Self sufficient suction side automatic drain valve

Various example embodiments relate to an automatic drain system for use with a fluid water separator. The automatic drain system includes a liquid-in-fuel sensor configured to detect a liquid level in a water sump. A pump includes an inlet in fluid communication with the water sump and an outlet in fluid communication with the inlet. The pump has an active state and an inactive state. The active state causes the pump to draw liquid in from the inlet and direct liquid toward the outlet. A battery is configured to power the pump. A circuit board is operably connected to the pump and battery. The circuit board includes at least one circuit having a first state and a second state. The first state prevents power flow from the battery to the pump. The second state facilitates power flow from the battery to the pump, transitioning the pump from inactive to active.

FIELD

The present application relates generally to fuel water separator filter systems.

BACKGROUND

Fuel water separator filters that filter fuel, for example diesel fuel, and also separate water from the fuel before the fuel is passed to the engine are known. Various fuel water separator filter constructions are described in, for example, U.S. Pat. Nos. 7,857,974 and 7,935,255. When the water level rises to a certain level within the fuel water separator filter (e.g., fuel filter assembly), the water may carried by the fuel into the rest of the fuel system (e.g., into the fuel injectors), which causes damage to the fuel system and/or the engine system. Periodic draining of the water that is separated from the fuel by the fuel water separator filter is therefore generally required.

SUMMARY

Various example embodiments relate to an automatic drain system for use with a fluid water separator. The automatic drain system includes a liquid in-fuel sensor configured to detect a liquid level in a water sump. A pump includes an inlet in fluid communication with the water sump and an outlet in fluid communication with the inlet. The pump has an active state and an inactive state. The active state causes the pump to draw liquid in from the inlet and direct liquid toward the outlet. A battery is configured to power the pump. A circuit board is operably connected to the pump and the battery. The circuit board includes at least one circuit having a first state and a second state. The first state prevents power flow from the battery to the pump. The second state facilitates power flow from the battery to the pump. Detection of the liquid level by the liquid-in-fuel sensor causes the circuit board to transition from the first state to the second state, thereby causing the pump to transition from the inactive state to the active state.

Other example embodiments relate to a filtration system. The filtration system includes a filter housing defining an internal volume. The filter housing includes a housing first end and a housing second end positioned axially away from the housing first end. A filter element is positioned within the internal volume. The filter element includes a first endplate, a second endplate positioned axially away from the first endplate, and filter media extending from the first endplate toward the second endplate. The first endplate includes a liquid drain port that places the filter element in fluid communication with a water sump. The water sump is positioned at the housing first end. An automatic drain system coupled to the water sump. The automatic drain system includes a liquid in-fuel sensor configured to detect a liquid level in a water sump. A pump includes an inlet in fluid communication with the water sump and an outlet in fluid communication with the inlet. The pump has an active state and an inactive state. The active state causes the pump to draw liquid in from the inlet and direct liquid toward the outlet. A battery is configured to power the pump. A circuit board is operably connected to the pump and the battery. The circuit board includes at least one circuit having a first state and a second state. The first state prevents power flow from the battery to the pump. The second state facilitates power flow from the battery to the pump. Detection of the liquid level by the liquid-in-fuel sensor causes the circuit board to transition from the first state to the second state, thereby causing the pump to transition from the inactive state to the active state.

Additional example embodiments relate to a method of draining a water sump of a filtration system using an automatic drain system. The method includes passing a mixture through a filter media. The mixture includes water and a fuel. The filter media extends between a first endplate and a second endplate of a filter element. The second endplate is positioned axially away from the first endplate. The first endplate includes a liquid drain port that places the filter element in fluid communication with a water sump. The filter element is positioned within an internal volume of a filter housing. The filter housing includes a housing first end and a housing second end positioned axially away from the housing first end. Water from the mixture is captured and coalesced. The coalesced water passes through the liquid drain port into the water sump positioned at the housing first end. The water is in contact with a liquid-in-fuel sensor of an automatic drain system coupled to the water sump. The automatic drain system includes a liquid in-fuel sensor configured to detect a liquid level in a water sump. A pump includes an inlet in fluid communication with the water sump and an outlet in fluid communication with the inlet. The pump has an active state and an inactive state. The active state causes the pump to draw liquid in from the inlet and direct liquid toward the outlet. A battery is configured to power the pump. A circuit board is operably connected to the pump and the battery. The circuit board includes at least one circuit having a first state and a second state. The first state prevents power flow from the battery to the pump. A liquid level is detected by the liquid-in-fuel sensor. The circuit board transitions from the first state to the second state, thereby causing the pump to transition from the inactive state to the active state. The coalesced water is drained from the water sump.

