Patent Application
20250207604
The disclosure generally relates to electronically commutated fluid pumps and, more specifically, to electronically commutated fluid pumps for pumping fluids such as oil or fuel.
Electro-hydraulic pumps are electromechanical apparatuses in which mechanical energy generated by a motor is transferred to a hydraulic pump section that moves a fluid to provide fluid flow and fluid pressure in a hydraulic circuit. Examples of these pumps used in vehicles include gear pumps such as electronic fuel pumps (EFPs) that feed fuel from the fuel delivery module (FDM) in the fuel tank to a combustion engine of the vehicle. Other examples include electronic oil pumps that move hydraulic fluid to cool and lubricate the internal mechanisms of, for example, an integrated drive module (IDM), such as the drive motor and gear box of the IDM. These electronic pumps may be directly commutated (“brush”) pumps that are driven by a constant voltage signal or electronically commutated (“brushless”) pumps that are driven by dedicated pump controllers. Common electronically commutated pumps include a housing assembly that houses the electric motor and a pumping section such as a gerotor arrangement that is driven by the motor. A controller operates the motor to drive the pumping section to pump fluid from a reservoir to a desired vehicle system.
The use of electronically commutated pumps in the field of automotive vehicles has increased with the demand for greater vehicle fuel economy as well as greater drive range for electric vehicles (EVs). This demand requires that the pumps and systems that use them are more robust and efficient, while also offering these improvements at a lower cost. For example, the use of electronically commutated requires the pump controller to either be integrated into an existing control module (e.g., the engine control module (ECM), the powertrain control module (PCM), or the vehicle control module (VCM)), located in a separate standalone unit external to the pump or other control modules, or integrated directly into the pump. Configurations in which the controller is exposed to environmental elements and temperatures are challenging in regards to maintaining the useful life of the controller. Road or drive train vibration, extreme hot and cold environmental temperatures, thermal shock, humidity, high pressure, salt spray, and gravel bombardment are some of the hazards that are posed to controllers that are disposed under the vehicle hood or in other external carriage locations. As such, the sealing and venting of printed circuit board (PCB) controllers and related electronics is critical to ensuring proper pump life and function. Sealing of a PCB chamber in a controller assembly is typically accomplished with paper, rubber, or liquid silicon gaskets that are placed in position during assembly. The PCB chamber in the PCB assembly needs to be vented to account for changes in pressure due to gas build up (outgassing) from and around the electronic components. Passive ventilation uses non-mechanical design elements, such as ventilation holes cut into the chamber enclosure, to cool the PCB device, equalize pressure, and prevent condensation. Passive ventilation is typically used for ventilating smaller device enclosures having lower input power. Other ventilation systems include a ventilation hole that is covered with a plastic sticker after the PCB cavity has been relieved of any pressure that is built up, typically by energizing the PCB during assembly and testing to remove any gases trapped in the PCB cavity before the hole is closed and sealed. Once the hole is closed by the sticker or similar, the hole is sealed and prevents flow of gas. The lack of robustness of a hole covered by a sticker limits its use in harsh environmental conditions, and alternatively adding extra components to the ventilation system can be cost-prohibitive. Thus, proper ventilation of PCB chambers represents a potential cost increase in both product material and the assembly process. Therefore, a need exists for a PCB ventilation system that does not add additional elements or assembly steps to the system and that can withstand the environmental conditions experienced by a vehicle and its components. This is especially true for electronically commutated fluid pumps in which the controller is integrated into the pump.
An improved sealing arrangement for an electronically commutated fluid pump is provided. The sealing arrangement includes a housing including an outer face surface and an internal chamber. The outer face surface forms a perimeter that defines an opening into the chamber. An endless groove is formed in the outer face surface. The endless groove surrounds the perimeter and has an inward radial sealing surface, an opposite outward radial sealing surface, and a bottom axial sealing surface between the inward and outward radial sealing surfaces. A gland is formed in the outer face surface and is connected to the endless groove. The gland includes a vent passage and a sealing surface that defines a depression in the outer face surface of the housing. The vent passage connects the chamber in fluid communication with the depression. The sealing arrangement further includes a gasket including an endless body having an inner side surface, an outer side surface, a bottom surface, a top surface, a pair of inner and outer radially extending wings, and a venting element. The inner wing extends from the inner side surface of the body and the outer wing extends from the outer side surface of the body. The venting element protrudes from the outer side surface of the body and includes a lip. The lip extends upwardly and outwardly from the bottom surface of the body. The gasket is received in the endless groove such that the venting element is disposed in the gland, the inner wing of the gasket engages the inward radial sealing surface of the endless groove, and the outer wing of the gasket engages the outward radial sealing surface of the endless groove. The venting element is movable between a closed position in which the lip of the venting element seals against the sealing surface of the gland and an open position in which the lip is spaced from the sealing surface to allow for communication of fluid from the housing chamber to outside of the housing. The venting element is in the closed position when an external pressure outside of the housing is greater than an internal pressure in the housing chamber, and the venting element is in the open position when the internal pressure in the housing chamber is greater than the external pressure outside of the housing.
