Electric two-fluid pump with single motor

Abstract

A fluid pump includes a housing, a motor disposed within a motor portion of the housing, a delivery pump element disposed within a delivery portion of the housing, and a return pump element disposed within a return portion of the housing. A drive shaft is coupled with each of the delivery pump element and the reflux pump element, and operation of the motor operates the delivery pump element and the reflux pump element contemporaneously through the drive shaft. The delivery pump element is configured to deliver fluid from a reservoir to a drive unit, and the reflux pump element is configured to deliver the fluid from a sump assembly of the drive unit to the reservoir.

Description

Technical Field

[0001] The present invention relates generally to fluid pumps and, more particularly, to dual motor fluid pumps that can be used to scavenge fluid from one or more reservoirs to a reservoir and also deliver fluid from the reservoir to a mechanical assembly. Background Art

[0002] In mechanical assemblies, fluids are often used to provide lubrication and cooling functions within the assembly. Fluid pumps can be used to deliver this fluid from a reservoir to a separate location to provide the desired function. Summary of the invention

[0003] According to one aspect of the present disclosure, a fluid pump includes a housing having a motor portion, a delivery portion, and a return portion. The motor is disposed in the motor portion. The motor is operably coupled to a drive shaft, which extends from the motor and passes through the delivery portion and the return portion. A delivery pump element is disposed in the delivery portion and coupled to the drive shaft. A return pump element is disposed in the return portion of the housing and coupled to the drive shaft, wherein the operation of the motor operates the delivery pump element and the return pump element through the drive shaft. The delivery pump element is configured to deliver fluid from a reservoir to a drive unit, and the return pump element is configured to deliver the fluid from a sump assembly of the drive unit to the reservoir.

[0004] According to another aspect of the present disclosure, a fluid pump includes a housing, a motor disposed in a motor portion of the housing, a delivery pump element disposed in a delivery portion of the housing, and a return pump element disposed in a return portion of the housing. A drive shaft is coupled to each of the delivery pump element and the return pump element, and operation of the motor synchronously operates the delivery pump element and the return pump element through the drive shaft. The delivery pump element is configured to deliver fluid from a reservoir to a drive unit, and the return pump element is configured to deliver the fluid from a sump assembly of the drive unit to the reservoir.

[0005] According to another aspect of the present disclosure, a fluid pump includes a housing, a motor disposed in a motor portion of the housing, a delivery pump element disposed in a delivery portion of the housing, a return pump element disposed in a return portion of the housing, and a drive shaft having a spline. The drive shaft extends from the rotor of the motor to each of the delivery pump element and the return pump element. The operation of the motor operates the delivery pump element and the return pump element simultaneously through the drive shaft. The delivery pump element is configured to deliver fluid from a reservoir to a drive unit. The return pump element is configured to deliver the fluid from a sump assembly of the drive unit to the reservoir. During the operation of the motor, the spline delivers a portion of the fluid into the motor portion and at least around the rotor of the motor to absorb heat from the motor and a printed circuit board positioned to communicate with the motor portion.

[0006] Those skilled in the art will further understand and appreciate these and other features, advantages and objects of the present invention by referring to the following specification, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In the attached picture:

[0008] Figure 1 is an end perspective view of one aspect of a fluid pump;

[0009] Figure 2 yes Figure 1 Another end perspective view of the fluid pump;

[0010] Figure 3 yes Figure 1 A side elevation view of a fluid pump;

[0011] Figure 4 yes Figure 1 Another side elevation view of the fluid pump;

[0012] Figure 5 yes Figure 1 An end elevation view of a fluid pump;

[0013] Figure 6 yes Figure 1 Another end elevation view of the fluid pump;

[0014] Figure 7 yes Figure 1 An exploded perspective view of a fluid pump;

[0015] Figure 8 yes Figure 1 Another exploded perspective view of the fluid pump;

[0016] Fig. 9 yes Figure 1 A cross-sectional view of the fluid pump along line IX-IX;

[0017] Fig.10 yes Figure 1 A cross-sectional view of the fluid pump along line XX;

[0018] Fig.11 is a perspective view of a port housing containing a gear pump;

[0019] Fig.12 is a perspective view of a pump cover engaged with a gear pump housing;

[0020] Fig.13 is a perspective view of a pump body receiving one aspect of a transfer pump;

[0021] Fig.14 yes Fig.13 A relative perspective view of a pump body and showing one of the bearing brackets for supporting a drive shaft of a motor of the fluid pump;

[0022] Fig.15 It shows the use of Figure 1 A schematic diagram of one aspect of a fluid pump showing the flow of a fluid through a fluid path;

[0023] Fig.16 is a schematic perspective view of a fluid pump, showing the flow of fluid through Figure 1 The movement of the delivery pump element and the return pump element of the fluid pump;

[0024] Fig.17 is another schematic perspective view of a fluid pump, showing the flow of fluid through Figure 1 The movement of the delivery pump element and the return pump element of the fluid pump;

[0025] Fig.18 is an exploded perspective view of a motor portion of a fluid pump;

[0026] Fig.19 yes Fig.10 A cross-sectional view of a fluid pump and illustrating a heat transfer path within the fluid pump;

[0027] Fig. 20 yes Fig.10 A cross-sectional view of a fluid pump and illustrating the configuration of a bearing support extending along a drive shaft and defining an axial fluid conduit along the drive shaft;

[0028] Fig.21 yes Fig.10 A cross-sectional view of a fluid pump of FIG. 1 and illustrating the configuration of an axial fluid conduit extending along the drive shaft for lubricating the drive shaft, the delivery pump element, and the return pump element;

[0029] Fig. 22is a perspective view of one aspect of a pump body of a fluid pump having a pressure side port for delivering fluid along a spline assembly;

[0030] Fig.23 is included in Figure 1 A perspective view of one aspect of the rotor and drive shaft within a fluid pump

[0031] Fig.24 yes Fig.23 An exploded perspective view of a rotor and a drive shaft;

[0032] Fig.25 is a perspective view of the rotor and drive shaft and illustrates the interconnection with the delivery pump element and the return pump element of the fluid pump; and

[0033] Fig.26 yes Fig.25 A cross-sectional view of a delivery pump element along line XXVI-XXVI and showing the splines of the drive shaft, which define a portion of an axial fluid conduit that allows fluid to move along the drive shaft for lubricating components of the fluid pump. DETAILED DESCRIPTION

[0034] Reference will now be made in detail to currently preferred embodiments of the present disclosure, examples of which are shown in the accompanying drawings. When appropriate, the same reference numerals will be used throughout the drawings to refer to the same or similar parts. In the drawings, the structural elements depicted are not to scale, and certain components are enlarged relative to other components for emphasis and ease of understanding.

[0035] As required, detailed embodiments of the present disclosure are disclosed herein; however, it should be understood that the disclosed embodiments are merely exemplary embodiments of the present invention and may be implemented in various and alternative forms. These figures are not necessarily detailed designs; some schematic diagrams may be enlarged or minimized to show a functional overview. Therefore, the specific structural and functional details disclosed herein should not be interpreted as limiting, but only as a representative basis for teaching those skilled in the art to adopt the present invention in various ways.

[0036] For the purpose of this description, the terms "upper", "lower", "right", "left", "rear", "front", "vertical", "horizontal" and their derivatives shall be used in the same manner as described above. Figure 1-26 The present invention relates to the concepts oriented in the drawings. However, it should be understood that the present concepts can adopt various alternative orientations, except where expressly specified to the contrary. It should also be understood that the specific devices and processes shown in the drawings and described in the following specification are merely exemplary embodiments of the inventive concepts defined in the appended claims. Therefore, unless the claims expressly state otherwise, specific dimensions and other physical characteristics related to the embodiments disclosed herein should not be considered limiting.