DETAILED DESCRIPTION

FWS filter systems (and filter systems generally) require the periodic draining of water that has been removed from the fuel and stored in a water sump. An FWS filter system may include a fuel pump, an FWS filter element, and a filter housing including a water sump. The failure to drain the separated water from the water sump may result in system failures, resulting in attendant repair and maintenance costs. The automatic drain systems described herein operate independently of user control to drain the water from an FWS. Such systems thus remove the possibility that a user's failure to drain the water from an FWS system may result in increased maintenance and repair costs. Specifically, the automatic drain system is structured to monitor collected liquid levels in the liquid collection sump, or similar structure, in a filter housing. The automatic drain system may be implemented on the suction side of the FWS filter system and is configured to drain (e.g., remove water) when the engine is stopped (e.g. not active), thereby allowing the automatic drain system to drain water under atmospheric pressure and before the engine is active. The removal of the collected liquid will prevent the collected liquid from entering the fuel stream and damaging downstream the fuel delivery components or the engine. Beneficially, the automatic drain system includes a compact and self-sufficient (e.g., battery) design that does not require the use of solenoid valves, complicated wiring, or excessive space. The automatic drain system may further provide a safe canister or plumbing to facilitate temporary storage of drained liquids. In some embodiments, the design of the automatic drain system produces a substantially constant mass flow rate of liquid from the FWS, through the automatic drain system, and out of the FWS.

As utilized herein, a “high pressure side” refers to the side of the fuel pump from which fuel flows, while a “suction side” refers to the side of the fuel pump to which fuel is supplied. The pressure differential between the sides of the FWS filter system provides the motive force that drives the water and fuel mixture through the FWS filter system.

Turning toFIG.1, an FWS filter system100with an automatic drain system150is shown, according to an example embodiment. The FWS filter system100includes a filter element104disposed within a filter housing102. The FWS filter system100is located on a suction side of a fuel pump. The automatic drain system150is coupled to the filter housing102and is in fluid communication with a liquid drain port108of the filter element104.

The FWS filter system100may be structured to separate two immiscible phases of a mixture (e.g., fuel or lubricant and water) into a continuous phase (e.g., herein referred to as “fuel”) and a dispersed phase (herein referred to as “liquid”). As the mixture passes through the filter element104, the dispersed phase is captured and coalesced. The liquid falls along the filter housing102, in the direction of gravity, and axially enters a liquid collection sump106disposed below the filter housing102. In some embodiments, the FWS filter system100comprises an inside-out coalescing filter element104, however, in other embodiments, the FWS filter system100comprises an outside-in coalescing filter element104.

The filter housing102defines an internal volume within which the filter element104is positioned. The filter housing102may be formed from a strong and rigid material, for example plastics (e.g., polypropylene, high density polyethylene, polyvinyl chloride, etc.), metals (e.g., aluminum, stainless steel, etc.), or any other suitable material. In particular embodiments, the filter housing102may comprise a cylindrical housing having generally a circular cross-sectional. In other embodiments, the filter housing102may have any suitable shape, for example square, rectangular, polygonal, etc.

The filter housing102comprises a housing first end110and a housing second end extending axially away from the housing first end110. The housing first end110includes at least one male thread112provided on an inner surface thereof. In some arrangements, the at least one male thread112is stamped into the filter housing102. In other arrangements, the at least one male thread112may be molded or otherwise formed into a sidewall of the filter housing102.

