Motor and Pump System with Fluid Level Control Plate

This application claims priority to U.S. Provisional Application 63/641,564, filed May 2, 2024, which is incorporated herein by reference in its entirety.

The present disclosure is generally related to a pump assembly/system including a pump, a motor and a controller, which has a control plate therein for controlling a level of lubricant such that cooling of the controller is effectively maintained.

The oil or fluid in pumps may be used to provide cooling to parts of an assembly, including an associated controller. In some cases, hollow shafts may be utilized in order to route oil/fluid for cooling. U.S. Pat. No. 11,821,420 B2 to Graves et al., which is incorporated herein in its entirety, shows an electric oil pump with a hollow shaft, drawing fluid through the hollow shaft of the inlet port of the pump on the motor side. However, maintaining and controlling a level of oil in a motor cavity are generally not known in such a configuration.

In designs where the axis of the pump is installed in a generally horizontal orientation, the height of the oil level in the motor cavity is dictated by wherever the return port within the cavity is located, which in the known prior art is typically fixed in the housing structure between the pump and the motor cavity, or in some designs the oil (or other liquid) is returned through the shaft rather than being delivered through the shaft. If the flow return is through the shaft, then at best the fill level when the pump stops operating can only be at the height of the shaft (which is typically about halfway up, i.e., 50%). If the flow return is through a port fixed in a housing part, then the fill level can only go to the height of that return port. Thus, a housing part designed with a return port has the shortcoming that the installation orientation dictates the height of the fill level. In order to ensure a high fill level, which is beneficial as then the motor cavity is already “primed” in that it starts off with a high volume of lubricant or other liquid so it can be cooled by circulation quickly, the pump system must be installed with the return port at the height of the desired fill level. The inventors have recognized that this can be problematic in designing a pump system to accommodate different packaging constraints and orientations, or customer specification updates requiring orientation changes. This is particularly the case because relocation of the return port is not simply a matter of just changing the location of the return port in the housing. The return port typically is located at the low pressure/suction side of the pump (also called the inlet side) and thus reorientation of the pump may also be required, which in turn may affect other parts and conduits used to establish fluid communication from the pump inlet and outlet to the high pressure and low pressure areas of the pump itself. The inventors have recognized that this makes designing a pump system that is flexible in terms of orientations due to packaging constraints, particularly those in a vehicle environment where space is often highly constrained by other parts in the vehicle, challenging and costly.

It is an aspect of this disclosure to provide a pump system for installation in a generally horizontal orientation including: a housing with a pump for pumping a liquid and an electric motor therein; a pump inlet with a pump inlet port; a pump outlet with a pump outlet port; a drive shaft rotatably driven by the electric motor, for driving the pump to pressurize fluid received through a fluid path of the pump from the pump inlet for output to the pump outlet; an intermediate housing wall positioned between the pump and the electric motor and covering a motor cavity within the housing for the electric motor; and an auxiliary circuit configured to direct a portion of fluid flow to the motor cavity. The intermediate housing wall has a pump inlet return port for directing the fluid flow from the motor cavity to the pump. A fill level control plate is positioned between the intermediate housing wall and the motor cavity, forming an overflow region between the intermediate housing wall and the fill level control plate. The fill level control plate includes an overflow opening therethrough for directing fluid flow from the motor cavity to the overflow region. The fill level control plate is installed with the overflow opening at a location spaced radially from the drive shaft for positioning substantially vertically above the drive shaft and the pump inlet return port when installed. The fill level control plate causes a liquid level within the motor cavity to rise during operation of the pump system and the auxiliary circuit has a return path through the electric motor for directing the portion of fluid flow for cooling the electric motor through the overflow opening in the fill level control plate and relatively down the overflow region, to return back to the pump via the pump inlet return port.

Another aspect of this disclosure includes a method of manufacturing a pump system configured for installation in a generally horizontal orientation. Such method includes: providing a housing, the housing having an intermediate housing wall; providing a pump and an electric motor, the pump having a pump inlet having a pump inlet port and a pump outlet having a pump outlet port; and providing a drive shaft to be rotatably driven by the electric motor, for driving the pump to pressurize fluid received through a fluid path of the pump from the pump inlet for output to the pump outlet. The method also includes positioning the pump and the electric motor within the housing; positioning the intermediate housing wall therebetween and covering a motor cavity within the housing for the electric motor; and installing a fill level control plate between the intermediate housing wall and the motor cavity, forming an overflow region between the intermediate housing wall and the fill level control plate. In the method, the pump system further includes an auxiliary circuit configured to direct a portion of fluid flow to the motor cavity; the intermediate housing wall has a pump inlet return port for directing the fluid flow from the motor cavity to the pump; and the fill level control plate has an overflow opening therethrough for directing fluid flow from the motor cavity to the overflow region. The installation of the fill level control plate includes positioning said overflow opening at a location spaced radially from the drive shaft for positioning substantially vertically above the drive shaft and the pump inlet return port when installed, such that the fill level control plate causes a liquid level within the motor cavity to rise during operation of the pump system and the auxiliary circuit has a return path through the electric motor for directing the portion of fluid flow for cooling the electric motor through the overflow opening in the fill level control plate and relatively down the overflow region, to return back to the pump via the pump inlet return port.