[0037] The present illustrated embodiments reside primarily in a combination of method steps and apparatus components related to a fluid pump, the fluid pump including a single motor for driving a delivery pump element that delivers fluid from a reservoir to a drive unit having at least one storage tank, and wherein the single motor also drives a return pump element for delivering fluid from at least one storage tank to the reservoir. Accordingly, where appropriate, apparatus components and method steps are represented in the accompanying drawings by conventional symbols, showing only those specific details that are relevant to understanding the embodiments of the present disclosure so as not to obscure the present disclosure with details that would be apparent to one of ordinary skill in the art having the benefit of the description herein. Further, like numbers in the description and drawings represent like elements.

[0038] As used herein, when the term "and / or" is used in a list of two or more items, it means that any one of the listed items can be taken alone, or any combination of two or more of the listed items can be taken. For example, if a composition is described as comprising components A, B, and / or C, the composition can comprise A alone; B alone; C alone; a combination of A and B; a combination of A and C; a combination of B and C; or a combination of A, B, and C.

[0039] In this document, relational terms such as first and second, top and bottom, etc. may be used only to distinguish one entity or action from another entity or action, and do not necessarily require or imply any actual such relationship or order between such entities or actions. The terms "comprises" or "comprising" or any other variations thereof are intended to cover non-exclusive inclusions, such that a process, method, article, or apparatus that includes a series of elements does not include only those elements, but may include other elements that are not explicitly listed or inherent to such process, method, article, or apparatus. In the absence of further constraints, a phrase preceded by "an element comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0040] As used herein, the term "about" means that the amount, size, formulation, parameter and other quantities and characteristics are not and need not be exact, but may be approximate and / or larger or smaller as needed, thereby reflecting tolerances, conversion factors, rounding, measurement errors, etc. and other factors known to those skilled in the art. When the term "about" is used to describe a value or a range endpoint, the disclosure is understood to include the specific value or endpoint mentioned. Regardless of whether the numerical value or range endpoint in the specification is listed as "about", the numerical value or endpoint of the range is intended to include two embodiments: one modified by "about" and one not modified by "about". It should be further understood that the endpoint of each range is significant relative to the other endpoint and independently of the other endpoint.

[0041] As used herein, the terms "substantial" and "substantially" and variations thereof are intended to indicate that the described feature is equal to or approximately equal to a value or description. For example, a "substantially flat" surface is intended to mean a flat or approximately flat surface. In addition, "substantially" is intended to mean that two values ​​are equal or approximately equal. In some embodiments, "substantially" can mean values ​​that are within about 10% of each other, such as within about 5% of each other, or within about 2% of each other.

[0042] As used herein, the terms "the," "a," or "an" mean "at least one," and should not be limited to "only one," unless clearly indicated to the contrary. Thus, for example, reference to "a component" includes embodiments having two or more such components unless the context clearly indicates otherwise.

[0043] like Figure 1-26 , reference numeral 10 generally refers to a fluid pump contained within a mechanical assembly, such as a drive unit 12, for delivering a fluid 14 from a sump assembly 15 to a reservoir 18, and then from the reservoir 18 to the drive unit 12 including the sump assembly 15, which may include a sump 16 or multiple sumps 16. The fluid pump 10 includes a plurality of pump elements for the drive unit 12, which move the fluid 14 between various components within a fluid circuit, such as a hydraulic system 20. According to various aspects of the device, the fluid pump 10 includes a housing 22, which is composed of a plurality of components attached together to form the fluid pump 10. The delivery portion 24 of the fluid pump 10 includes a delivery pump element 26 disposed within the housing 22. The return portion 28 of the fluid pump 10 includes a return pump element 30 also disposed within the housing 22. A motor 32 is disposed within the housing 22, which typically drives the delivery pump element 26 and the return pump element 30 simultaneously through a drive shaft 34. The delivery portion 24 is configured to deliver the fluid 14 from the reservoir 18 to the drive unit 12. The return pump element 30 is configured to deliver the fluid 14 from at least one of the reservoirs 16 of the drive unit 12 to the reservoir 18 where the fluid 14 can then be delivered back to the drive unit 12 using the delivery pump element 26.

[0044] refer to Figure 1-26The drive unit 12 that is cooled or lubricated using the fluid pump 10 may be in the form of a transmission, or other similar mechanical assembly within a specific application, typically a vehicle application. Using a fluid pump 10 having a delivery portion 24 and a return portion 28 allows the system to maintain a desired level of fluid 14 at the drive unit 12. Fluid 14 that may not be needed within the drive unit 12 at this time can be temporarily maintained or stored within the reservoir 18 for subsequent recirculation throughout the hydraulic system 20. By maintaining a desired level of fluid 14 within the drive unit 12, fluid resistance within the drive unit 12 is minimized, and the drive unit 12 can have a smaller overall size or have a lower profile to accommodate the need for a smaller amount of fluid 14 within the sump 16 of the drive unit 12.

[0045] The fluid pump 10 utilizes a single motor 32 to control each of the delivery pump element 26 and the return pump element 30. The delivery pump element 26 and the return pump element 30 are integrated together to provide compact packaging and weight reduction within the fluid pump 10. As discussed herein, the motor 32 is configured to operate each of the delivery pump element 26 and the return pump element 30 simultaneously or concurrently via the drive shaft 34.

[0046] Reference again Figure 7-26 , the motor 32 driving the delivery pump element 26 and the return pump element 30 can be an electric motor 32 having a rotor 40 in electromagnetic communication with a stator 38. The excitation winding 42 of the stator 38 causes the rotor 40 to rotate about a rotation axis 44. The rotor 40 is attached to a drive shaft 34, which extends through the housing 22 of the fluid pump 10. The drive shaft 34 extends through the delivery portion 24 and the return portion 28 of the housing 22. In this way, the drive shaft 34 engages each of the delivery pump element 26 and the return pump element 30 for operating each of these pump elements within the fluid pump 10. In addition, when the motor 32 is operated, each of the delivery pump element 26 and the return pump element 30 is simultaneously operated to deliver the fluid 14 through the hydraulic system 20 and to deliver the fluid between the drive unit 12 and the reservoir 18, which thus includes the sump assembly 15. The rotor 40 generally includes a magnet 46, which is attached to the rotor core 48 and embedded in the rotor outer mold 49. The drive shaft 34 is fixed to the rotor core 48 via a rotor outer mold 49 .

[0047] Reference again Figure 7-21 , the fluid 14 within the drive unit 12 is collected in each of the tank assemblies 15 for the drive unit 12. Although the first tank 50 and the second tank 52 are Fig.15 and 161, but it is contemplated that a single reservoir 16 or multiple reservoirs 16 may be included in the reservoir assembly 15 for a particular drive unit 12. Where multiple reservoirs 16 are included in the reservoir assembly 15, the fluid pump 10 may include a separate and dedicated reflux inlet 54 for each respective reservoir 16 of the drive unit 12. When the motor 32 for the fluid pump 10 is activated, the reflux pump element 30 is rotated by operation of the drive shaft 34.

[0048] like Figure 1-12 As illustrated in FIGS. 15-17, the fluid pump 10 includes a first return inlet 55 and a second return inlet 57, which may be referred to as return inlets. These first return inlet 55 and the second return inlet 57 cooperate with the return pump element 30 to draw fluid 14 from at least one of the first reservoir 50 and the second reservoir 52, and typically both, and into a contoured pump chamber 206 of the port housing 108 of the fluid pump 10. The pump chamber 206 houses a gear pump 200 having a drive gear 202 meshed with at least one idle gear 204 and typically two opposing idle gears 204. The meshing engagement between the drive gear 202 and the opposing idle gears 204 facilitates drawing the fluid 14 from the first reservoir 50 and the second reservoir 52, and through the first return inlet 55 and the second return inlet 57. During operation of the drive gear 202, the drive gear 202 meshes with the opposing idler gear 204 such that all three gears operate simultaneously to move the fluid 14 through the contoured pump chamber 206 of the port housing 108. The return pump element 30 then moves the fluid 14 toward the reservoir 18 by extending from the contoured fluid cavity and through the opposing outlet port 92 of the pump cover 104. The fluid 14 is then collected within the reservoir 18 for further recirculation by the fluid pump 10, typically the delivery pump element 26, as will be more fully described below.