In specific embodiments, the vent passage is a groove transverse to the endless groove.
In particular embodiments, the vent passage groove extends from a wall of the chamber housing through the endless groove to the sealing surface of the gland.
In particular embodiments, the vent passage groove is formed in the outer face surface of the housing, the endless groove, and the sealing surface.
In specific embodiments, the venting element includes a pair of sidewalls disposed at opposite ends of the lip.
In particular embodiments, a pocket is formed between the lip of the venting element, the sidewalls of the venting element, and the outer side surface of the body.
In specific embodiments, the venting element includes at least one rib formed on a back surface of the lip.
In specific embodiments, the inner wing of the gasket has a break adjacent the venting element, and the break is aligned with the vent passage of the gland.
An integrated controller assembly for an electronically commutated fluid pump is also provided. The integrated controller assembly includes a housing including an outer face surface and an internal chamber. The outer face surface forms a perimeter that defines an opening into the chamber. A printed circuit board is received in the chamber. Electrical terminals are connected to the printed circuit board and extend through the housing. A heat sink is mounted against the outer face surface of the housing and covers the opening in the housing. An endless groove is formed in the outer face surface of the housing. The endless groove surrounds the perimeter and has an inward radial sealing surface, an opposite outward radial sealing surface, and a bottom axial sealing surface between the inward and outward radial sealing surfaces. A gland is formed in the outer face surface and is connected to the endless groove. The gland includes a vent passage and a sealing surface that defines a depression in the outer face surface of the housing. The vent passage connects the chamber in fluid communication with the depression. The assembly further includes a gasket including an endless body having an inner side surface, an outer side surface, a bottom surface, a top surface, a pair of inner and outer radially extending wings, and a venting element. The inner wing extends from the inner side surface of the body and the outer wing extends from the outer side surface of the body. The venting element protrudes from the outer side surface of the body and includes a lip. The lip extends upwardly and outwardly from the bottom surface of the body. The gasket is received in the endless groove such that the venting element is disposed in the gland, the inner wing of the gasket engages the inward radial sealing surface of the endless groove, the outer wing of the gasket engages the outward radial sealing surface of the endless groove, and the top surface of the gasket engages the heat sink. The venting element is movable between a closed position in which the lip of the venting element seals against the sealing surface of the gland and an open position in which the lip is spaced from the sealing surface to allow for communication of fluid from the housing chamber to outside of the housing. The venting element is in the closed position when an external pressure outside of the housing is greater than an internal pressure in the housing chamber, and the venting element is in the open position when the internal pressure in the housing chamber is greater than the external pressure outside of the housing.
In specific embodiments, the vent passage is a groove transverse to the endless groove.
In specific embodiments, the venting element includes a pair of sidewalls disposed at opposite ends of the lip.
In particular embodiments, a pocket is formed between the lip of the venting element, the sidewalls of the venting element, and the outer side surface of the body.
In specific embodiments, the inner wing of the gasket has a break adjacent the venting element, and the break is aligned with the vent passage of the gland.
An electronically commutated fluid pump is also provided. The fluid pump includes a main housing, a pumping section disposed within the main housing, a motor disposed within the main housing and operatively connected to the pumping section, and an integrated controller assembly mounted on the main housing. The integrated controller assembly includes a housing including an outer face surface and an internal chamber. The outer face surface forms a perimeter that defines an opening into the chamber. A printed circuit board is received in the chamber. Electrical terminals are connected to the printed circuit board and extend through the housing. A heat sink is mounted against the outer face surface of the housing and covers the opening in the housing. An endless groove is formed in the outer face surface of the housing. The endless groove surrounds the perimeter and has an inward radial sealing surface, an opposite outward radial sealing surface, and a bottom axial sealing surface between the inward and outward radial sealing surfaces. A gland is formed in the outer face surface and is connected to the endless groove. The gland includes a vent passage and a sealing surface that defines a depression in the outer face surface of the housing. The vent passage connects the chamber in fluid communication with the depression. The assembly further includes a gasket including an endless body having an inner side surface, an outer side surface, a bottom surface, a top surface, a pair of inner and outer radially extending wings, and a venting element. The inner wing extends from the inner side surface of the body and the outer wing extends from the outer side surface of the body. The venting element protrudes from the outer side surface of the body and includes a lip. The lip extends upwardly and outwardly from the bottom surface of the body. The gasket is received in the endless groove such that the venting element is disposed in the gland, the inner wing of the gasket engages the inward radial sealing surface of the endless groove, the outer wing of the gasket engages the outward radial sealing surface of the endless groove, and the top surface of the gasket engages the heat sink. The venting element is movable between a closed position in which the lip of the venting element seals against the sealing surface of the gland and an open position in which the lip is spaced from the sealing surface to allow for communication of fluid from the housing chamber to outside of the housing. The venting element is in the closed position when an external pressure outside of the housing is greater than an internal pressure in the housing chamber, and the venting element is in the open position when the internal pressure in the housing chamber is greater than the external pressure outside of the housing.