Yet another aspect of this disclosure includes a vehicle including: a device to receive liquid; and the above disclosed pump system coupled to the device to deliver the liquid thereto, wherein the pump system is installed with the overflow opening positioned substantially vertically above the drive shaft and the pump inlet return port.

Other aspects, features, and advantages of the present disclosure will become apparent from the following detailed description, the accompanying drawings, and the appended claims.

The description set forth below in connection with the appended drawings is intended as a description of various embodiments of the disclosed subject matter and is not necessarily intended to represent the only embodiment(s). In certain instances, the description includes specific details for the purpose of providing an understanding of the disclosed embodiment(s). However, it will be apparent to those skilled in the art that the disclosed embodiment(s) may be practiced without those specific details. In some instances, well-known structures and components may be shown in block diagram form in order to avoid obscuring the concepts of the disclosed subject matter.

Reference throughout the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrases “in one embodiment” or “in an embodiment” in various places throughout the specification is not necessarily referring to the same embodiment. Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments. Further, it is intended that embodiments of the disclosed subject matter cover modifications and variations thereof.

It is to be understood that terms such as “up,” “below,” “top,” “bottom,” “side,” “upper,” “lower,” “interior,” “exterior,” “inner,” “outer,” and the like that may be used herein merely describe points of reference and do not necessarily limit embodiments of the present disclosure to any particular orientation or configuration. Typically, such references will be to the orientation of the drawings for convenience of the reader. Furthermore, terms such as “first,” “second,” etc., merely identify one of a number of portions, components, steps, operations, functions, and/or points of reference as disclosed herein, and likewise do not necessarily limit embodiments of the present disclosure to any particular configuration or orientation, or any requirement that each number must be included or that they must be included in any particular order.

As understood by one of ordinary skill in the art, “pump displacement” or “displacement” as used throughout this disclosure refers to a volume of liquid or fluid (e.g., lubricant, oil) a pump is capable of moving during a specified period of time, i.e., a flow rate. For explanatory and simplicity purposes herein, the term “liquid” is utilized to reference fluid, lubricant, or oil that is pressurized and pumped by the pump in the disclosed system and provided to the motor cavity for cooling purposes; however, the terms may be used interchangeably throughout this disclosure.

As evident by the drawings and below description, the disclosed pump system and method of manufacturing the same includes an assembly having an intermediate housing wall positioned between a pump and an electric motor, covering a motor cavity within a housing for the electric motor, an auxiliary circuit configured to direct a portion of fluid flow to the motor cavity, and a fill level control plate is positioned between the intermediate housing wall and the motor cavity, forming an overflow region between the intermediate housing wall and the control plate. As a result, this disclosure provides more control over the distribution of fluid or liquid (e.g., oil) that is not only sent to auxiliary circuit but also enables more liquid to the motor cavity, e.g., for cooling purposes. In particular, no matter the orientation and/or mounting of the assembly, the disclosed system enables more liquid into the motor cavity, thereby avoiding failure of the motor and (optionally) the controller, e.g., due to overheating. This disclosure provides a desired level of fluid via using the fill level control plate which allows for shifting of a location for feeding liquid from the auxiliary circuit back to the pump, and further seals off points within the pump assembly.

In one non-limiting embodiment, the controller is a “wet” controller such that it is submerged with the motor in the motor cavity and in the liquid; as such, this liquid is configured to encompass the controller and its associated parts for cooling purposes as well. The controller may also be dry, but mounted on a structure that is in contact with the circulating liquid so that heat from the controller or parts thereof is exchanged through the structure to the circulating liquid. In other embodiments, the controller may be separate and cooled by other means.

The disclosed designs allow for temperature management of motors, and controllers (and any sensors), no matter the position or orientation of the system.

shows a schematic view of a pump systemor pump assembly in accordance with an embodiment herein, configured for installation in a generally horizontal orientation. Pump systemmay include an electronic pump, or e-pump, also referred to herein as simply a “pump” (shown in cross-sections in). The pumpis designed for pumping a liquid. In an embodiment, the pump systemis designed to provide power to actuate clutch or transmission.