As shown inFIG.1, the filter element104includes an endplate114and filter media116. In some arrangements, the filter element104is a cylindrical filter element. The endplate114includes a liquid drain port108that places the filter element104in fluid communication with the liquid collection sump106. The liquid drain port108may include a seal member (e.g., O-ring or other resilient seal) between the automatic drain system150and the filter housing102. A seal member may be provided to ensure a fluid tight seal is formed between the automatic drain system150and the filter housing102. In some embodiments, at least one air vent is also provided in the filter housing102to allow air to be communicated from the interior portion of the automatic drain system150to the FWS filter system100.

The filter media116is structured to separate two immiscible phases of a mixture into liquid and fuel or lubricant. Accordingly, as the mixture passes through the filter media116, the liquid is captured and coalesced by the filter media116. The coalesced liquid falls along the inside of the filter element104, in the direction of gravity, to the liquid collection sump106under the filter housing102. The liquid remains disposed in the liquid collection sump106unless the liquid level exceeds an amount that causes the liquid to enter the flow stream. Beneficially, the automatic drain system150is configured to prevent the liquid level from reaching a level that causes the liquid to enter the flow stream.

The automatic drain system150includes the liquid collection sump106, a liquid-in-fuel sensor (e.g., a water-in-fuel (“WIF”) sensor118), an automatic drain valve120, and a check valve122. The liquid collection sump106is positioned at the housing first end110, and includes a female thread124structured to engage the male thread112of the filter housing102so as to be coupled to the housing first end110. The liquid collection sump106forms an internal cavity126that is in fluid communication with the liquid drain port108of the filter element104to receive the coalesced liquid from the FWS filter system100. In some embodiments, the liquid collection sump106is a part of and/or formed with the filter housing102and is configured to receive the automatic drain system150. In other words, the automatic drain system150is installed into the liquid collection sump106.

Turning toFIG.2, an exploded view of an automatic drain system150is shown, according to an example embodiment. The automatic drain system150includes the WIF sensor118, the check valve122, the liquid collection sump106, and the automatic drain valve120. Generally, the automatic drain system150is structured to monitor collected liquid levels in the liquid collection sump106through the WIF sensor118. The automatic drain valve120is configured to facilitate the removal of the collected liquid from the liquid collection sump106, thereby preventing the collected liquid from entering the fuel stream and damaging downstream the fuel delivery components or the engine. The automatic drain system150may further provide a safe canister or plumbing to facilitate temporary storage of drained liquids. As shown inFIG.1, the automatic drain valve120is located at the base of the liquid collection sump106and protrudes through a sump opening128into the internal cavity126of the liquid collection sump106. As will be appreciated, the automatic drain system150may protrude into the liquid collection sump106in order to accurately monitor the liquid level.

The WIF sensor118is configured to monitor the liquid level within the internal cavity126of the liquid collection sump106. A wide variety of WIF sensors and/or liquid level sensors may be implemented with the automatic drain system150to monitor liquid level and/or trigger the pump210. The check valve122is configured to prevent placing the pump210under suction.

The liquid collection sump106includes the sump opening128to receive the protruding element218of the automatic drain valve120. In some embodiments, the protruding element218includes a seal member226configured to form a seal between the protruding element218and sump opening128. As shown below inFIG.3D, the liquid collection sump106includes a liquid outlet330and may include at least one sump drain opening. As shown inFIG.2, the liquid collection sump106includes a plurality of ribs230disposed axially along an external surface of the liquid collection sump106. The plurality of ribs230are configured to facilitate the removal and installation of the liquid collection sump106(e.g., grips). In some arrangements, the liquid collection sump106may be formed from at least one of a translucent or a transparent material, for example, thin plastic, plexiglass, acrylic, etc. The transparent, substantially transparent or translucent liquid collection sump106may allow a user to visually observe if water or any other contaminants are accumulated in the liquid collection sump106. In other arrangements, the liquid collection sump106may be formed from an opaque material, such as plastic or metal.

The automatic drain valve120includes a pump210, a battery216, and a circuit board204disposed within an automatic drain valve housing202. The automatic drain valve housing202includes a protruding element218, a pump inlet222, a first pump outlet212, a second pump outlet214, and a plurality of engagement elements224. In some embodiments, the circuit board204may include a controller.