In specific embodiments, the vent passage is a groove transverse to the endless groove.
In particular embodiments, the vent passage groove extends from a wall of the chamber housing through the endless groove to the sealing surface of the gland.
In particular embodiments, the vent passage groove is formed in the outer face surface of the housing, the endless groove, and the sealing surface.
In specific embodiments, the venting element includes a pair of sidewalls disposed at opposite ends of the lip.
In specific embodiments, a pocket is formed between the lip of the venting element, the sidewalls of the venting element, and the outer side surface of the body.
In specific embodiments, the inner wing of the gasket has a break adjacent the venting element, and the break is aligned with the vent passage of the gland.
Various advantages and aspects of this disclosure may be understood in view of the following detailed description when considered in connection with the accompanying drawings, wherein:
An electronically commutated fluid pump is provided. Referring to
With reference to
The motor section 18 includes an electric motor 24 which is disposed within the main housing 16. The electric motor 24 is, for example, an electronically commutated (EC) brushless motor. Electric motor 24 includes a shaft 26 extending therefrom into the pumping section 20. The motor 24 is thereby operatively connected to the pumping section 20. A permanent magnet rotor 28 is attached at an opposite end of the shaft 26, and the rotor 28 is surrounded by a stator 30. Shaft 26 rotates when an electric current is applied to the stator 30 of the electric motor 24. Electric motors, pumping sections, and their operation are well known, consequently, electric motor 24 and pumping section 20 will not be discussed further herein.
With continued reference to
In order to seal the internal chamber 44 in which the PCB 48 is located, a gasket 56 is disposed between the interface of the heat sink 54 and the housing 34. However, to release pressure in the sealed chamber 44 due to gas build-up (outgassing) from and around the electronic components of the PCB 48, the housing 34 and gasket 56 of the integrated controller assembly 32 together provide a passive ventilation sealing arrangement 58 that relieves pressure build-up in the chamber 44. With continued reference to
The gasket 56 is formed of an endless body 72 having an inner side surface 73a, an outer side surface 73b, a bottom surface 73c, and a top surface 73d. The gasket body 72 generally has a rectangular cross-sectional shape, but is not limited to such a cross-section, and the overall shape of the gasket 56 corresponds to the shape of the groove 60 in the outer face surface 40 of the housing 34 so that the gasket 56 can be inserted into the groove 60. For example, both may have a corresponding quadrilateral shape with curved corners. An inner radially extending wing 74a extends inwardly from the inner side surface 73a of the body 72, and similarly an outer radially extending wing 74b extends outwardly from the outer side surface 73b of the body 72. The wings 74a, 74b generally extend continuously around the perimeter of the gasket 56, but there is a break 74c in the inner wing 74a as described in more detail below. Each of the pair of wings 74a, 74b are significantly shorter in height than the height of the gasket 56 from the bottom surface 73c to the top surface 73d, such as less than a quarter of the height of the gasket, alternatively less than one-fifth the height of the gasket, and extend outwardly less than a quarter of the width of the gasket from the inner surface 73a to the outer surface 73b, alternatively less than one-fifth the width of the gasket, alternatively less than one-sixth the width of the gasket. The wings 74a, 74b may have an arcuate (e.g., semi-circular) cross-section, or alternatively may have a square, rectangular, or triangular cross-section. The wings 74a, 74b are generally centered between the bottom surface 73c and top surface 73d of the gasket 56, but alternatively may be offset from center. A venting element 75 protrudes from the outer side surface 73b. The venting element 75 includes a lip 76 that is curved and that extends upwardly and outwardly from the bottom surface 73c, and a sidewall 77 at each of the two opposite ends of the curved lip 76. However, it should be understood that the lip may have a combination of a curved and straight shape, or alternatively may have a combination of a straight and angled shape. A curved-shaped lip is only one embodiment of the venting element 75. A pocket 78 is formed between the curved lip 76 of the venting element 75, the sidewalls 77, and the outer side surface 73b of the body 72. The pocket 78 aides in the flexing of the curved lip 76 as described in more detail below. At least one rib, in this case three ribs 79, are formed on a back surface of the curved lip 76. The ribs 79 support the curved lip 76 and may control the degree of flexing of the curved lip.
