Patent Application
20210164427
The present disclosure relates generally to an adapter for a fuel pump.
Fuel systems for combustion engines can sometimes include a fuel pump assembly that pumps fuel from a fuel tank to an engine. The fuel pump generally is carried by some structure either within or outside of the fuel tank. Fuel is taken into the fuel pump through an inlet, the pressure of the fuel is increased, and the fuel is discharged from the fuel pump and delivered to the engine. Among other things, the size of various components of the fuel pump and a container or bracket in or on which the fuel pump is received may vary across a production run of these components. The coupling between such components may be looser or tighter as a result and vibrations may occur which may be audible and/or may affect the integrity of the coupling or the longevity of certain components.
In at least some implementations, an adapter, for a fuel pump having a casing, has a base having an axis and an opening through which fluid may flow, and multiple tabs connected to the base. The tabs are circumferentially spaced apart with a void between at least part of the tabs, and at least two tabs have a contact portion that extends radially inwardly to define a minimum diameter opening between the tabs. Each contact portion extends along a portion less than all of the surface areas of the radially inner surface of the tabs.
In at least some implementations, a radially outer surface at least a portion of which defines a maximum radial dimension of the adapter when the tabs are in an unflexed or at rest position. In at least some implementations, a flexible ring is carried by the adapter and extends radially outwardly from at least a portion of the adapter. The adapter may define a fuel pump receiving area between an inner surface of the base and the inner surface of the tabs, and the ring may be separate from the fuel pump receiving area.
In at least some implementations, the contact portions extend between 5% and 90% of the circumference of a circle bounded by the contact portions. Each contact portion may have an inner surface arranged to engage a fuel pump received between the tabs and the inner surface may have a surface area of less than 400 mm2.
In at least some implementations, each of the at least two tabs with a contact portion has a first portion connected to the base and a second portion that extends from the first portion to an end of the tab, the at least two tabs having a portion that extends radially outwardly to define a maximum outer dimension of the adapter and a portion that extends radially inwardly to the contact portions. The at least two tabs may be flexible and resilient and may be radially inwardly flexed.
In at least some implementations, a fuel pump assembly includes a fuel pump having a casing with an inlet through which fuel enters the casing, and a pumping element received within the casing, and an adapter received around at least part of the casing. The adapter has a base that is received adjacent to the inlet, an axis, an opening in communication with the inlet, and multiple tabs connected to the base. The tabs are circumferentially spaced apart with a void between at least part of two adjacent ones of the tabs, and wherein at least two tabs have an inner surface with a contact portion engaged with the casing and a portion that is spaced radially outwardly from the casing.
In at least some implementations, the contact portions extend between 5% and 90% of the circumference of a circle bounded by the contact portions. In at least some implementations, each contact portion has an inner surface arranged to engage a fuel pump received between the tabs and the inner surface has a surface area of less than 400 mm2.
In at least some implementations, each of the at least two tabs has a first portion connected to the base and a second portion that extends from the first portion to an end of the tab, the at least two tabs may have a portion that extends radially outwardly to define a maximum outer dimension of the adapter and a portion that extends radially inwardly to the contact portions. In at least some implementations, the at least two tabs are flexible and resilient and may be radially inwardly flexed. In at least some implementations, a container is provided that has a cavity in which the fuel pump and the adapter are at least partially received, and wherein the cavity having an inner dimension that is less than the maximum outer dimension of the adapter, and wherein at least some of the tabs are flexed inwardly when the adapter is received in the cavity.
In at least some implementations, a container is provided that has a cavity in which the fuel pump is at least partially received, the cavity is defined at least in part by an inner surface of the container, and wherein an outer surface of at least two tabs engages the container inner surface. The area of engagement between the outer surface of the tabs and the container inner surface may be axially spaced from the contact portions of the tabs. And the at least two tabs may extend axially from the base and each of the at least two tabs may engage the container along less than all of the axial length of the outer surface, and each of the at least two tabs may engage the casing along less than all of the axial length of the inner surface.
In at least some implementations, a container is provided that has a cavity in which the fuel pump is at least partially received, the cavity defined at least in part by an inner surface of the container, and a flexible ring is carried by the adapter and extends radially outwardly from at least a portion of the adapter and is engaged with the container inner surface. In at least some implementations, at least some of the tabs do not engage the container inner surface. In at least some implementations, the contact portions are defined by protrusions that extend inwardly from the tabs having the contact portions.
The various features set forth in the summary may be used in various combinations such that certain embodiments include all or less than all of the complementary or not mutually exclusive features set forth above and described further below.
