solenoid assembly to move the armature 200 between a sealed position, where the second seal 600 blocks valve port 400, to an open position, where the armature is centered in the solenoid assembly, to a metered position, where the third seal 610 meters fluid flow at a second port.

[039] A method for controlling the in-line valve can comprise selectively powering the solenoid assembly to move the armature 200 between a sealed position, where the second seal 600 blocks valve port 400, to an open position, where the armature moves away from the valve port 400.

[040] The solenoid assembly can be selectively powered according to a pressure decay function.

[041 ] In Figure 3, the armature 200 is shown energized by the solenoid assembly 100. Alternatively, a vacuum condition in the tank can unseat armature 200. Seal 260 is, for example, configured for over pressure relief (OPR) and the second seal 600 is configured for over vacuum relief (OVR). When the armature 200 moves from port 500 towards port 400, vapors from the tank flow to the canister. When the solenoid assembly is de-energized, the armature spring 300 pushes the armature 200 toward the port 500. Second seal 600 abuts port 500. If an over-vacuum occurs in the tank, the armature spring 300 is overcome by the vacuum, and seal 600 unseats to alleviate the vacuum. If an excess pressure from the tank occurs, seal 260 unseats. Vapor flows through the central passageway 210 and through an orifice in second seal 610.

[042] Reversing the in-line valve, as shown in Figure 4, and adjusting the spring forces, shows the valve in an de-energized state. Fluid flows from the tank to the canister when the solenoid is energized or when an over pressure in the fuel tank moves armature 200 away from port 500. By including an orifice 615 in seal 610, an over-vacuum can act to unseat seal 240.

[043] In Figures 3 and 4, the ports 400 and 500 cooperate to position the armature 200, and at least one port extends in to the solenoid assembly to form the pole piece. Thus, the pole piece is integrated into the port end. The ports 400, 500 can be a metal such as a magnetic stainless steel. While shown with fluid port connection hubs, it is possible to form a more cost effective version, with truncated port necks 520, 420 at both sides of the solenoid, as shown in Figure 5. The entire solenoid could be over- molded and the port connections included as part of the over-mold, as shown in Figure 5. Attachment ports 810 are likewise included with the over-mold. [044] Figures 1 -5 benefit from an additional adjustment feature. In Figures 1 and 2, a retaining ring is modifiable to adjust the spring force, as by adjusting the width of the retaining ring. In lieu of a snap ring 213 in an internal notch 21 1 , illustrated, a press- fit can be used. This is shown in Figures 3 and 4, where spring seat 280 is pressed in to the armature to adjust spring tension.

[045] Figures 1 -5 permit a pulse-control method to meter fuel vapor. The valve is pulsed periodically to control vapor pressure in the tank. This permits quick re-fueling, because the vapor pressure never exceeds a predetermined amount during vehicle operation. And, make-up air is permitted entry to the tank during the pulsing. When the valve is unpowered, safety mechanisms, in the form of the seals 260, 270 or 600, permit necessary over pressure and over vacuum relief.

[046] For example, in Figure 9, fluid bleeds through armature 200 in step S900. This bleed can be through seal 600. As shown in Figure 4, it is possible to permit fluid bleed through the external ridges 216 without using seal 600, as by slotting body 292 or using extended ends 212 in a "claw" configuration. As shown in Figure 4, it is possible to bleed through orifice 615 in seal 610. Relief air, or tank fluid such as fuel vapors, can bleed through armature 200. The diameter of the seals, and presence or absence of orifices is based on fluid dynamics and pressure control.

[047] A sensor determines if fluid pressure in a tank, such as fuel in a fuel tank, is above a predetermined threshold in step S902. If not, fluid pressure continues to bleed through armature 200. If tank pressure is above the threshold, the process moves to step S904 to pulse the solenoid power to unseat the armature 200. The pulsing can be according to a pressure decay function. The pressure decay function can permit fine metering, as described, or complete depressurization of the tank, such as for refueling the tank. The solenoid control can be done to prevent upstream corking of other valves. When the tank pressure is below the predetermined threshold, as determined in step S906, the process returns to step S900, as by unpowering the solenoid. Otherwise, return to step S904 continues solenoid control to shuttle armature 200 as needed between seated , intermediate, and unseated positions. Returning to a seated position during pulsing permits fine metering, as by controlling a small "slug" of fluid.