In accordance with a non-limiting embodiment, pump systemmay be a system or assembly such as described in U.S. Pat. No. 10,808,697 (U.S. Ser. No.: 15/653,690) which is hereby incorporated by reference in its entirety herein, i.e., a pump assembly (or system) that has an assembly inlet for inputting fluid, an assembly outlet for outputting fluid, an electric motor contained within a motor casing, a pump having a pump housing, a drive shaft connecting the electric motor to the pump, and a controller configured to drive the electric motor. In such embodiment, the pump of the incorporated '697 application has an inlet for receiving input fluid from the assembly inlet and a transfer outlet for outputting pressurized fluid; the drive shaft is configured to be driven about an axis by the electric motor; and the pump and the electric motor are on opposing axial sides of the controller. The pump assembly of the incorporated '697 application also has a heat conductive plate positioned between the pump and the controller, for conducting heat from the controller; a transfer passage provided in the pump assembly for receiving the pressurized fluid output from the transfer outlet of the pump and directing the pressurized fluid along and in contact with the heat conductive plate to conduct heat therefrom into the pressurized fluid, and an outlet passage that communicates the transfer path with the assembly outlet to discharge the pressurized fluid. However, such assembly or system of the incorporated '697 application is not limiting. Another example for pump systemmay be a system or assembly such as described in U.S. application Ser. No. 15/653,690, which is also hereby incorporated by reference in its entirety herein. Other pump systems and/or features may be utilized.

Pump systemhas multiple structural sections that are connected to house or contain its parts therein, i.e., within a system housing, as shown in. In an embodiment, a pump housingis provided as part of the system housing, which includes the pumptherein. An outer portion of the pump housingmay be generally cylindrical according to an embodiment. The pump housingincludes a pump chamber, which, in embodiments, may be cylindrical, ovular, or circular, for receiving parts of the pumptherein (noted later below). The pump housinghas a pump inletfor receiving input fluid to direct said fluid to a pump inlet portB (generally shown in, see also) that is connected to an inlet pathA and a pump outletfor outputting pressurized fluid from a pump outlet portB (generally shown in, see also), e.g., via an outlet pathA. Specifically, in the depiction of, the inlet portB and outlet portB are provided on the same side (e.g., under or below the gear set) within the pump, in accordance with embodiments herein. A drive shaft(see, e.g.,) is provided for rotation about an axis A-A and rotatably driving parts of the pumpto pressurize the input fluid received through a fluid path-i.e., main path[from the inletfor the input fluid] (see), for outputting pressurized fluid, e.g., from outlet pathA to the pump outlet.

The type of pumpand its parts provided in the pump system/assemblyis not limited. In an embodiment, the pumphas a gerotor drive, wherein an inner rotor is rotatably driven by the drive shaftto in turn rotatably drive an outer rotor. A pump end of the shaftextends to (or through) a portion of the pump housing. The inner rotor is fixedly secured to the shaftfor rotation about axis A with the drive shaft. The outer rotor may be rotatably received in the pump chamberof the housing. In embodiments, the pump chamberand the outer surface of the outer rotor are cylindrical. A motor end of the drive shaftis positioned on an opposite side of an electric motor(described below). Although not shown, it is generally known that the drive shaftmay be supported, for example, by journal bearings within housing(s) of the pump system. As is understood by one of ordinary skill in the art, rotation of the inner rotor also rotates the outer rotor via their intermeshed teeth to pressurize the input fluid received in areas between the complimentary parts for output from the pump, and thus such details are not described here. In accordance with a non-limiting embodiment herein, the inner rotor and outer rotor are part of gerotor pump and configured for operation like that which is disclosed in the aforementioned and incorporated U.S. '697 Patent or the incorporated '690 application. In another non-limiting embodiment, the inner rotor and outer rotor are part of a gerotor pump and configured for operation like that which is disclosed in U.S. Pat. No. 5,722,815 (U.S. Ser. No.: 08/515,054) which is also incorporated by reference in its entirety herein.

Other types of pump parts for pressurizing input fluid may also be used in pump in accordance with other embodiments, including gear pumps, vane pumps, etc. and other types of positive displacement pumps, and thus pumpshould not be limited to gerotor-type pumps in pump system.

As generally understood by one skilled in the art, as the pumprotates—e.g., in an exemplary embodiment of a gerotor pump, as inner rotor is rotatably driven by drive shaft, to rotate/drive an outer rotor via their intermeshed teeth—fluid is pressurized in areas between the complimentary parts for output from the pump. Additionally, in embodiments, fluid may be pressurized within a displacement area or chamber between the rotors. As the rotors rotate, the area/chamber moves across the inlet portB and its lobes, as well as across the outlet portB and its lobes. Such movements and feature in pumpare known and thus are not described here in detail.

Pump systemalso includes electric motor(shown inand) for mechanical output and a motor drive shaft provided in system housing. In embodiments, the motor drive shaft and pump drive shaftare the same drive shaft, i.e., one singular shaft, that extends through and from the motorand through the pump. In another embodiment, the motor drive shaft and pump shaft are different parts. In the non-limiting illustrated embodiment, the electric motoris connected to the pumpvia the drive shaft, which is configured to be driven about axis A-A. The electric motoris configured to drive the drive shaftof the pumpvia the motor drive shaft, to rotatably drive parts of the pump, i.e., to pressurize the input fluid, and to cool the motor/traction system or other deviceusing the liquid as a coolant (or for whatever reason the device requires fluid, such as for lubrication, general liquid delivery, etc.). As understood by those skilled in the art, the motorincludes a motor rotorand a motor stator. The rotoris connected to the motor drive shaftand is contained within a motor casingalong with the stator. The motor casing(or motor housing) is part of the system housingand designed for connection to the pump housing. The motor casingmay be generally cylindrical and may include an inner motor cavityor portion thereof for housing the rotorand stator. The statormay be optionally fixed to the motor casing.