The following detailed description of certain embodiments and best mode will be set forth with reference to the accompanying drawings, in which:
Referring in more detail to the drawings,
As shown in
An adapter 34, as shown in
The adapter 34 may have a base 38 and two or more tabs 40 extending from the base to free ends 42 spaced from the base. The tabs 40 may be separated by intervening voids 44 so that the free ends 42 of the tabs are independent of each other and the tabs may flex independently relative to the base 38. With a fuel pump 10 having a cylindrical casing 20, the base 38 may be generally circular and the tabs 40 may extend generally axially from the base 38 and may flex inwardly toward an axis 46 (
The outer diameter defined by the outer surface 50 of the tabs 40 may be greater than the outer diameter of the base 38, wherein a portion of the tabs 40 extend radially outwardly relative to the base 38 along the axial length of the tabs. In at least some implementations, the tabs 40 are not parallel to the outer surface of the casing 20 when installed on the fuel pump 10. In the implementation shown in
A limited area of contact (best shown in
Still further, in at least some implementations, flow areas are defined between the tabs 40 and the fuel pump casing 20 surrounding the contact portion of each tab 40 (e.g. above and below and around left and right sides of the contact areas in the orientation of the adapter 34 shown in the drawings). Accordingly, fluids are not likely to be trapped against the pump 10 about any significant surface area which, for example, may reduce the likelihood of corrosion of the pump casing 20 (e.g. due to water or other contaminants or corrosive things in the fuel of fuel system).
The base 38 may include an inlet opening 60 that is communicated with the container port 30 and with the fuel pump inlet 14 so that fuel that flows through the container port can flow to the fuel pump inlet and thereafter be pumped by the pump 10. The inlet opening 60 may include or be defined by an annular, axially extending projection 62 adapted to be received adjacent to or partially within the fuel pump inlet 14 (e.g. formed in the inlet body 22 of the fuel pump housing 16). In at least some implementations, the projection 62 may provide a seal with the fuel pump 10 to improve fuel flow to the fuel pump inlet 14. The container 12 may include a reservoir in which fuel is contained, and the port 30 in the container 12 may communicate the cavity 28 with the reservoir rather than the fuel tank so that fuel within the reservoir is communicated with the fuel pump 10. A separate inlet may be provided in the container through which fuel from a fuel supply (e.g. tank) is provided into the reservoir. Of course, these are just representative arrangements for the container 12 and fuel pump 10 and other arrangements may be used as desired.
To filter fuel before the fuel enters the fuel pump 10, the adapter 34 may include or carry a filter or screen 64. In at least some implementations, the screen 64 is carried by the adapter 34 and covers the inlet opening 60. In the embodiment shown, the screen 64 is coupled to the base 38 and is received between the base and the container wall 27 that is adjacent to the base. The screen 64 may include a periphery that is pressed into a groove in the adapter 34, or radially overlapped by one or more fingers, catches or latches of the adapter. Or the base 38 may include a knob 66 and the screen 64 may include an opening 68 (
The engagement of the flexible tabs 40 with the wall(s) 26 defining the cavity 28 may orient and/or retain the fuel pump 10 within the cavity 28, may reduce vibrations between the fuel pump 10 and container 28, and may do so even if the size of the cavity 28 varies within the range of flexibility of the tabs 40, such as may occur due to tolerances within a production run of containers 12 and a production run of fuel pumps 10 (e.g. fuel pump casings). The adapter 34 may be formed from a relatively soft material to damp vibrations, and from a material that is sufficiently flexible and resilient for the yieldable engagement with the container 12, and suitable for use in the fuels with which the container may be used. Representative but not limiting examples of materials from which the adapter 34 may be made include: various grades of Acetal (POM) or Nylon (PA). Materials may include mineral or fiber reinforcement to modify the stiffness or flexibility of the material to accommodate different vibration loading conditions which may be encountered in different applications.
Further, the limited surface area of contact between the adapter 34 and the fuel pump 10 reduce the areas wherein water or other contaminants may collect against the fuel pump housing 16 and corrode or otherwise foul the fuel pump 10, such as sometimes may occur when water is allowed to enter the fuel system and is in close contact between a rubber grommet or seal that is directly against and in contact with the fuel pump casing 20, which is often formed of a metal such as aluminum or steel. Here, the tabs 40 engage the pump casing 20 over a limited surface area, and in at least some implementations are not formed from a rubber or elastomer, and flow areas are defined around the contact portions of the tabs 40 so that no or less fluid is trapped against the pump casing 20.
If desired, a seal or grommet may still be used about the exterior of the adapter 34 between the adapter and the container 12. In at least some implementations, the seal or grommet does not directly engage the fuel pump 10. The seal may be carried by the container or adapter and surround the base axially spaced from the tabs 40 and voids 44 between the tabs, to engage the adapter 34 and the container wall(s) 26 and provide additional vibration damping between the adapter and container.