[048] A pulse control method prevents corking of other valves in the system by finely controlling the vapor pressure. Users require quick depressurization to ensure the fuel tank is safe to fill by the time the driver reaches the tank to open it. While it is possible to use a two stage valve and orifice to control depressurization, the pulse control method eliminates the need for a second stage valve. An on/off style valve could give too much vapor flow during a fuel fill event, which would cork the fill unit vent valve and disrupt overfill protection of the fuel tank. If such a refueling valve reseats, instead of the needed full vapor flow, no flow is permitted, and the fuel fill event is hampered.

[049] In a vehicle application, pulsing the in-line valve during ordinary operation maintains a selectable pressure range in the tank. During refueling, additional pressure can be released for safe refueling. This reduces the time to reach a safe refueling pressure. Instead of actuating two valves, or two stages, only one valve is actuated. The internal geometry of the in-line valve eliminates a valve and its affiliated spring, which results in cost, material, and space savings. By pulsing the armature according to the decay of pressure, it is possible to maintain a very low pressure drop during refueling, which avoids corking of other valves.

[050] By reducing material use, as by eliminating o-rings a lower solenoid power can be used. Further weight reductions are possible by implementing a perforated sleeve 140, shown in Figure 8. For example, over-mold material can be lighter than traditional solenoid can materials, and can be lighter than seals. When using sleeve 140, it is possible to include perforations 1400. The perforations 1400 can permit ingress of molding fluid in to air gap 150. The molding fluid can thus create a chemical barrier and protect the solenoid from corrosion. The molding fluid can leak in to other gaps at pole pieces 1 10, 160 and flux collection plates 130, 131 and create fluid leak path sealing upon curing the molding fluid.

[051 ] For sleeve 1400, a sheet material can be, for example, stamped and roll- formed. The sleeve can be attached to the solenoid assembly by, for example, crimping or joinery techniques such as the illustrated dove-tail tab 1404 in notch 1402.

Extensions 1 144 can be included to catch against flux collection plates 130, 131 or pole pieces 1 10, 160. Spaces between the extensions 144 permit wiring for the solenoid to pass through the sleeve 140. The low material use and elegant design of the in-line valve permits lower solenoid power, resulting in a smaller coil assembly and smaller over-all valve. While circular perforations 1400 are shown, other shapes, such as square, oval, rectangular, crenelated, etc. are possible.

[052] Tailoring the pressure drop across the valve is also possible by tailoring the size and extent of the external ridges 216 on the armature. The size and extent of the external ridges 216 impact the space for fluid flow. By sizing the external ridges 216 and second and third seals 600, 610, it is also possible to size a "slug" of fluid. A small volume of fluid that fits in gap 204 can thus be shuttled within the valve, permitting a fine control over the amount of air pulsed out of the valve. By controlling the diameter of the armature body 292, which in figures 7 & 8 is solid, by controlling the diameter of central passageway 210, and by controlling the diameter of seal orifices 605, 610, fluid pressure differentials from valve port 400 to valve port 500 can also be tailored. 290

[053] With the third seal 610 of Figure 1 , the pulse control method can be more complex to include a metering function. A finer mass resolution is achieved by partially blocking flow to the port 500 or by designing the third seal 610 to provide full port blockage. While it is possible to use a voltage driven solenoid assembly for armature control in Figures 1 -4, it is possible to use a current driven solenoid assembly for Figure 1 to facilitate the finer control.

[054] Fine control in the pulse control method is possible because the in-line valve is easier to actuate than an angle valve. The in-line valve can have its stroke length tailored more precisely. Thus, the armature 200 can be moved between a full right, a middle, and a full left position, with resulting blocking and unblocking of the ports 400 and 500.

[055] Figures 1 & 4 show the in-line valve at rest (de-energized). Figure 2 shows the armature in a centered (partially lifted) condition. Figures 3 and 5 show the armature 200 in an energized condition with the solenoid assembly 100 powered and the armature spring 300 spring force overcome.