As will be described below, according to embodiments, the motor cavityis designed for receipt of liquid (e.g., oil) therein. A covermay be included as part of system housingto assist in enclosing the motor cavityand containing the liquid therein. In particular, as shown in the Figures, an opposite side or end of the motor casingmay include coverattached thereto for further containing at least the motor parts within and forming the motor cavity. The motor casingand covermay include alignment devices for aligning and securement. In embodiments, the covermay be welded (e.g., plastic welded) to the motor casing. An optional outer cover may be provided around cover; this outer cover may include one or more channels for allowing placement of terminals, wiring, etc. to a controller, for example, which is described later below.

An auxiliary circuitor auxiliary fluid path is included in pump system, as schematically shown in. Auxiliary circuitis configured to direct a portion (or percentage) of fluid flow to the motor cavityof motor casing, according to embodiments herein. In embodiments, fluid or liquid directed through the auxiliary circuitmay be directed to this circuit from the pump inletand/or deviate from the main pathof the pump. In an embodiment, the pumpuses negative pressure (suction), via a connection to the inlet port on the motor side of the pump, to draw the working fluid or liquid (e.g., oil) through a hollow shaft. In an embodiment, the auxiliary circuitincludes a path through an internal bore(see) in the drive shaft, for directing the portion of fluid flow into the motor cavityand a return path., which is described later, illustrates one exemplary embodiment showing the auxiliary circuitincludes a fluid passageway defined in, at, or near the inletof the pump that deviates from the main pathto direct lubricant to the motor cavityvia the drive shaft. In particular, the auxiliary circuitdirects fluid through a length of the drive shaftfor outlet to the return path. After flowing to the motor end of the drive shaft, lubricant is redirected to return pathwhich includes a pathway of return flow for motor cooling. The return pathmay include multiple pathways therein such that the fluid/lubricant is directed through a number of places of the motor parts, in the motor cavity. For example, the lubricant may be directed through multiple pathways through the rotor and stator componentsand, and across the motor, such as generally shown in. As described below, the return pathincludes redirecting a portion of flow of the liquid/fluid back to the pumpvia directing fluid to the motor cavity, to overflow region, and to return port.

In embodiments, the electric motormay be further contained within the system housingof the pump systemby a wall that separates the motor parts and parts of the pump. Specifically, according to embodiments herein, an intermediate housing wallis positioned between the pumpand the electric motor. The intermediate housing wallcovers motor cavityon one side or end of the motor casing/within the housing for the electric motor. The intermediate housing wallmay be provided against/adjacent to and connected to each of the pump housingas well as the motor casing. In an embodiment, the intermediate housing wallmay be a separate part. In another embodiment, the intermediate housing wallmay be formed integrally therewith the housingor casing. For example, openings(shown in) in the intermediate housing wallmay be spaced circumferentially around a lip of the walland aligned with corresponding openings on pump housing. Fastenersand/or bolts (shown in) may be inserted through the aligned openings to connect and secure the pump housingand intermediate housing wall. The intermediate housing wallmay have a first axial side (also referred to as the pump-facing side) of the intermediate housing wallthat faces the pump.shows a top view of the first side (pump side) of the intermediate housing wall, according to an embodiment. This first axial side of wallmay have one or more receiving recesses(see) formed therein which form part of inlet and outlet portsB,B of the pump. Each receiving recessprovided in the intermediate housing wallmay be in the form of an indentation that extends an axial depth from the surface and into the first axial side thereof. When the intermediate housing wallis secured against the pump housing, the inlet portB and outlet portB are formed in-between the recessand the rotor(s) of the pump(i.e., due to the depth of the recess extending into the wall(that is, in towards the motor side). As described previously, fluid is input via pump inlet, through the pathA, and into pump inlet portB, for pressurization by the pump parts. Pressurized fluid is directed from pump outlet portB towards the outlet pathA and outletA of the pump.