[0049] Reference again Figure 1-12 15-17, the return inlet 54 extends from the corresponding sump 16 of the drive unit 12 and extends through the inlet port 90 of the return pump element 30 into the contoured pump chamber 206 that houses the gear pump 200. A corresponding outlet port 92 extends from the pump cover 104 for delivery to the reservoir 18. The outlet ports 92 can be configured to merge together and be incorporated within the return portion 28 of the fluid pump 10. Opposing outlet ports 92 can also be incorporated within an area defined between the pump cover 104 and the manifold 176 that receives the fluid pump 10. Typically, a single fluid conduit extends from the fluid pump 10 for delivery to the reservoir 18.

[0050] The reflux passage 102 that makes up the reflux inlet 54, the inlet port 90, the outlet port 92, and the reflux outlet 100 can be defined within the reflux portion 28 of the fluid pump 10. Typically, these passages are defined within the pump cover 104 and the port housing 108. Using this configuration, the reflux pump element 30 is able to draw fluid 14 from any one or both of the first sump 50 and the second sump 52 for the drive unit 12, so that the fluid 14 from these sump 16 can be delivered to the reservoir 18 for further use. Therefore, the collection of fluid 14 in any one sump 16 or multiple sumps 16 of the sump assembly 15 will cause the fluid 14 to be drawn into the reflux pump element 30. In this way, whether the fluid 14 in the sump assembly 15 is contained in a single sump 16 or is dispersed in all sumps 16, the reflux pump element 30 can be operated to deliver the fluid 14 from the sump assembly 15 through the reflux pump element 30 and to the reservoir 18.

[0051] Reference again Figure 1-12 15-17, a fluid path between a pair of reflux inlets 54 to a single reflux outlet 100 can be defined between the pump cover 104 and a manifold 176 receiving the fluid pump 10. The reflux inlet 54 can include a gasket or multiple gaskets, such as a spring seal 114 spanning a reflux flow space 116 defined between an end surface of the pump cover 104 and the manifold 176. The reflux outlet 100 can be in communication with the reflux flow space 116. In exemplary operation, the fluid 14 from the first reservoir 50 and the second tank 52 moves through the spring seal 114 separated from the flow space 116 and then enters the contoured fluid chamber 138 of the reflux pump element 30 through the inlet port 90, as described herein. The fluid 14 then flows out of the contoured fluid cavity through the opposite outlet port 92 and into the reflux flow space 116 defined between the reflux surface 112 of the pump cover 104 and the manifold 176. This repulsive force 76 from the gear pump 200 within the pump chamber 206 pushes the fluid 14 through the opposing outlet ports 92 and through the single reflux outlet 100 and toward the reservoir 18. With this configuration, the two reflux inlets 54 and the reflux pump element 30 provide a continuous flow of the fluid 14 toward the single reflux outlet 100 and the reservoir 18.

[0052] As described herein, in some cases, one of the reservoirs 16 may be dry while the other reservoir 16 may include a quantity of fluid 14. In such cases, the return pump element 30 is able to provide sufficient fluid 14 through the return portion 28 of the fluid pump 10 for delivery of the fluid 14 to the reservoir 18. As described herein, the fluid 14 may flow through one of the drive gear 202 and the idler gear 204 of the return pump element 30, with little to no fluid 14 moving through the interface between the drive gear 202 and the opposing idler gear 204. With this configuration, a continuous supply of fluid 14 may be delivered from one or both of the reservoirs 16 within the reservoir assembly 15 and delivered to the reservoir 18 for subsequent recirculation through the hydraulic system 20 via the delivery pump element 26, as described herein.

[0053] Reference again Figure 1-26 , the delivery portion 24 of the fluid pump 10 includes a delivery pump element 26 that draws the fluid 14 from the reservoir 18 and moves the fluid 14 through the delivery pump element 26 and toward the drive unit 12 having the sump assembly 15. Typically, the delivery portion 24 of the fluid pump 10 will include a single delivery inlet 120 that receives the fluid 14 from the reservoir 18 and a single delivery outlet 122 that delivers the fluid 14 toward the drive unit 12.

[0054] like Figure 1-26 , the reflux portion 28 of the fluid pump 10 may include two dedicated reflux inlets 54 for receiving fluid 14 from each corresponding reservoir 16, respectively. This different number of delivery inlets 120 in the delivery portion 24 and the reflux inlets 54 in the reflux portion 28 is addressed by the increased capacity of the reflux pump element 30 for drawing fluid 14 from at least one of the first reservoir 50 and the second reservoir 52 of the reservoir assembly 15. The reflux portion 28 includes an increased capacity of the reflux pump element 30. In this way, the amount of fluid 14 delivered by the reflux pump element 30 is generally less than the maximum flow capacity of the reflux pump element 30, while also delivering enough fluid 14 to meet the flow requirements of the delivery pump element 26. Therefore, under typical operating conditions, the reflux pump element 30 returns an amount of fluid 14 that is similar or substantially similar to the capacity of the delivery pump element 26 of the fluid pump 10. Thus, this increased capacity of the reflux pump element 30 can accommodate all of the fluid 14 in the reservoir assembly 15 in the single reservoir 16 so that the fluid 14 can move from the single reservoir 16 through the reflux pump element 30 and into the reservoir 18 for delivery to the drive unit 12 by the delivery pump element 26. Thus, the reflux pump element 30 ensures that a sufficient amount of fluid 14 is contained within the reservoir 18 for manipulation by operation of the delivery pump element 26.

[0055] As an example and not limitation, where the delivery pump element 26 includes a capacity of four cubic centimeters per revolution, it is contemplated that the reflux pump element 30 may include a capacity of eight cubic centimeters per revolution. Likewise, under typical operating conditions, the reflux pump element 30 will return to the reservoir 18 an amount of fluid 14 that is the same or similar to the amount of fluid 14 delivered to the drive unit 12 by the delivery pump element 26. As discussed herein, the increased capacity of the reflux fluid pump 10 takes into account situations where one of the first sump 50 or the second sump 52 is dry and the other of the first sump 50 and the second sump 52 may include a greater amount of fluid 14. In such situations, all of the fluid 14 that is returning to the reservoir 18 over a period of time will move through only one of the reflux inlets 54, and only half of the operable pump chambers 70 of the reflux fluid pump 10 will generate the suction force 72 and the repulsion force 76 of the fluid 14 until the fluid 14 is allowed to collect in the other sump 16 of the first sump 50 and the second sump 52. Likewise, this configuration ensures that a continuous flow of fluid 14 is moved from one or both of the first and second reservoirs 50, 52 to the reservoir 18 and from the reservoir 18 to the drive unit 12 for providing adequate cooling and lubrication functions as needed.

