Patent Application
20210277902
This invention relates pump systems, and particularly pump systems used in connection with modern day jet engine fuel systems.
Centrifugal type fuel pumps are ideal for application in a modern day jet engine fuel system if the limitation of starting the engine is properly addressed. A centrifugal pump produces pressure as a function of the rotating speed squared. In a typical centrifugal pump application, insufficient pump output pressure is generated to start the engine when the pump is rotated at typical starting speeds (i.e., less than around 20 to 30% of operating speed where operating speed is, for example, from about 20,000 revolutions per minute (rpm) to about 40,000 rpm and thus starting speed may range from about 4000 rpm to about 12,000 rpm).
During operation of the engine, occasionally a need exists for actuation of a downstream device. Current fuel systems use multiple pumps for engine starting, normal operation (run mode), and actuation. As will be appreciated, multiple pumps add significantly to the overall size and/or weight of the fuel system. Use of a regenerative pumping element, particularly for start-up in a high-speed centrifugal fuel pump system is generally known in the art, for example as shown and described in commonly owned WO 2017/079309 A1 and US 2019/0277233 A1, the entire disclosures of which are hereby expressly incorporated herein by reference.
It would be desirable for a simplified arrangement to direct pressurized flow from the high-speed centrifugal pump while reducing sizing of various system components. Further, it would be advantageous if a single pump could provide the desired output for start-up, run, and actuation modes of a pump system in a compact, efficient manner.
A need exists for an improved arrangement that provides at least one or more of the above-described features, as well as satisfying still other features and benefits.
A fuel pump system for supplying fuel from an associated fluid source to an associated downstream use(s) including for engine (i) start mode, (ii) run mode, and (iii) actuation mode is disclosed herein.
In a preferred arrangement, the fuel pump system includes a pump including a primary stage having an inlet and an outlet that are configured to selectively supply pressurized flow for the (ii) run mode. A regenerative stage is commonly driven with the primary stage to selectively provide pressurized fluid for the (i) start mode and the (iii) actuation mode.
The fuel pump system may include a control valve, a regenerative stage control valve, and a pressure regulator valve, where the control valve is in communication with the primary stage for controlling operation thereof.
The fuel pump system may include the control valve in communication with the pressure regulator valve to selectively control fluid flow to the regenerative stage.
The fuel pump system may include the regenerative stage control valve selectively controlling fluid flow from the regenerative stage for the (i) start mode.
The fuel pump system may include the regenerative stage control valve in fluid communication with the outlet of the primary stage such that the regenerative stage control valve selectively closes in response to a preselected pressure at the primary stage outlet.
In a preferred arrangement of the fuel pump system, the pressure regulator valve and the regenerative stage control valve are both open during the (i) start mode.
The pressure regulator valve and the regenerative stage control valve may both be closed during the (ii) run mode.
In a preferred arrangement, the pressure regulator valve is open and the regenerative stage control valve is closed during the (iii) actuation mode.
A first check valve may be provided downstream of the primary stage outlet.
The first check valve may be closed during the (i) start mode.
The first check valve may be open during the (ii) run mode and the (iii) actuation mode.
A second check valve may be provided downstream of the regenerative stage.
The second check valve may be closed during the (i) start mode and the (ii) run mode.
The second check valve may be open during the (iii) actuation mode.
A third check valve may be provided downstream of both the primary stage and the regenerative stage.
The third check valve may be open during the (i) start mode.
Fluid from the regenerative stage may proceed through the regenerative stage control valve and the third check valve in the (i) start mode.
The fuel pump system may include a control valve, a regenerative stage control valve, and a pressure regulator valve, where the control valve may be in communication with the primary stage for controlling operation thereof, the control valve may be in communication with the pressure regulator valve to selectively control fluid flow to the regenerative stage, the regenerative stage control valve may selectively control fluid flow from the regenerative stage for the (i) start mode, and the regenerative stage control valve may be in fluid communication with the outlet of the primary stage such that the regenerative stage control valve may selectively close in response to a preselected pressure at the primary stage outlet.
A method of supplying fuel from an associated fluid source to an associated downstream use(s) including for engine (i) start mode, (ii) run mode, and (iii) actuation mode is disclosed herein.
The method in a preferred arrangement selectively supplies pressurized flow for the (ii) run mode with a pump including a primary stage having an inlet and an outlet that is configured to selectively supply pressurized flow for the (ii) run mode. The method may further include selectively providing pressurized fluid for the (i) start mode and the (iii) actuation mode with a regenerative stage commonly driven with the primary stage.
An improved regenerative pump start mode and actuation stage for a high-speed centrifugal pump is advantageously provided.
Another benefit resides in simplifying the arrangement to direct pressurized flow from the high-speed centrifugal pump.
Another advantage resides in reducing sizes of various system components.
Still another advantage relates to providing a single pump for start-up, run, and actuation modes of the pump system.
Benefits and advantages of the present disclosure will become more apparent from reading and understanding the following detailed description.
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of one or more embodiments of the present disclosure as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the various embodiments described herein can be made without departing from the scope and spirit of the present disclosure. Various exemplary embodiments of the present disclosure are not limited to the specific details of different embodiments and should be construed as including all changes and/or equivalents or substitutes included in the ideas and technological scope of the appended claims. In describing the drawings, where possible similar reference numerals are used for similar elements.