A second axial side (also referred to as the motor-facing side) of the intermediate housing wall, which is opposite to the first axial side, may include an extension walland one or more recessed regionstherein.shows a top view of this second side (motor side) of the intermediate housing wall, according to an embodiment. Extension walland region(s)face the electric motorwhen mounted, which is shown in the cross-section of, for example. In an embodiment, the extension wallis designed for insertion to the motor casingand sealing via an O-ring seal (e.g., press-fit) to enclose the motor cavity. Thus, the intermediate housing walleffectively acts as a cover for the pumpon the pump side and as a cover for the motor cavitywithin the system housingfor the electric motoron the motor side. The recessed region(s)within the intermediate housing wallare designed for holding a portion of fluid therein and providing a path for said portion of fluid from a level or amount of fluid within the motor cavityduring operation of the pump system(described later below with reference to overflow region). In addition, the drive shaftmay be configured to extend through an inner openingwithin the intermediate housing wall, according to embodiments. This inner openingmay be a central opening within the wall. In one embodiment, the intermediate housing wallmay have an alignment portionthat surrounds the inner openingand extends axially. Such an alignment portion may be provided for not only aligning the drive shafttherethrough, but also for aligning additional parts (e.g., a fill level control plate) within the system housing, as described later.

In embodiments, the intermediate housing wallhas a pump inlet return portfor directing the fluid flow of the liquid from the motor cavityto the pump(e.g., to the main pathof the pump, shown in the exemplary embodiment of).shows a top view of the second axial side (motor-facing side) of the intermediate housing wallwith the pump inlet return porttherein.shows a pump-side view of pump inlet return port, and how it communicates with the inlet portB of pump;shows a motor-side view of the placement of pump inlet return portwithin the wall. The pump inlet return portmay be an opening that extends axially and through a thickness of the wall.

Generally, providing an opening or return portfor directing fluid from the motor cavityto the pumpmay be known by those skilled in the art. However, because the pump systemmay be positioned in any number of orientations when mounted for use, e.g., as shown in the Figures in a horizontal configuration (or in a vertical configuration, angled configuration, etc.), then, a level of fluid within the motor cavity, and thus the motor casing, may be altered based on that configuration. As an example,shows an example of a pump system oriented and mounted horizontally, wherein the pump is configured to pressurize fluid (as known) and output the pressurized fluid through the outlet. An alternate flow pathA through a drive shaft is designed for directing fluid into a motor cavity thereof during operation. When using a return port to direct flow from the motor cavity to the pump in this orientation, however, a level of fluid within the motor cavity is not typically maintained, as depicted by the dashed line, in. That is, because the fluid moves through the motor cavity and to the pump through the opening or return, only a certain level atof fluid is typically maintained, and in some cases, the motor cavitywould not or does not fill with fluid based on the orientation of the return connection to the pump. If the connection (opening) to the pump is positioned at the bottom of the pump's installed orientation, the resulting oil level (e.g., level) in the motor cavity will be lower than if the return is positioned at the top. Understandably to one skilled in the art, then, when such a system is mounted generally horizontally, including at an angle, or the like, since the level of fluid cannot be maintained, then cooling of the motor and parts contained within the motor cavity is affected and may be ineffective. Since it is beneficial for the motor, its parts, and other components and devices contained in the motor cavity to be mostly if not fully submerged in the oil/fluid for cooling, then, if this cavity is only partially filled, the parts and components will be not only exposed to air but also have reduced cooling and a risk of over-heating. This issue can occur during initial start-up, where the liquid has drained down to that level while the vehicle is parked. This issue can also occur during vehicle driving in hybrid vehicles if the pump is used only when the electric motor is operating, as the liquid may drain down while the internal combustion engine is operating for longer periods of time. But it can also occur in some designs even if the pump is always running during vehicle operation, as the fill level may take time to rise, particularly if there is not a sufficiently large difference between the drain rate through the return port and the intake rate through the shaft (or other path for delivering the liquid to the motor cavity) and/or the pump is being run at a lower speed.

As a result, the disclosed pump systemincludes an extra component to control the level of liquid/fluid in the motor cavity, independently of the installed orientation of the pumpand system housing.

According to embodiments, a fill level control plateis positioned between the intermediate housing walland the motor cavityin the pump system. A detailed, cross-sectional view of the fill level control plateis shown in, whileshows a top view of the plate, as mounted. In an embodiment, the fill level control plateis positioned against at least a portion of the intermediate housing wall. The fill level control platemay be placed inside an area formed by the extension wall, for example, in one embodiment. In one embodiment, as seen in, the control plateis substantially circular and is sized for fitting into the area defined inside of the extension wallof the intermediate housing wall. The fill level control plateforms an overflow region(see) between the intermediate housing wall(e.g., its recessed region(s)) and the control platewithin the pump system. In an embodiment, the fill level control plateincludes an overflow opening(see) therethrough for directing (or selectively directing) fluid flow of liquid from the motor cavityto the overflow region. Such an overflow openingmay be a portion or region that is cut out of an edge of the plate, such as shown infor example. However, such depiction and shape is not intended to be limiting. For example, the opening could be formed through the plate and spaced from its outer edge, rather than being cut into its outer edge.

In embodiments, such as shown in, an edge of the fill level control platemay have one or more stress relieving openings therearound, which are sized for such purposes while still restricting fluid flow.