[0056] Reference again Figure 7-26 , the delivery pump element 26 may be in the form of a generating rotor 130, sometimes referred to as a cycloidal rotor, that is fixed within a pump body 132. The generating rotor 130 includes an internal gear 134 that rotates along the axis of rotation 44 of the fluid pump 10. An external eccentric gear 136 is placed within the pump body 132 in an offset configuration so that when the internal gear 134 rotates, a series of fluid cavities 138 are formed for conveying the fluid 14 through the delivery portion 24 of the fluid pump 10. As the generating rotor 130 rotates, the various fluid cavities 138 operate to draw the fluid 14 from the reservoir 18 using the generated suction force 72, and then push the fluid 14 toward the drive unit 12 using the generated repulsive force 76. As the fluid 14 is pushed toward the drive unit 12, the fluid 14 lubricates and cools the various components, and then falls toward the sump assembly 15 to be recirculated back to the fluid pump 10 using the reflux pump element 30 within the reflux portion 28 of the fluid pump 10.

[0057] Reference again Figure 1-26, the port housing 108 defines a portion of each of the delivery portion 24 of the fluid pump 10 and the return portion 28 of the fluid pump 10. Various gaskets, such as O-rings 154 and spring seals 114, are positioned at locations of the fluid pump 10 to maintain separation of the fluid 14 moving through the delivery portion 24 and the fluid 14 moving through the return portion 28 of the fluid pump 10. Typically, a single gasket is capable of separating the delivery inlet 120 from the delivery outlet 122 of the delivery portion 24 of the fluid pump 10. With this configuration, the delivery inlet 120 is positioned within the sidewall of the housing 22, typically between the pump body 132 of the fluid pump 10 and the port housing 108. The delivery outlet 122 of the fluid pump 10 is typically positioned within the pump cover 104. Thus, the return surface 112 of the pump cover 104 includes the return or return inlet 54 and the return or return outlet 100 of the return portion 28 of the fluid pump 10. This return surface 112 of the pump cover 104 also includes a delivery outlet 122 of the delivery portion 24 of the fluid pump 10. With this configuration, those portions of the fluid pump 10 that receive fluid 14 from the sump assembly 15 or deliver fluid 14 to the drive unit 12 having the sump assembly 15 are contained within the pump cover 104, and more specifically, within the return surface 112 of the pump cover 104. Those portions of the fluid pump 10 that receive fluid 14 from the reservoir 18 are contained within the sides of the fluid pump 10. With this configuration, the fluid pump 10 is better able to separate those portions of the fluid 14 associated with the delivery portion 24 from those amounts of fluid 14 moved by the return portion 28 of the fluid pump 10. Additionally, as described herein, the spring seal 114 positioned within the return inlet 54 and the delivery outlet 122 further separates the fluid 14 between the return portion 28 and the delivery portion 24 of the fluid pump 10.

[0058] Reference again Figure 1-26, the fluid pump 10 includes a motor portion or motor housing 160, which includes an outer mold that defines a motor cavity 168 around the stator 38 of the motor 32 and also allows the rotor 40 to rotate relative to the stator 38. The motor housing 160 may include a printed circuit board (PCB) 162 and various electrical connectors that can be used to deliver power to the motor 32 and also to transmit data to and from the components of the fluid pump 10 when in operation. It is contemplated that the motor 32 can be in the form of a variable speed motor 32, so that the controller 164 can be used to increase or decrease the speed of the motor 32 according to the fluid flow needs of the drive unit 12. In some cases, such as when the motor 32 is stopped, the transmission may not be in use, so that the fluid 14 does not need to circulate through the transmission. In such cases, the fluid pump 10 can be temporarily stopped. The PCB 162 within the motor housing 160 may include various sensors 166 that may monitor fluid temperature, fluid flow rate, various conditions of the fluid 14 moving through the fluid pump 10 , and other similar status information related to the fluid pump 10 and the fluid 14 moving therethrough.

[0059] As this article about Figure 1-26As discussed, the fluid pump 10 utilizes a motor 32 and a controller 164 included in or in communication with a PCB 162 to simultaneously drive each of the delivery pump element 26 and the return pump element 30. The delivery pump element 26 and the return pump element 30 are integrated together within the housing 22 of the fluid pump 10 to provide a compact package for delivering the fluid 14 to and from the reservoir 18 and the drive unit 12. As discussed herein, the reservoir assembly 15 of the drive unit 12 may include a first reservoir 50 and a second reservoir 52, so that a dual-fill or balanced gear pump 200 is used as the return pump element 30. This configuration utilizes two separate and dedicated return inlets 54 or dedicated return oil inlets to ensure that the fluid 14 is delivered from one or both of the first reservoir 50 and the second reservoir 52 and delivered to the reservoir 18. The return portion 28 of the fluid pump 10 combines the two return inlets 54 into a single hydraulic passage that delivers through the return outlet 100 and toward the reservoir 18. The lubrication and cooling functions of the fluid pump 10 are then provided by the delivery pump element 26, which draws fluid 14 from the reservoir 18 and moves the fluid 14 through various cooling and / or lubrication circuits. As discussed herein, it is generally unknown which of the multiple reservoirs 16 may have fluid 14 disposed therein at any particular time. The use of a return pump element 30 as a scavenge pump having multiple dedicated return or dedicated return inlets 54 can provide sufficient flow of fluid 14 from one or both of the first reservoir 50 and the second reservoir 52 into the reservoir 18. The use of a gear pump 200 as the return pump element 30 provides twice the pump displacement of the delivery pump element 26, thereby ensuring a continuous flow of fluid 14 through the hydraulic system 20.

[0060] Reference now Figure 1-26, the fluid pump 10 may include a housing 22 having a motor housing 160, a delivery portion 24, and a return portion 28. The motor 32 is disposed within the motor housing 160 and is operably coupled to a drive shaft 34 extending from the motor 32 and through the delivery portion 24 and the return portion 28. The drive shaft 34 includes a spline assembly 220 extending along a portion of the drive shaft 34 to engage with the drive gear 202 of the return pump element 30 and the internal gear 134 of the delivery pump element 26. Using this spline assembly 220 of the drive shaft 34, the fluid 14 delivered to the delivery pump element 26 and the return pump element 30 can move along the spline assembly 220 of the drive shaft 34. The fluid 14 moving along the spline assembly 220 can be used to lubricate the return pump element 30, the delivery pump element 26, and the rotor 40 of the motor 32 and the drive shaft 34. In this manner, the spline assembly 220 delivers the fluid 14 into the motor housing 160 and at least around the rotor 40 of the motor 32 to absorb heat 88 from the motor 32 and the PCB 162 positioned in communication with the motor housing 160. Through operation of the spline assembly 220, the fluid 14 and heat 88 are delivered away from the motor housing 160.

[0061] Reference again Figure 1-26 , the various components that make up the housing 22 for certain aspects of the fluid pump 10 may include, but are not limited to, a pump cover 104, a port housing 108, a pump body 132, and a motor housing 160. These components may be attached together by pump screws 170 that extend through these components, which are fixed to each other. Various alignment pins 172 may be disposed within certain components of the housing 22 for aligning certain components together. Specifically, the alignment of the port housing 108 with respect to the generating rotor 130, the pump body 132, and the pump cover 104 is used to ensure that the fluid 14 flows properly through each of the delivery portion 24 and the return portion 28 of the fluid pump 10. In addition to various O-rings 154 for separating certain portions of the fluid 14 within the delivery portion 24 and the return portion 28, the motor housing 160 may include a housing seal 174 for sealing the fluid pump 10 with respect to a specific manifold 176 of the drive unit 12.

[0062] like Figure 7-26, the spline assembly 220 of the drive shaft 34 includes a truncated end portion 230 of the spline assembly 220, which cooperates with the internal teeth 234 of the drive gear 202 and the gaps 232 between the internal gears 134 of the return pump element 26 and the delivery pump element 30, respectively. In this way, the engagement between the end portion 230 and the gap 232 defines axial flow chambers 236. These axial flow chambers 236 enable the fluid 14 to move axially along the drive shaft 34. Using these axial flow chambers 236, the fluid 14 can move along the spline assembly 220 and along the drive shaft 34 of the fluid pump 10. Additionally, the size of these axial flow chambers 236 is minimal so as not to reduce the suction force 72 and the repulsion force 76 generated by the operation of the return pump element 30 and the delivery pump element 26. .