The circuit board204includes a sensing element220disposed within a protruding element218of the automatic drain valve housing202. The sensing element220is operably connected and/or in communication with the WIF sensor118such that when the WIF sensor118identifies a liquid level or is at a liquid level, the sensing element220is triggered. The circuit board204is configured to activate when the liquid in the liquid collection sump reaches a level that requires draining (e.g., “desired sump capacity”). In other words, the desired sump capacity level is the liquid level of the collected liquid for which it is preferred to drain the liquid collection sump106to avoid the collected liquid from entering the fuel stream and damaging the engine or components downstream. In some embodiments, the desired sump capacity is between 40% and 70% of the capacity of the liquid collection sump106, for example, at 60% of the capacity of the liquid collection sump106. Once activated, the circuit board204may be configured to convert direct current (“DC”) power of a battery216into alternating current (“AC”) current with high voltage to drive a pump210. In some embodiments, the circuit board204may pass DC power of the battery216to the pump210, in other embodiments, the circuit board may pass AC power of the battery216to the pump210, and in some embodiments, the circuit board204may convert AC power of the battery216to DC power to drive the pump210.

The pump210is configured to receive power from the battery216by way of the circuit board204. The pump210is configured to be a low power consumption such that the battery216is sufficient to efficiently and effectively run the pump210. The pump210is configured to drain liquid from the internal cavity126of the liquid collection sump106through the liquid outlet330. A check valve may be disposed between the pump210and the liquid outlet330to allow for pumping in one direction (e.g., out of the liquid collection sump106). The pump210is in fluid communication with the first pump outlet212and the second pump outlet214. In some embodiments, a check valve may be disposed in one or both of the first pump outlet212and the second pump outlet214to prevent subjecting the pump210to a vacuum.

Referring toFIG.3A, a cross-sectional perspective view of an automatic drain system150is shown, according to an example embodiment. The WIF sensor118is configured to monitor if the liquid level in the liquid collection sump106reaches a desired sump capacity level and is configured to trigger the sensing element220. As shown inFIG.3A, the WIF sensor118includes a float element302(e.g., float valve) and a magnetic element304. The float element302is configured to have a density that causes the float element to float in water but sink in diesel or similar fluid. The float element302may be disk-shaped. The magnetic element304is configured to “activate” or “trigger” the sensing element220. As shown inFIG.3A, the magnetic element304is coupled to the float element302at a position associated with the desired sump capacity so that the magnetic element304will be adjacent to or near enough to the sensing element220to trigger it. The magnetic element304may be coupled to an external top, bottom, or side surface of the float element, disposed in an external cavity of the float element302or disposed internally of the float element302. As will be appreciated, once the engine is off and the vehicle is stationary, water will separate from the fuel and cause the float element302to rise. Once the float element302rises to the desired sump capacity level (e.g., a first position) the magnetic element304will activate the sensing element220. Once an amount of liquid has been removed, the float element302will drop below the desired sump capacity level (e.g., a second position) and the magnetic element304will no longer activate the sensing element220. In some embodiments, the magnetic element304comprises a material, apparatus, or activating element that forms a wireless (e.g., non-wired) connection, bridge, or communication with the sensing element220.

The sensing element220is disposed internal of the protruding element218and extends into the internal cavity126of the liquid collection sump106. The sensing element220includes a magnetic switch310that is configured to be activated by the magnetic element304on the float element302at a specific height associated with the desired sump capacity level. For example, in some embodiments, the magnetic element304of the WIF sensor118is raised by the liquid accumulating within the liquid collection sump106to the desired sump capacity level at which point the magnetic switch310is activated bridging a circuit402(e.g., of the circuit board204) between the battery216and the pump210, thereby activating the pump210. The automatic drain system150will then drain the liquid collection sump106under atmospheric pressure. In some embodiments, the sensing element220includes a second switch that triggers the deactivation of the pump210(e.g., breaks the bridge). In other embodiments, the circuit board204, pump210, and/or battery216are configured to operate for a specified time.