According to embodiments, the fill level control plateis installed with the overflow openingat a location spaced radially from the drive shaftand substantially vertically above the drive shaftand the pump inlet return port. In embodiments, the overflow openingmay be positioned in an orientation that places it in the highest position depending on the (intended) installation orientation. As such, the fill level control plateis configured to cause a liquid levelwithin the motor cavityto rise during operation of the pump system, such as shown and described with reference to. In particular, when the systemis mounted substantially horizontally or horizontally or an at acute angle relative to a horizontal, during operation, the auxiliary circuithas a return paththrough the electric motor(and motor cavity) for directing a portion of fluid flow for cooling the motor, through the overflow openingin the fill level control plateand relatively down a pathin the overflow region, to return back to the pumpvia the pump inlet return port.

In an embodiment, fill level control platehas a first axial side (pump-facing side) and a second axial side (motor-facing side). In the illustrated embodiment of, the first axial side of the fill level control platefaces the intermediate housing walland the second axial side of the fill level control platefaces the motor statorof the electric motor. Since the intermediate housing wallmay include recessed regiontherein, then, the recessed regionfacing the fill level control platemay assist in forming the overflow regiontherebetween. The overflow regionthus has an axial depth defined between the second axial side of the intermediate housing wall(e.g. its recessed region) and the first axial side of the fill level control plate. Accordingly, the overflow regionallows for flow of liquid relatively above the pump, between intermediate housing walland the plate. Since such liquid in the overflow regionis directed to the pump inlet return port, then, if the portis provided relatively below the drive shaftand adjacent the pump inlet, then each side [of the pump inlet side] of the pumpeffectively draws in (via suction or negative pressure) liquid. That is, in embodiments, the pump inlet return port, which is an opening or hole, acts as an inlet shadow port connected to the pump. More specifically, the pump inlet return portmay be positioned so as to direct a portion of the fluid to the back to the inlet section of the pump, in embodiments herein. According to embodiments, the connection to the inlet section of the pump via the pump inlet return portmay be located at a lowest point once the pump systemis installed or mounted. For example, the pump inlet return portmay be positioned relatively near the bottom of the system, as shown in. In such a configuration, then, the fill level control plateassists in avoiding failure or negative performance of the system(e.g., due to overheating and a low level of liquid in the motor cavity) by using and positioning its overflow openingto allow for shifting of the return of liquid from the motor cavity. As such, fluid flow is directed to where it is needed by the fill level control platelimiting and/or sealing off points within the pump system. The disclosed pump system and more particularly the use of the fill level control plateprovides freedom to control a liquid level relative to the orientation of the pump system.

The inlet portthus can be at any location, as the fill level control plate's overflow openingsets the fill level in the motor cavity. Thus, if the customer decides to install the pump in a different rotational orientation (which may be dictated by packaging space, access to connectors, etc.), the only change required to manage the fill level is to change to rotational orientation of the control plate so that its overflow openingis at a suitably high location to set a corresponding fill level. Likewise, this enables the same pump to be used for different applications, e.g., vehicles, where the installation orientation will vary.

As shown inand, according to an embodiment, the fill level control platemay have a number of spring tabspositioned circumferentially therearound. The spring tabsare configured for engagement with the motor stator, as shown in, to hold the control platein place. In an embodiment, the statorof the motor is configured to hold the control plate against the surface of the intermediate housing wall. As such, providing the spring tabsassists in maintain engagement therewith, setting a position and placement of the control platesuch that there is no axial movement of the control platerelative to the intermediate housing wall. In the illustrated embodiment, six spring tabsare shown; however, such number is an example only and not intended to be limiting.

As previously described, according to an embodiment, the intermediate housing wallhas an alignment portion, which may be centrally located and receive the drive shaftthrough its inner opening. The alignment portionextends axially and its outer surface may be utilized as a mounting projection for aligning and mounting the fill level control platethereon. For example, the fill level control platemay include a central openingtherein through which the alignment portionof the intermediate housing wallextends.

In one embodiment, the alignment portionmay be a polygonal alignment portion. More specifically, in such an embodiment, an outer surfaceof the alignment portionmay include a number of linear edges or flats along its perimeter (see) which form a polygonal shape therearound. The polygonal shape may be any number of shapes, including, but not limited to, a hexagon, an octagon, and a dodecagon shape. Such a polygonal shape may be provided such that the fill level control plateis configured to be installed in a plurality or number of discrete rotational positions. Accordingly, such a configuration enables movement and orientation of the overflow openingrelative to (around) the drive shaft. Further, this design allows the same part to be used with different installation orientations for different customers. In an embodiment, then, the central openingof the fill level control platemay be a corresponding polygonal opening for mating with the outer surfaceof the polygonal alignment portionon the intermediate housing wallat one of the number of discrete rotational positions. Since this polygonal shape on the control plateis complementary to the shape of the alignment portion, then, the number of linear edges (or flats) around the central openingcorresponds to the number of linear edges around the alignment portion. Again, the overflow openingof the fill level control platemay thus be moved to a different location (than that as depicted in) while still being spaced radially from the drive shaftand substantially vertically above the drive shaftand the pump inlet return port(not shown in, as the control plateis covering this port).