[0063] Reference now Figure 1-8 15-26, the fluid pump 10 may include a housing 22 having a motor portion or motor housing 160, a delivery portion 24, and a return portion 28. The motor 32 is disposed within the motor housing 160 and is operably coupled to a drive shaft 34, which extends from the motor 32 and passes through the delivery portion 24 and the return portion 28. The delivery pump element 26 is disposed within the delivery portion 24 and coupled to the drive shaft 34. Similarly, the return pump element 30 is disposed within the return portion 28 and is also coupled to the drive shaft 34. Operation of the motor 32 drives the delivery pump element 26 and the return pump element 30 through the drive shaft 34. The delivery portion 24 and the delivery pump element 26 are configured to deliver the fluid 14 from the reservoir 18 to the drive unit 12. The return portion 28 and the return pump element 30 are configured to deliver the fluid 14 from the sump assembly 15 of the drive unit 12 and to the reservoir 18.

[0064] In certain aspects of the device, the reflux pump element 30 can be in the form of a gear pump 200 that includes a drive gear 202 coupled to the drive shaft 34. The gear pump 200 also includes opposing idler gears 204 that mesh with the drive gear 202. Each idler gear 204 cooperates with the drive gear 202 to create a dedicated suction area 72 that draws fluid 14 from one of the reservoirs 16 of the reservoir assembly 15. These opposing suction areas 72 cooperate to transport the fluid 14 from the first reservoir 50 and the second reservoir 52, respectively, and to the fluid pump 10. The engagement between the opposing idler gears 204 and the drive gear 202 also forms a dedicated repulsive force area 76 that discharges the fluid 14 from each respective reservoir 16 of the first reservoir 50 and the second reservoir 52 toward the dedicated outlet port 92 and the reflux outlet 100. In this manner, dedicated suction force region 72 and dedicated repulsive force region 76 operate to transfer fluid 14 from sump assembly 15 through return portion 28 of fluid pump 10 and to reservoir 18 .

[0065] like Figure 7-11 15-17, wherein the reflux pump element 30 is a gear pump 200, the gear pump 200 includes a drive gear 202 that meshes with at least one idle gear 204 to form dedicated meshing points 216. These dedicated meshing points 216 connect the reflux pump element 30 to the relative sump 16 of the sump assembly 15. Typically, each of the dedicated meshing points 216 corresponds to a respective sump 16 of the sump assembly 15. According to various aspects of the device, the gear pump 200 includes a plurality of meshing points 216. Each meshing point 216 of the plurality of meshing points 216 is configured to generate a suction force 72 to draw the fluid 14 from the sump assembly 15 to the reflux pump element 30. The meshing points 216 also generate a repulsive force 76 to transport the fluid from the reflux pump element 30 and to the reservoir 18. Additionally, each of the plurality of engagement points 216 of the gear pump 200 corresponds to a respective sump 16 of the sump assembly 15. As an example and not limitation, the sump assembly 15 may include a first sump 50 and a second sump 52 that correspond to a first engagement point 224 and a second engagement point 226 of the gear pump, respectively.

[0066] Reference again Figure 7-11 15-17, during operation of the motor 32, the drive shaft 34 operates each of the delivery pump element 26 and the return pump element 30. In the case of the gear pump 200, the drive shaft 34 rotates the drive gear 202 and the idler gear 204 within the pump chamber 206, and the pump chamber has a contoured profile that matches the arrangement of the drive gear 202 and the opposing idler gear 204. When the drive gear 202 and the idler gear 204 rotate within the pump chamber 206, the gear teeth 210 of the drive gear 202 and the idler gear 204 form a plurality of gear cavities 212 with the inner surface 214 of the pump chamber 206. These gear cavities 212 create dedicated suction areas 72 and dedicated repulsive areas 76. In this way, each gear cavity 212 delivers fluid 14 from the return inlet 54, which draws fluid 14 from the sump 16. As the drive gear 202 and the idler gear 204 rotate within the pump chamber 206 , the fluid 14 within the gear cavity 212 moves along the inner surface 214 of the pump chamber 206 and moves to the outlet port 92 of the return outlet 100 to be delivered to the reservoir 18 .

[0067] Reference again Figure 15-26According to various aspects of the device, the delivery inlet 120 and the delivery outlet 122 can be positioned to extend from the delivery pump element 26 and through the pump cover 104. Therefore, the delivery inlet 120, the delivery outlet 122, and the return inlet 54 and the return outlet 100 can each be positioned within the return surface 112 of the pump cover 104. In order to account for the movement of the fluid 14 through the delivery pump element 26 and the return pump element 30 through the pump cover 104, the pump chamber 206 can be positioned across the center of the pump cover 104. This central configuration of the pump chamber 206 also allows the drive gear 202 to be centrally positioned within the pump cover 104 to engage the drive shaft 34. The idler gear 204 is generally positioned in an offset orientation and is positioned on the opposite side of the pump cover 104 relative to the delivery inlet 120 and the delivery outlet 122.

[0068] Reference again Figure 1-26 , the fluid pump 10 may include a motor portion or motor housing 160, a delivery pump element 26 and a reflux pump element 30. A drive shaft 34 extends from the motor 32 to each of the delivery pump element 26 and the reflux pump element 30. The motor 32, the drive shaft 34, the delivery pump element 26 and the reflux pump element 30 are all contained within the housing 22. The operation of the motor 32 is configured to simultaneously drive the delivery pump element 26 and the reflux pump element 30 through the drive shaft 34. The delivery pump element 26 is configured to deliver and deliver the fluid 14 from the reservoir 18 to the drive unit 12. The reflux pump element 30 is configured to deliver and deliver the fluid 14 from the sump assembly 15 of the drive unit 12 to the reservoir 18 for later use. As described herein, the various configurations of the drive unit 12 and the fluid pump 10 can vary according to the design of the specific mechanism in which the fluid pump 10 is positioned. Therefore, the number of sump 16 in the sump assembly 15 and the design of the reflux pump element 30 can vary.

[0069] Reference now Figure 15-19, using the axial flow chamber 236 defined between the spline assembly 220 of the drive shaft 34 and the drive gear 202 and the internal gear 134 of the return pump element 30 and the delivery pump element 26, respectively, the fluid 14 can move along the drive shaft 34 and toward the PCB 162. Additionally, as the fluid 14 moves through the spline assembly 220 and toward the PCB 162, the circulation space 240 between the outer surface 242 of the rotor 40 and the inner surface 244 of the stator 38 can be used to transport the fluid 14 back toward the delivery portion 24 and the return portion 28 of the fluid pump 10. In this way, as the fluid 14 moves along the spline assembly 220 and toward the PCB 162, heat 88 from the motor 32 and the PCB 162 is absorbed by the fluid 14. The fluid 14 and the now absorbed heat 88 are transferred away from the motor 32 and away from the PCB 162 by the directional movement of the fluid 14. Then, the fluid 14 and the heat 88 return toward the delivery portion 24 through the circulation space 240. The fluid 14 may then be reintegrated into the main flow of the fluid 14 via the delivery portion 24 or the return portion 28 of the fluid pump 10 .

[0070] Additionally, the motor housing 160 may also include some heat removal mechanism 250, such as a heat sink, heat removal fins, or other heat conducting portion, which may be used to dissipate the heat 88 accumulated within the PCB 162. Using the heat removal mechanism 250 and the fluid 14 moving through the spline assembly 220 and the circulation space 240, the heat 88 may be extracted from the PCB 162 and moved to an area external to the fluid pump 10. In this manner, the PCB 162 and the motor 32 for the fluid pump 10 may be maintained within a specific temperature range.