[056] The in-line valve has a smaller foot-print than angle-flow valves because the valve components are within the solenoid assembly. Angle-flow valves stack the solenoid over the valve components and need additional material to create the port bends for the angles. The in-line valve is more compact because of the stackable nature of the ports to the flux collectors.

[057] Various packaging configurations are available, and features of each can be combined with features of the others. In Figures 1 and 2, a sleeve 140 creates electrical connectivity between the flux plates 130, 131 . No air gap exists between the sleeve 140 and the coil 125, though one can be included, as in Figure 5. The sleeve 140 includes fingers 144 bent around the ends of the solenoid assembly. The fingers 144 clamp extensions 402, 502 of the valve ports against the flux collection plates 130, 131. The flux collection plates 130, 131 are stacked against the bobbin 120. The configuration is a highly efficient drop-in and stacking assembly technique. Few leak paths exist, and minimal o-rings 430, 435, 530, 535 are needed. [058] In Figures 3 and 4, and alternative drop-in assembly is shown. The valve ports 400, 500 are integrated with the pole pieces 160, 1 10. This eliminates o-rings 435 & 535. O-rings 530 & 430 remain to seal the pole pieces 1 10, 160 against the bobbin 120. With the internal leak path efficiently sealed, the flux collection plates 131 , 130 can abut the sleeve without additional sealing, though a bonding agent or seal can be used. Flux collection plate 131 press-fits to sleeve 140 to clamp integrated valve port 400 and pole piece 160 in the assembly. An air gap 150 can be between sleeve 140 and coil 125. While a lip 146 is shown in Figure 3, it is possible to also crimp the valve port 500 using fingers 144, as in Figure 4. Also, tabs 148 can be supplied on sleeve 140 for crimping the flux collection plate 131 , or for valve mounting or purposes.

[059] Figure 5 shows an efficiently packaged and low-leak in-line valve. The pole pieces 160, 1 10 are truncated and do not form the valve ports 400, 500. Instead, necks 420, 520 are included for permitting press-fitting of the flux collection plates 131 , 130 to the pole pieces. The sleeve 140 does not include fingers or lips, but does abut the flux collection plates 131 , 130. Sleeve 140 can be stamped or roll-formed. It can be a solid sheet material, so as to maintain air gap 150 with air. Sleeve can alternatively be slotted, meshed, or otherwise punctured to have openings to permit ingress of encapsulation material in to the air gap 150. The ingress of encapsulation material seals leak paths and provides more adherence of the encapsulating housing 800 to the components. Encapsulating housing 800 integrally forms the valve ports 400, 500 and attachment port 810. Attachment port 810 can be, for example, an electrical wiring port for powering the solenoid (wiring omitted for clarity), or can be a mounting expedient, such as a catch, clip, foot, screw-hole or like mounting mechanism. A bonding agent, or other attachment augmentation means, can be applied to the pole pieces 160, 1 10, flux collection plates 131 , 130, and sleeve 140 as needed to assist with connectivity and leak path sealing.

[060] When over-molding in the manner of Figure 5, it is important to preserve the integrity of the pressure relief. Material selection must prevent leak-in of the selected material and spoilage of the seals. Tortuous pathways can be used to preserve the integrity of the in-line valve.

[061 ] The encapsulation methods shown permit flexibility in meeting customer requirements. A central carriage can be assembled. The armature can be customized with seals 270, 260, 610, 600, with or without orifices 615, 605. Armature spring 300 size and force can be selected. The armature is assembled using simple drop-in techniques, and the carriage is assembled by inserting the armature in to the solenoid assembly. The carriage can be oriented for over pressure or over vacuum relief capabilities. Port connection type and attachment ports 810 are selected easily in the molding crib. Die lock is avoided by eliminating turns. Necking up or necking down can be achieved using tooling connected to form ports 400 & 500. Encapsulating as a final assembly step thus presents great advantages.

[062] Other implementations will be apparent to those skilled in the art from consideration of the specification and practice of the examples disclosed herein.