The terms “include” or “may include” used in the present disclosure indicate the presence of disclosed corresponding functions, operations, elements, and the like, and do not limit additional one or more functions, operations, elements, and the like. In addition, it should be understood that the terms “include”, “including”, “have” or “having” used in the present disclosure are to indicate the presence of components, features, numbers, steps, operations, elements, parts, or a combination thereof described in the specification, and do not preclude the presence or addition of one or more other features, numbers, steps, operations, elements, parts, or a combination thereof.
The terms “or” or “at least one of A or/and B” used in the present disclosure include any and all combinations of words enumerated with them. For example, “A or B” or “at least one of A or/and B” mean including A, including B, or including both A and B.
Although the terms such as “first” and “second” used in the present disclosure may modify various elements of the different exemplary embodiments, these terms do not limit the corresponding elements. For example, these terms do not limit an order and/or importance of the corresponding elements, nor do these terms preclude additional elements (e.g., second, third, etc.) The terms may be used to distinguish one element from another element. For example, a first mechanical device and a second mechanical device all indicate mechanical devices and may indicate different types of mechanical devices or the same type of mechanical device. For example, a first element may be named a second element without departing from the scope of the various exemplary embodiments of the present disclosure, and similarly, a second element may be named a first element.
It will be understood that, when an element is mentioned as being “connected” or “coupled” to another element, the element may be directly connected or coupled to another element, and there may be an intervening element between the element and another element. To the contrary, it will be understood that, when an element is mentioned as being “directly connected” or “directly coupled” to another element, there is no intervening element between the element and another element.
The terms used in the various exemplary embodiments of the present disclosure are for the purpose of describing specific exemplary embodiments only and are not intended to limit various exemplary embodiments of the present disclosure. As used herein, the singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise.
All of the terms used herein including technical or scientific terms have the same meanings as those generally understood by an ordinary skilled person in the related art unless they are defined otherwise. The terms defined in a generally used dictionary should be interpreted as having the same meanings as the contextual meanings of the relevant technology and should not be interpreted as having inconsistent or exaggerated meanings unless they are clearly defined in the various exemplary embodiments.
A regenerative stage 130 of the pump 110 is commonly driven by the shaft 118. The regenerative stage 130 preferably includes a rotary member or impeller 132 operatively driven by the shaft 118. The rotary member 132 has vanes 134 preferably located adjacent the outer perimeter or periphery of the rotary member, and the vanes are preferably located on both of opposite, first and second faces 136, 138 of the rotary member. Suitable dynamic seals 140 and thrust and journal bearings 142 are provided to seal and support rotational movement of these pump components relative to a pump housing (not shown).
Downstream of the primary stage/centrifugal pump 116 is a first check valve 150. The first check valve 150 is biased toward a closed position by a biasing member such as spring 152. Until the fluid pressure at the pump outlet 120 is sufficient to overcome the biasing force, the first check valve 150 remains closed and therefore pressurized fuel to the main pump discharge 102 must be provided in another manner. Specifically, in the start mode as illustrated in
The electronic control valve 180 provides a suitable signal (e.g., an electrical signal 182) to the pressure regulator valve 154 during the start mode to assure that the pressure regulator valve 154 moves toward the open position shown in
Additionally, a second check valve 200 includes a biasing member or biasing spring 202 that normally closes the second check valve and prevents flow from the regenerative stage 130 from passing through the second check valve to the actuator pump discharge 104.
A third check valve 210 is configured to allow flow therethrough toward the actuator pump discharge 104 during the start mode (
Still another feature is the inclusion of an ejector 220 in the fuel pump system 100. A portion of the pressurized flow exiting from the regenerative stage 130 during start-up proceeds through branch line 222 to serve as a motive flow source to the ejector 220. This flow through branch line 222 proceeds through the ejector 220 and thereby draws pressurized fluid from branch passage 224 so as to exit the ejector 220 and be returned to the pump inlet 114 of the primary stage 116 via passage 226.
A portion of the flow to the main pump discharge 102 in the run mode (
As is also evident in
As is evident in
If during the run mode, there is a need for pressure to serve a downstream actuator (not shown) in fluid communication with the actuator pump discharge 104, a signal 182 is provided from the electronic control valve 180 and moves the pressure regulator valve 154 to an open position (
This written description uses examples to describe the disclosure, including the best mode, and also to enable any person skilled in the art to make and use the disclosure. Other examples that occur to those skilled in the art are intended to be within the scope of the invention if they have structural elements that do not differ from the same concept or that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the same concept or from the literal language of the claims. Moreover, this disclosure is intended to seek protection for a combination of components and/or steps and a combination of claims as originally presented for examination, as well as seek potential protection for other combinations of components and/or steps and combinations of claims during prosecution.
Although specific advantages have been enumerated above, various embodiments may include some, none, or all of the enumerated advantages. Although exemplary embodiments are illustrated in the figures and description herein, the principles of the present disclosure may be implemented using any number of techniques, whether currently known or not. Moreover, the operations of the systems and apparatuses disclosed herein may be performed by more, fewer, or other components, and the methods described herein may include more, fewer, or other steps. Additionally, steps may be performed in any suitable order.
To aid the Patent Office and any readers of this application and any resulting patent in interpreting the claims appended hereto, applicants do not intend any of the appended claims or claim elements to invoke 35 USC 112 (f) unless the words “means for” or “step for” are explicitly used in the particular claim.
| Number | Date | Country | |
|---|---|---|---|
| 62984913 | Mar 2020 | US |