[0071] In order to allow the fluid 14 to be re-integrated from the circulation space 240 near the PCB 162 and returned to the flow of fluid 14 through the delivery portion 24 of the fluid pump 10, one or more suction ports 260 may be defined near the delivery inlet 120 of the fluid pump 10. Thus, the suction 72 generated by the delivery pump element 26 not only draws the fluid 14 from the reservoir 18, but also draws the fluid 14 from the circulation space 240 within the motor housing 160. It is also contemplated that this fluid 14 from the motor housing 160 may be integrated into the remainder of the fluid 14 at other locations within the delivery portion 24 or return portion 28 of the fluid pump 10 and pass through the inlet fluid pump 10.

[0072] In certain aspects of the device, such as Figure 13-1621-22, the delivery pump element 26 may include a suction port 260 that allows for a dual-fill configuration. In this dual-fill configuration, the delivery pump element 26 may use suction 72 to draw the fluid 14 from the opposite side of the generating rotor 130 into the fluid chamber 138. With this configuration, the suction port 260 may also provide a path through which the fluid 14 may return from the circulation space 240 into the delivery portion 24 of the fluid pump 10.

[0073] In one aspect of the device, the fluid 14 from the motor housing 160 can be integrated from the circulation space 240 into the main flow of the fluid 14 at the delivery outlet 122 of the fluid pump 10, so that the pressure generated by the delivery pump element 26 pushes the fluid 14 from the delivery pump element 26 and the fluid 14 from the motor housing 160 toward the pump outlet and also toward the drive unit 12. This configuration of the fluid pump 10 is intended to promote continuous flow of the fluid 14 through the motor housing 160 to extract heat 88 from the PCB 162 and the motor 32 to maintain the motor 32 and the PCB 162 at a relatively stable temperature during operation of the fluid pump 10.

[0074] Reference now Figure 13-14 and 20, one of the drive gear 202 for the return pump element 30 and the pump body 132 for the delivery pump element 26 can include a bearing support 270 that extends along a dedicated portion of the drive shaft 34. As described herein, the engagement between the drive shaft 34 and these bearing supports 270 can at least partially define an axial flow cavity 236 that supports the flow of the fluid 14 along the spline assembly 220 and between the return portion 28, the delivery portion 24, and the motor housing 160. In addition, these bearing supports 270 provide axial support for the drive shaft 34 to minimize wear on the components of the motor 32 and the fluid pump 10. The bearing support 270 of the delivery pump element 26 is contained in the same pump body 132 as the delivery pump element 26. In this manner, the bearing support 270 of the pump body 132 defines a sleeve 272 through which the drive shaft 34 extends and passes through the internal gear 134 of the delivery pump element 26. Similarly, the bearing support 270 of the reflux pump element 30 is contained within the same port housing 108 in which the reflux pump element 30 is located. At least a portion of the bearing support 270 is defined within the drive gear 202 of the reflux pump element 30 and a portion of the port housing 108 that houses the reflux pump element 30. The port housing 108 defines a sleeve 272 surrounding the bearing support 270 of the drive gear 202. This configuration allows the bearing support 270 of the drive gear 202 to be installed within the sleeve 272 of the port housing 108. These bearing supports 270 provide multiple support points for the drive shaft 34 as it rotates within the fluid pump 10 and provide multiple fluid flow functions within the fluid pump 10 as described herein.

[0075] Reference again Figure 13-14 20, the configuration of the bearing bracket 270 of the delivery pump element 26 and the return pump element 30 allows the internal gear 134 of the rotor 130 and the drive gear 202 of the gear pump 200 to be aligned within the fluid pump 10 and the corresponding delivery portion 24 and return portion 28 of the housing 22. This configuration can be used to reduce the occurrence of component binding and over-constraint of the delivery pump element 26 and the return pump element 30. Additionally, this configuration also reduces the requirements for tight tolerances within and between components of the fluid pump 10.

[0076] Reference again Figure 21-26 10, a portion of the pump body 132 may include a pressure side port 280 located proximate the high pressure side of the delivery pump element 26. During operation of the motor 32, the pressure side port 280 delivers the fluid 14 toward the drive shaft 34. This movement of the fluid 14 allows the fluid 14 to move toward the drive shaft 34 and the spline assembly 220 of the drive shaft 34. The bore through the pump body 132 that receives and supports the drive shaft 34 may include an oil feed 282 that allows a minimum amount of the fluid 14 to move from the pressure side port 280 and along the spline assembly 220 and to the motor housing 160 and the delivery portion 24 and return portion 28 of the fluid pump 10.

[0077] Reference again Figure 15-16 , the spline assembly 220 of the drive shaft 34 extends through each of the delivery pump element 26 and the return pump element 30. As described herein, the spline assembly 220 is elongated to extend through both of these assemblies and also move the fluid 14 along the spline assembly 220 of the drive shaft 34. Through the spline assembly 220, a single motor 32 can rotate a single drive shaft 34, which operates multiple drive elements for completing the delivery and return functions of the fluid pump 10 as described herein.

[0078] The invention disclosed herein is further summarized in the following paragraphs and is further characterized by any and all combinations of the various aspects described therein.

[0079] According to one aspect of the present disclosure, a fluid pump includes a housing having a motor portion, a delivery portion, and a return portion. The motor is disposed in the motor portion. The motor is operably coupled to a drive shaft, which extends from the motor and passes through the delivery portion and the return portion. A delivery pump element is disposed in the delivery portion and coupled to the drive shaft. A return pump element is disposed in the return portion of the housing and coupled to the drive shaft, wherein the operation of the motor operates the delivery pump element and the return pump element through the drive shaft. The delivery pump element is configured to deliver fluid from a reservoir to a drive unit, and the return pump element is configured to deliver the fluid from a sump assembly of the drive unit to the reservoir.

[0080] According to yet another aspect, a portion of the fluid is delivered from the delivery pump element and along the splines of the drive shaft for lubricating the delivery pump element and the return pump element.

[0081] According to yet another aspect, the operation of the motor simultaneously operates the delivery pump element and the return pump element to transfer the fluid between the reservoir, the drive unit, and the sump assembly.

[0082] According to yet another aspect, the delivery pump element is a generating rotor.

[0083] According to yet another aspect, the tank assembly includes a plurality of tanks.

[0084] According to yet another aspect, the return pump element is a gear pump including a drive gear meshing with at least one idler gear.

[0085] According to yet another aspect, the drive shaft extends through and operatively engages an internal gear of the generating rotor for the delivery pump element and the drive gear of the gear pump for the return pump element.

[0086] According to another aspect, the delivery portion of the housing and the return portion of the housing each define a sleeve that surrounds a separate portion of the drive shaft and facilitates delivery of the fluid along the drive shaft.

[0087] According to yet another aspect, the delivery portion includes a pump body containing the delivery pump element, wherein the pump body includes a pressure side port located proximate a high pressure side of the delivery pump element for delivering the fluid toward the drive shaft.

[0088] According to yet another aspect, during the operation of the drive shaft, the delivery pump element delivers the fluid from the pressure-side port and along the splines of the drive shaft for lubricating at least the delivery pump element and the return pump element.

[0089] According to yet another aspect, the motor portion of the housing includes a heat removal mechanism that directs heat from a printed circuit board to an area external to the housing.

[0090] According to yet another aspect, the splines transport the fluid into the motor portion and at least around a rotor of the motor to absorb heat from the motor and a printed circuit board positioned in communication with the motor portion, and wherein the fluid and the heat are transported away from the motor portion.

[0091] According to yet another aspect, the gear pump includes a dedicated engagement point that places the return pump element in communication with a respective sump of the sump assembly, wherein the dedicated engagement point corresponds to the respective sump.