In an embodiment, the alignment portionhas twelve flats around its perimeter. Accordingly, the fill level control platemay be positioned in twelve different positions around the axis A-A, i.e., the overflow openingmay be moved to twelve different positions within the motor cavity. This exemplary number of flats, however, is not intended to be limiting. In embodiments, four, six, eight, or ten flats may be provided.

In other embodiments, the rotational alignment can be provided using other techniques. For example, the inner periphery of wallcould have flat surfaces and the outer edge of the platecould have corresponding flat surfaces. The installation and orientation is similar to the illustrated design, except that the flat surface engagement occurs at the outer edge of plateand wall. Likewise, teeth or other inter-engaging structure (at the inner edge of the plateand the alignment portion, or also at the outer edge of the plateand the inner surface of wall) could be inter-engaged to maintain the rotational orientation of the plate. The plate likewise have a fastener hole therethrough, and the wallcould have a number of circumferentially spaced fastener receiving openings, such that a fastener can be inserted to secure the platein a desired rotational orientation. Any suitable approach for securing the platein its desired rotational orientation may be used.

Turning to, then, the updated auxiliary circuitis illustrated, in addition to the main fluid path. The disclosed pump systemis shown with the fill level control platemounted therein, adjacent (or against) the intermediate housing walland forming the overflow region. As shown via the drawn fluid path, during operation of the pump system, negative pressure (suction) causes a portion of the liquid to be drawn through the boreof the hollow drive shaftand then direct the fluid flow of liquid into the motor cavity. The liquid follows return paththrough the electric motor, for cooling the rotor/stator of the motor. The use of the fill level control plateallows not only for adjustment of the auxiliary fluid flow path but also filling of the motor cavitywith liquid to a liquid levelby restricting flow of the liquid out of the motor cavity. The auxiliary circuitallows for a portion of liquid flow through overflow opening(which is positioned near the top in) to the overflow region, thus allowing the motor cavityto fill substantially, if not almost entirely full. The portion of liquid that flows through overflow openingthen follows a return pathof the auxiliary circuit such that it is directed relatively down the overflow region, to the pump inlet return port(positioned near the bottom in), to return back to the pump. Accordingly, the disclosed design enables cooling of the motor parts and components in the motor cavityvia the addition of the fill level control plate.

In an embodiment, the system housingfurther include an electronic control unit (ECU) or controllertherein. The controlleris configured, among other features, to drive the electric motorto drive the drive shaftof the pump. In the illustrated embodiments, the ECU is shown in the form of a printed circuit board (PCB)with electrical components thereon. As known in the art, a number of components, such as sensors, temperature sensors/heat sink, etc. may mounted on the controlleror PCB. In an embodiment, the electric motoris flanked by the controllerand the pumpin the pump assembly/system. That is, the pumpand the controllermay be on opposing sides of the electric motor.

In embodiments, which is also depicted in the Figures, the controllermay be provided within the motor cavity. That is, the controllermay be a “wet” controller associated with a wet motor and cooled via liquid in the motor cavity. Similar to the previous description, orientation determines how much the motor/controller cavitymay be filled with liquid. completely fill with oil. Like the electric motor, it is critical for the controllerto be mostly if not fully submerged in the liquid for cooling purposes because exposure of the controller to air will have reduced cooling and a risk of over-heating. As such, using the fill level control platefurther provides an advantage of cooling a wet controller when provided in the motor cavity. In operation of pump systemwith wet controller, the pumpis configured to pressurize input fluid (as known) and output the pressurized fluid through the outlet. In addition, a portion of liquid is directed through the drive shaftto an opposite end thereof and discharged into the motor cavitywhich contains the electric motorand the controller(i.e., PCB). The fill level control plateis held up against the intermediate housing wallvia contact with the motor stator, restricting liquid flow to the pump inlet return connection (port) everywhere but through overflow openingin the plate. This overflow openingmay be positioned in the orientation that places it in the highest position depending on the installation orientation. Thus, the portion of liquid in the auxiliary circuitflows through the electric motorvia pathand back to the pumpvia the overflow openingand overflow regionof the fill level control plateand intermediate housing wall, through path, and then the pump inlet return port.

Of course, it should be understood that, in accordance with embodiments herein, particularly when the controlleris provided in the motor cavity, the auxiliary circuitmay include directing liquid towards sensors and devices associated with or mounted on the controller. Such sensors and devices may be directly exposed to the path, according to an embodiment. However, such sensors and devices may not necessarily be exposed directly to the liquid being pumped. Similarly, the controllerdoes not need to be a wet controller that is included in the motor cavityand subject to liquid. Rather, the covermay include a closed housing portion therein for housing the controller and electronics, without being exposed to the liquid.