An example of an elastomeric ring 80 received around an adapter 82 and extending outwardly from a perimeter of the base 84 to engage the container 12 in assembly is shown in
In the implementation shown, the bottom of the fuel pump 10 engages the base 84 and the base 84 engages the container 12, but the sidewall of the pump casing 20 engages the tabs 86 which do not directly engage the container walls 26 such that the sidewall of the pump casing 20 is isolated or separated from the container 12 by a fluid gap between the adapter tabs 86 and the container wall(s) 26. To further reduce fluid from being trapped between the adapter 82 and the casing 20 and/or to reduce the amount of material used to form the adapter 82, the tabs 86 may include one or more openings 94 therethrough, for example, in portions of the tabs 86 that do not engage the pump casing 20.
In this example, the periphery of the adapter base 84 does not engage the container 12. To isolate the adapter 82 from the container 12 and damp vibrations between them, the flexible ring 80 may be received around part of the adapter 82 as noted above, for example, the periphery of the base 84. The ring 80 extends radially outwardly from the periphery of the base 84 and is compressed between the adapter 82 and container 12 in assembly. This may also provide a seal between the adapter 82 and container 12 that prevents contaminants from bypassing the screen 64, ensuring that all fluid that enters the pump 10 has passed through the screen 64. The ring 80 may engage the bottom wall 27 of the cavity 28, or feet 96 may extend axially beyond the ring 80 and engage the wall 27. The adapter 82 defines a fuel pump receiving area between the inner surface 98 of the base 84 and the inner surface 99 of the tabs 86, and in at least some implementations, the ring 80 is separate from the fuel pump receiving area so that the ring 80 does not directly engage the fuel pump 10 received in the adapter 82. The ring 80 may be formed from any suitable material, including flexible and resilient materials like elastomers suitable for use in fuels with which the adapter 82 may be used, such as but not limited to, nitrile (NBR) or fluorocarbon (FKM) rubber. The adapter 82 may be otherwise similar to the adapter 34, and the same reference numerals applied to the adapter in
A ring 80 may extend outwardly from the adapter 100 to be compressed between the adapter and container 12 in assembly. The ring 80 may be constructed and arranged as set forth with regard to adapter 82. Likewise, a filter or screen 64 may be carried by the adapter 100 to remove at least some contaminants from the fuel before the fuel is taken in by the fuel pump 10.
Thus, the adapters 34, 82, 100 provide an interface between the fuel pump 10 and the container 12 in which the fuel pump is received. In at least some implementations, to flexibly receive fuel pumps 10 having casings 20 of different dimensions, the adapter 34, 82, 100 may include multiple flexible tabs 40, 86 adapted to engage the fuel pump casing 20. At least two tabs 40, 86 may include a contact portion (e.g. end portion, protrusion, rib, etc.) that extends radially inwardly relative to another portion of the tab inner surface and the contact portions define a minimum opening dimension between the inner surface of the tabs 40, 86, where the minimum opening dimension is less than the dimension of the corresponding portion of the fuel pump casing 20 so that at least the tabs 40, 86 with the contact portions are flexed outwardly when the pump 10 is received within the adapter 34, 82, 100. The contact portions may have an inner surface facing the fuel pump receiving area and arranged to engage the fuel pump casing 20 over a limited contact area that is less than the area of the inside surfaces of the tabs, and flow areas may be provided around multiple sides or portions of the contact area to reduce fluids being trapped between the adapter 34, 82, 100 and pump casing 20. In at least some implementations, the contact area between the adapter and the pump casing is between 40 mm2 and 400 mm2, and the contact area spans less than 90% of the circumference of the pump casing.
In at least some implementations, to positively retain the position of the fuel pump 10 and adapter 34, 82, 100 relative to the container 12, the adapter may include a portion of a size equal to or slightly greater than the corresponding cavity 28 of the container 12 to provide a close fit or interference fit between them. In assembly, one or more flexible features, such as a tab 40 or ring 80, may engage the container 12 to damp vibrations between the pump 10 and container 12. To filter fuel before it enters the fuel pump, a screen 64 or adapter may be located upstream of the fuel pump inlet 14, may be carried by the adapter 34, 82, 100 and may be provided within a sealed chamber located between the adapter and container 12. The filter or screen 64 may be carried by the adapter 34, 82, 100, such as by a press-fit or interference fit of a portion of the screen with a portion of the adapter.
The forms of the invention herein disclosed constitute presently preferred embodiments and many other forms and embodiments are possible. It is not intended herein to mention all the possible equivalent forms or ramifications of the invention. It is understood that the terms used herein are merely descriptive, rather than limiting, and that various changes may be made without departing from the spirit or scope of the invention.
This application claims the benefit of U.S. Provisional Application Ser. No. 62/509,224 filed on May 22, 2017, the entire contents of which are incorporated herein by reference in their entireties.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US18/33838 | 5/22/2018 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62509224 | May 2017 | US |