[0092] According to another aspect of the present disclosure, a fluid pump includes a housing, a motor disposed in a motor portion of the housing, a delivery pump element disposed in a delivery portion of the housing, and a return pump element disposed in a return portion of the housing. A drive shaft is coupled to each of the delivery pump element and the return pump element, and operation of the motor synchronously operates the delivery pump element and the return pump element through the drive shaft. The delivery pump element is configured to deliver fluid from a reservoir to a drive unit, and the return pump element is configured to deliver the fluid from a sump assembly of the drive unit to the reservoir.

[0093] According to yet another aspect, a portion of the fluid is delivered from the delivery pump element and along the splines of the drive shaft for lubricating the delivery pump element and the return pump element.

[0094] According to yet another aspect, the delivery pump element is a generating rotor.

[0095] According to yet another aspect, the tank assembly includes a plurality of tanks.

[0096] According to yet another aspect, the return pump element is a gear pump including a drive gear meshing with at least one idler gear.

[0097] According to yet another aspect, the gear pump includes a plurality of engagement points, each of the plurality of engagement points being configured to generate a suction force to draw the fluid from the sump assembly to the return pump element.

[0098] According to yet another aspect, each of the plurality of engagement points of the gear pump corresponds to a respective sump of the sump assembly.

[0099] According to yet another aspect, the drive unit includes a first tank and a second tank of the tank assembly, the first tank and the second tank corresponding to a first meshing point of the gear pump and a second meshing point of the gear pump, respectively.

[0100] According to yet another aspect, the drive shaft extends through and operatively engages an internal gear of a generating rotor for the delivery pump element and the drive gear of the gear pump for the return pump element.

[0101] According to yet another aspect, the delivery portion of the housing and the return portion of the housing each define a sleeve that surrounds a separate portion of the drive shaft and facilitates delivery of the fluid along the drive shaft.

[0102] According to yet another aspect, the delivery portion includes a pump body containing the delivery pump element, wherein the pump body includes a pressure side port located proximate a high pressure side of the delivery pump element for delivering the fluid toward the drive shaft.

[0103] According to yet another aspect, during the operation of the drive shaft, the delivery pump element delivers the fluid from the pressure-side port and along the splines of the drive shaft for lubricating at least the delivery pump element and the return pump element.

[0104] According to yet another aspect, the motor portion of the housing includes a heat removal mechanism that directs heat from a printed circuit board to an area external to the housing.

[0105] According to yet another aspect, the splines transport the fluid into the motor portion and at least around a generating rotor of the motor to absorb heat from the motor and a printed circuit board positioned in communication with the motor portion, and wherein the fluid and the heat are transported away from the motor portion.

[0106] According to yet another aspect, the gear pump includes a dedicated meshing point that connects the return pump element to the corresponding tank of the tank assembly, wherein the dedicated meshing point corresponds to the corresponding tank, and the corresponding tank corresponds between the corresponding tanks of the tank assembly.

[0107] According to yet another aspect, the fluid in the delivery portion of the housing is maintained separated from the fluid in the return portion of the housing.

[0108] According to another aspect of the present disclosure, a fluid pump includes a housing, a motor disposed in a motor portion of the housing, a delivery pump element disposed in a delivery portion of the housing, a return pump element disposed in a return portion of the housing, and a drive shaft having a spline. The drive shaft extends from the rotor of the motor to each of the delivery pump element and the return pump element. The operation of the motor operates the delivery pump element and the return pump element simultaneously through the drive shaft. The delivery pump element is configured to deliver fluid from a reservoir to a drive unit. The return pump element is configured to deliver the fluid from a sump assembly of the drive unit to the reservoir. During the operation of the motor, the spline delivers a portion of the fluid into the motor portion and at least around the rotor of the motor to absorb heat from the motor and a printed circuit board positioned to communicate with the motor portion.

[0109] According to yet another aspect, the operation of the transfer pump element transfers the portion of the fluid and collected heat away from the motor portion and through the transfer portion of the housing.

[0110] According to yet another aspect, wherein the splines also deliver the portion of the fluid for lubricating the delivery pump element and the return pump element.

[0111] According to yet another aspect, the delivery pump element is a generating rotor.

[0112] According to yet another aspect, the tank assembly includes a plurality of tanks.

[0113] According to yet another aspect, the return pump element is a gear pump including a drive gear meshing with at least one idler gear.

[0114] According to yet another aspect, the gear pump includes a plurality of engagement points, each of the plurality of engagement points being configured to generate a suction force to draw fluid from the sump assembly to the return pump element.

[0115] According to yet another aspect, each of the plurality of engagement points of the gear pump corresponds to a respective sump of the sump assembly.

[0116] According to yet another aspect, the drive unit includes a first tank and a second tank of the tank assembly, the first tank and the second tank corresponding to a first meshing point of the gear pump and a second meshing point of the gear pump, respectively.

[0117] According to yet another aspect, the drive shaft extends through and operatively engages an internal gear of the generating rotor for the delivery pump element and the drive gear of the gear pump for the return pump element.

[0118] According to another aspect, the delivery portion of the housing and the return portion of the housing each define a sleeve that surrounds a separate portion of the drive shaft and facilitates delivery of the fluid along the drive shaft.

[0119] According to yet another aspect, the delivery portion includes a pump body containing the delivery pump element, wherein the pump body includes a pressure side port located proximate a high pressure side of the delivery pump element for delivering the fluid toward the drive shaft.

[0120] According to yet another aspect, during the operation of the drive shaft, the delivery pump element delivers the fluid from the pressure-side port and along the splines of the drive shaft for lubricating at least the delivery pump element and the return pump element.

[0121] According to yet another aspect, the motor portion of the housing includes a heat removal mechanism that directs the heat from the printed circuit board to an area external to the housing.

[0122] It should be understood that changes and modifications may be made to the aforementioned structures without departing from the concepts of the present invention, and it should be further understood that such concepts are intended to be covered by the appended claims unless the wording of the claims explicitly states otherwise.

Claims

1. A fluid pump, comprising: A housing having a motor portion, a delivery portion, and a return portion; a motor disposed within the motor portion, the motor operably coupled to a drive shaft extending from the motor and through the delivery portion and the return portion; a delivery pump element disposed in the delivery portion and coupled to the drive shaft; as well as a reflux pump element disposed within the reflux portion of the housing and coupled to the drive shaft, wherein operation of the motor operates the delivery pump element and the reflux pump element via the drive shaft, wherein the delivery pump element is configured to deliver fluid from a reservoir to a drive unit, and wherein the reflux pump element is configured to deliver the fluid from a sump assembly of the drive unit to the reservoir.

2. The fluid pump of claim 1, wherein a portion of the fluid is delivered from the delivery pump element and along the splines of the drive shaft for lubricating the delivery pump element and the return pump element.

3. The fluid pump of any one of claims 1 to 2, wherein the operation of the motor simultaneously operates the delivery pump element and the return pump element to transfer the fluid between the reservoir, the drive unit, and the sump assembly.

4. The fluid pump according to any one of claims 1 to 3, wherein the delivery pump element is a generating rotor.

5. The fluid pump of any one of claims 1 to 4, wherein the sump assembly comprises a plurality of sump tanks.

6. A fluid pump according to any one of claims 4 to 5, wherein the return pump element is a gear pump comprising a drive gear meshing with at least one idler gear.

7. The fluid pump of claim 6, wherein the drive shaft extends through and operatively engages an internal gear of the generating rotor for the delivery pump element and the drive gear of the gear pump for the return pump element.

8. The fluid pump of any one of claims 1 to 7, wherein the delivery portion of the housing and the return portion of the housing each define a sleeve that surrounds a separate portion of the drive shaft and facilitates delivery of the fluid along the drive shaft.