It should be understood that the auxiliary circuitmay also assist in drawing heat, i.e., cooling, additional parts within the pump systemor assembly. Such parts may include, but are not limited to, cooling the controller/ECU (by way of the flow of fluid/lubricant through the pathand drawing heat therefrom and its components) and/or cooling the housing components used to secure the motor parts therein.

The portion or percentage of the liquid provided to the auxiliary circuit or pathis not intended to be limited with regards to amount or volume. In an exemplary embodiment, the percentage of fluid provided to the auxiliary circuitmay be in the range of approximately 1% to approximately 50%. In another exemplary embodiment, the percentage of fluid provided to the auxiliary circuit may be in the range of approximately 1% to approximately 25%. In yet another exemplary embodiment, the percentage of fluid provided to the auxiliary circuit may be in the range of approximately 1% to approximately 10%. In still yet another exemplary embodiment, the percentage of fluid provided to the auxiliary circuit may be in the range of approximately 1% to approximately 5%. In one embodiment, the percentage of fluid provided to the auxiliary circuit is approximately 5%.

The pump housing, motor casing, intermediate housing wall, fill level control plate, and covermay be formed from any number of heat conductive materials, such as aluminum or other metals, in accordance with embodiments herein. Alternatively, in other embodiments, such components may be formed from other materials, including plastic. The materials used to form the parts of the pump systemmay be materials that are capable of allowing fluid (e.g., oil) flow with heat emitting surfaces, according to embodiments herein.

It is noted that a number of features have been depicted in the drawings in a particular location. However, it should be noted that elements may be moved without deviating from the herein disclosed features and advantages. Moreover, the depictions and placement of the pump systemas shown in the Figures is not meant to limit the positioning or mounting of the pump system itself. That is, while the pump systemis shown in a horizontal position such that the motorand optional controlleris positioned relatively to the right in the motor cavityin the Figures, which are both to the right of the pump, the pump systemand thus its housed components may be positioned at any number of angles that are different than those shown in the Figures, or mirrored, and accomplish the same effects. As one example, the pump systemmay be turned 15 to 45 degrees in a relatively upward direction and mounted at an angle, such that the pump inletis on a lower, left side and the motor cavityon an upper right side.

In addition to providing the disclosed pump system, this disclosure also

encompasses a method of manufacturing such a pump system. Such method includes, but is not limited to: providing a housing, such as system housing(and optionally any of its associated housing pieces (e.g., pump housing, motor housing, etc.) having an intermediate housing wall; providing a pumpand an electric motor, the pump having a pump inlethaving a pump inlet portB and a pump outlethaving a pump outlet portB; and providing a drive shaftto be rotatably driven by the electric motor, for driving the pumpto pressurize fluid received through a fluid pathof the pumpfrom the pump inletfor output from an outlet pathA to the pump outlet. The method also includes positioning the pumpand the electric motorwithin the housing; positioning the intermediate housing walltherebetween and covering a motor cavitywithin the housingfor the electric motor; and installing a fill level control platebetween the intermediate housing walland the motor cavity, forming an overflow regionbetween the intermediate housing walland the control plate. In the method, the pump systemfurther includes an auxiliary circuitconfigured to direct a portion of fluid flow to the motor cavity; the intermediate housing wallhas a pump inlet return portfor directing the fluid flow from the motor cavityto the pump; and the fill level control platehas an overflow openingtherethrough for directing fluid flow from the motor cavityto the overflow region. The installation of the fill level control plateincludes positioning said overflow openingat a location spaced radially from the drive shaftand substantially vertically above the drive shaftand the pump inlet return port, such that the fill level control platecauses a liquid level within the motor cavityto rise during operation of the pump systemand the auxiliary circuithas a return path,through the electric motorfor directing the portion of fluid flow for cooling the motorthrough the overflow openingin the fill level control plateand relatively down the overflow region, to return back to the pumpvia the pump inlet return port.

As noted previously, in this disclosure, the auxiliary circuitor auxiliary fluid path may deviate from the main pathof the pump; that is, deviating is a term used to describe that there is liquid/fluid communication between some portion of the liquid/fluid flow in the pump's pathand the auxiliary circuit. In the illustrated embodiment, the deviation may be regarded as pump inlet side receiving both liquid via the pump inlet pathA as well as the liquid returned from return portvia the auxiliary circuitincluding the hollow drive shaft, as both liquid flows end up in the pump's fluid path. The illustrated embodiment may also be regarded as having a deviation in the sense that the liquid/fluid flowing into the pump's inlet mouth at the left end in, via pump inlet, is partially drawn into the hollow shaft, while also being drawn into the pump inletA. Similarly, if part of the output from the outlet side of the pumpis delivered to the motor cavity, that may also be regarded as deviation from the pump's fluid path that flows out the pump outlet portB and pump outlet. Thus, when the term deviation is used in reference to the auxiliary path's relation to the pump's main fluid path, a broad interpretation is intended to refer to any such fluid communication between the two.