While the WIF sensor118is shown as a float-magnet sensor, a wide variety of WIF sensor configurations may be implemented with the automatic drain system150. In some embodiments, the WIF sensor118includes an upper WIF sensor and a lower WIF sensor, where the detection of liquid by the upper WIF sensor indicates that the liquid level in the liquid collection sump106has reached a level where draining is required and the absence of liquid by the lower WIF sensor may the pump to stop operation, thereby completing the draining process. In the absence of a lower WIF sensor, a timed release may be implemented with a predetermined open time calculated from a timer algorithm of a predetermined liquid density and quantity of typical precipitate/liquid. In other embodiments, the WIF sensor118or other sensors may be similar to the sensors described in U.S. Pat. No. 10,031,098, issued Jul. 24, 2018 and the contents of which are incorporated by reference in its entirety. The WIF sensor118or other sensors can comprise a sensor tube that includes tube wires that extend through a connection block and the resistance of the tube segment above the fluid level is infinite because the air between the tube wires acts as an insulator. Accordingly, the higher the fluid level, the less resistance between the tube wires, and thereby the lower the voltage at a DC voltmeter. In some embodiments, the water-in-fuel sensor118also comprises an electronic coupler structured to allow communicative coupling of the water-in-fuel sensor118and the circuit board204.

As shown inFIG.3B, the pump210is in fluid communication with the internal cavity126of the liquid collection sump106through the pump inlet222. The pump inlet222extends from a surface of the automatic drain valve housing202. Once the circuit402is closed (e.g., the magnetic element304triggers or closes the magnetic switch310) power will flow from the battery216, through the circuit board204, and to the pump210. Once active, the pump210draws liquid from the internal cavity126, through the pump inlet222, and through the first pump outlet212and/or the second pump outlet214. The first pump outlet212and/or the second pump outlet214may be in fluid configuration with a tank, secondary container, or outside of the FWS filter system100. Any one of the pump inlet222, first pump outlet212, and second pump outlet214may include a check valve along each respective flow path. As will be appreciated, a check valve along the pump inlet222prevents placing the pump210under suction. A check valve along the first pump outlet212or second pump outlet214facilitates pumping in one direction.

A pump cycle350of the pump210is shown inFIG.3C. The pump210may cycle between an active state that causes the pump210to draw liquid in from the pump inlet222and direct liquid toward the first pump outlet212or second pump outlet214when the circuit402is closed and provides power.

The pump cycle350may include blocking one or more openings in the liquid collection sump106, alternating the suction in one or more openings in the liquid collection sump106, or having a check valve disposed in fluid communication with one or more openings in the liquid collection sump106to prevent back flow. In some embodiments, the pump210is a positive piezoelectric pump.

Referring toFIG.3D, a bottom perspective view of the automatic drain system150ofFIG.3Ais shown. In some embodiments, the liquid collection sump106may include an engagement opening332that is configured to secure the automatic drain valve120to the liquid collection sump106. As shown inFIG.3D, the battery216is a disc or coin-shaped battery. The battery216is configured to supply enough power to operate the pump210for the desired period of time.

FIGS.4A and4Bare perspective views of the automatic drain valve120. Beneficially, the automatic drain valve120may be a self-contained self-sufficient unit. In such embodiments, the automatic drain valve120may not include any external wires or connections with a wiring harness. Additionally, the automatic drain valve120may need to be interfaced with an ECU or other control system to properly and automatically drain the FWS filter system100. This independent nature of the automatic drain valve120allows the automatic drain valve120to be employed with both electronically controlled and mechanically controlled engine systems. In some embodiments, the automatic drain valve120may be retrofitted onto a pre-existing FWS filter system100.

FIG.4Cshows a cross-sectional view of the automatic drain valve ofFIG.4Aincluding the magnetic switch310that, when activated by the magnetic element304closes and/or branches the circuit402. As shown, the protruding element218extending axially away from a top surface of the automatic drain valve housing202. The pump inlet222may be disposed laterally away from the protruding element218, over the pump210, and extends axially upward away from the pump210. The first pump outlet212may be disposed opposite of the second pump outlet214. Both the first pump outlet212and the second pump outlet214may extend away from a side surface of the automatic drain valve housing202.