9. A fluid pump according to any one of claims 1 to 2, wherein the delivery portion comprises a pump body, the pump body containing the delivery pump element, wherein the pump body comprises a pressure side port, the pressure side port being positioned close to the high pressure side of the delivery pump element for delivering the fluid toward the drive shaft.

10. The fluid pump of claim 9, wherein during the operation of the drive shaft, the delivery pump element delivers the fluid from the pressure side port and along the splines of the drive shaft for lubricating at least the delivery pump element and the return pump element.

11. The fluid pump of any one of claims 1 to 10, wherein the motor portion of the housing includes a heat removal mechanism that directs heat from a printed circuit board to an area external to the housing.

12. A fluid pump according to any one of claims 10 to 11, wherein the splines transport the fluid into the motor portion and at least around the rotor of the motor to absorb heat from the motor and a printed circuit board positioned in communication with the motor portion, and wherein the fluid and the heat are transported away from the motor portion.

13. The fluid pump of any one of claims 6 to 12, wherein the gear pump includes a dedicated engagement point that places the return pump element in communication with a respective sump of the sump assembly, wherein the dedicated engagement point corresponds to the respective sump.

14. A fluid pump, comprising: case; a motor disposed in a motor portion of the housing; a delivery pump element disposed within the delivery portion of the housing; and a reflux pump element disposed within the reflux portion of the housing, wherein a drive shaft is coupled to each of the delivery pump element and the reflux pump element, and wherein operation of the motor synchronously operates the delivery pump element and the reflux pump element via the drive shaft, wherein the delivery pump element is configured to deliver fluid from a reservoir to a drive unit, and wherein the reflux pump element is configured to deliver the fluid from a sump assembly of the drive unit to the reservoir.

15. The fluid pump of claim 14, wherein a portion of the fluid is delivered from the delivery pump element and along the splines of the drive shaft for lubricating the delivery pump element and the return pump element.

16. The fluid pump according to any one of claims 14 to 15, wherein the delivery pump element is a generating rotor.

17. A fluid pump according to any one of claims 14 to 16, wherein the sump assembly comprises a plurality of sump tanks.

18. A fluid pump according to any one of claims 14 to 17, wherein the return pump element is a gear pump comprising a drive gear meshing with at least one idler gear.

19. The fluid pump of claim 18, wherein the gear pump comprises a plurality of engagement points, each of the plurality of engagement points being configured to generate a suction force to draw the fluid from the sump assembly to the return pump element.

20. The fluid pump of claim 19, wherein each of the plurality of engagement points of the gear pump corresponds to a respective sump of the sump assembly.

21. The fluid pump according to any one of claims 18 to 20, wherein the drive unit comprises a first reservoir and a second reservoir of the reservoir assembly, the first reservoir and the second reservoir corresponding to a first meshing point of the gear pump and a second meshing point of the gear pump, respectively.

22. A fluid pump according to any one of claims 18 to 21, wherein the drive shaft extends through and operatively engages an internal gear of a generating rotor for the delivery pump element and the drive gear of the gear pump for the return pump element.

23. A fluid pump according to any one of claims 14 to 22, wherein the delivery portion of the housing and the return portion of the housing each define a sleeve that surrounds a separate portion of the drive shaft and facilitates delivery of the fluid along the drive shaft.

24. A fluid pump according to any one of claims 15 to 23, wherein the delivery portion comprises a pump body, the pump body containing the delivery pump element, wherein the pump body comprises a pressure side port, the pressure side port being positioned proximate to the high pressure side of the delivery pump element for delivering the fluid toward the drive shaft.

25. The fluid pump of claim 24, wherein during the operation of the drive shaft, the delivery pump element delivers the fluid from the pressure side port and along the splines of the drive shaft for lubricating at least the delivery pump element and the return pump element.

26. The fluid pump of any one of claims 14 to 25, wherein the motor portion of the housing includes a heat removal mechanism that directs heat from a printed circuit board to an area external to the housing.

27. A fluid pump according to any one of claims 15 to 26, wherein the splines transport the fluid into the motor portion and at least around a generating rotor of the motor to absorb heat from the motor and a printed circuit board positioned to communicate with the motor portion, and wherein the fluid and the heat are transported away from the motor portion.

28. A fluid pump according to any one of claims 18 to 27, wherein the gear pump includes a dedicated meshing point, which connects the return pump element to the corresponding tank of the tank assembly, wherein the dedicated meshing point corresponds to the corresponding tank, and the corresponding tank corresponds between the corresponding tanks of the tank assembly.

29. A fluid pump according to any one of claims 14 to 28, wherein the fluid in the delivery portion of the housing is maintained separate from the fluid in the return portion of the housing.

30. A fluid pump comprising: case; a motor disposed in a motor portion of the housing; a delivery pump element disposed within the delivery portion of the housing; a return pump element disposed within the return portion of the housing; a drive shaft having a spline extending from the rotor of the motor to each of the delivery pump element and the return pump element, wherein Operation of the motor synchronously operates the delivery pump element and the return pump element via the drive shaft; The transfer pump element is configured to transfer fluid from the reservoir to the drive unit; The return pump element is configured to transfer the fluid from the sump assembly of the drive unit to the reservoir; and During the operation of the motor, the splines deliver a portion of the fluid into the motor portion and at least around the rotor of the motor to absorb heat from the motor and a printed circuit board positioned in communication with the motor portion.

31. The fluid pump of claim 30, wherein the operation of the transfer pump element transfers the portion of the fluid and collected heat away from the motor portion and through the transfer portion of the housing.

32. A fluid pump according to any one of claims 30 to 31 , wherein the splines also convey the portion of the fluid for lubricating the delivery pump element and the return pump element.

33. A fluid pump according to any one of claims 30 to 32, wherein the delivery pump element is a generating rotor.

34. A fluid pump according to any one of claims 30 to 33, wherein the sump assembly comprises a plurality of sump tanks.

35. A fluid pump according to any one of claims 33 to 34, wherein the return pump element is a gear pump comprising a drive gear meshing with at least one idler gear.

36. The fluid pump of claim 35, wherein the gear pump comprises a plurality of engagement points, each of the plurality of engagement points being configured to generate a suction force to draw fluid from the sump assembly to the return pump element.

37. The fluid pump of claim 36, wherein each of the plurality of engagement points of the gear pump corresponds to a respective sump of the sump assembly.

38. The fluid pump according to any one of claims 35 to 37, wherein the drive unit comprises a first reservoir and a second reservoir of the reservoir assembly, the first reservoir and the second reservoir corresponding to a first meshing point of the gear pump and a second meshing point of the gear pump, respectively.

39. A fluid pump according to any one of claims 35 to 38, wherein the drive shaft extends through and operatively engages an internal gear of the generating rotor for the delivery pump element and the drive gear of the gear pump for the return pump element.

40. A fluid pump according to any one of claims 30 to 39, wherein the delivery portion of the housing and the return portion of the housing each define a sleeve that surrounds a separate portion of the drive shaft and facilitates delivery of the fluid along the drive shaft.

41. A fluid pump according to any one of claims 32 to 40, wherein the delivery portion comprises a pump body, the pump body containing the delivery pump element, wherein the pump body comprises a pressure side port, the pressure side port being positioned proximate to the high pressure side of the delivery pump element for delivering the fluid toward the drive shaft.

42. The fluid pump of claim 41, wherein during the operation of the drive shaft, the delivery pump element delivers the fluid from the pressure side port and along the splines of the drive shaft for lubricating at least the delivery pump element and the return pump element.

43. A fluid pump according to any one of claims 30 to 42, wherein the motor portion of the housing includes a heat removal mechanism that directs the heat from the printed circuit board to an area external to the housing.

Images