When the gasket 56 is assembled into the groove 60 in the housing outer face surface 40, the venting element 75 fits into the depression 70 of the gland 64. The venting element 75 thereby serves as a locating feature that assures proper orientation of the gasket 56 in the groove 60. The curved lip 76 rests adjacent to the sealing surface 68 of the gland 64 and thus generally corresponds in shape to the sealing surface. Further, the outer edge of the curved lip 76 stops short of reaching the outer face surface 40 and therefore does not extend out of the gland 64. The break 74c in the inner wing 74a of the gasket 56 is adjacent the gasket venting element 75, and thus in the assembled disposition the break 74c is aligned with the vent passage 66 of the gland 64. With the heat sink 54 subsequently mounted on the housing 34, the heat sink 54 engages and compresses the gasket 56 into the groove 56. Thus, the inner wing 74a of the gasket 56 engages and provides a radial compression seal against the inward sealing surface 62a of the groove 60, the outer wing 74b of the gasket 56 engages and provides a radial compression seal against the outward sealing surface 62b of the groove 60, and the bottom surface 73c of the gasket 56 engages and provides an axial compression seal against the bottom surface 62b of the groove 60 to the seal the internal chamber and prevent fluid flow through the interface of the heat sink 54 and housing 34. However, the sealing arrangement 58 formed by the gland 64 and venting element 75 passively allows for both sealing of the internal chamber 44 of the housing 34 and venting of fluid (e.g., gases) when necessary.
As shown particularly in
Turning to
It is to be understood that the appended claims are not limited to express and particular compounds, compositions, or methods described in the detailed description, which may vary between particular embodiments which fall within the scope of the appended claims. With respect to any Markush groups relied upon herein for describing particular features or aspects of various embodiments, different, special, and/or unexpected results may be obtained from each member of the respective Markush group independent from all other Markush members. Each member of a Markush group may be relied upon individually and or in combination and provides adequate support for specific embodiments within the scope of the appended claims.
Further, any ranges and subranges relied upon in describing various embodiments of the present invention independently and collectively fall within the scope of the appended claims, and are understood to describe and contemplate all ranges including whole and/or fractional values therein, even if such values are not expressly written herein. One of skill in the art readily recognizes that the enumerated ranges and subranges sufficiently describe and enable various embodiments of the present invention, and such ranges and subranges may be further delineated into relevant halves, thirds, quarters, fifths, and so on. As just one example, a range “of from 0.1 to 0.9” may be further delineated into a lower third, i.e., from 0.1 to 0.3, a middle third, i.e., from 0.4 to 0.6, and an upper third, i.e., from 0.7 to 0.9, which individually and collectively are within the scope of the appended claims, and may be relied upon individually and/or collectively and provide adequate support for specific embodiments within the scope of the appended claims. In addition, with respect to the language which defines or modifies a range, such as “at least,” “greater than,” “less than,” “no more than,” and the like, it is to be understood that such language includes subranges and/or an upper or lower limit. As another example, a range of “at least 10” inherently includes a subrange of from at least 10 to 35, a subrange of from at least 10 to 25, a subrange of from 25 to 35, and so on, and each subrange may be relied upon individually and/or collectively and provides adequate support for specific embodiments within the scope of the appended claims. Finally, an individual number within a disclosed range may be relied upon and provides adequate support for specific embodiments within the scope of the appended claims. For example, a range “of from 1 to 9” includes various individual integers, such as 3, as well as individual numbers including a decimal point (or fraction), such as 4.1, which may be relied upon and provide adequate support for specific embodiments within the scope of the appended claims.
The above description is that of current embodiments of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. This disclosure is presented for illustrative purposes and should not be interpreted as an exhaustive description of all embodiments of the invention or to limit the scope of the claims to the specific elements illustrated or described in connection with these embodiments. For example, and without limitation, any individual element(s) of the described invention may be replaced by alternative elements that provide substantially similar functionality or otherwise provide adequate operation. This includes, for example, presently known alternative elements, such as those that might be currently known to one skilled in the art, and alternative elements that may be developed in the future, such as those that one skilled in the art might, upon development, recognize as an alternative. Further, the disclosed embodiments include a plurality of features that are described in concert and that might cooperatively provide a collection of benefits. The present invention is not limited to only those embodiments that include all of these features or that provide all of the stated benefits, except to the extent otherwise expressly set forth in the issued claims. Any reference to claim elements by ordinal terms, for example “first,” “second,” and “third,” are used for clarity, and are not to be construed as limiting the order in which the claim elements appear. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular.
