The present disclosure relates to a method and apparatus for hard machining orifices in various fuel system and engine components and, more particularly, to precision hard machining of orifices and small internal holes for engine, fuel systems, dosers and drivetrain components.
Machining orifices and small internal holes can include utilizing special machine tools, fixtures, cutting tools and manufacturing processes in order to make a precise feature. Current methods and apparatuses use abrasive flow machining to create various orifices in fuel system and engine components.
Disclosed herein are methods for hard machining at least one orifice into a heat-treated fuel system component. Such a method can include the at least one orifice including a first orifice. The method can include mounting the heat-treated fuel system component into a holding fixture. The method can include determining a desired orifice size of the at least one orifice based on a desired flow rate. The method can include hard machining the first orifice into the heat-treated fuel system component. The hard machining the first orifice can include forming (e.g., machining) a first portion of the first orifice. The hard machining the first orifice can further include forming, at an end of the first portion, a second portion of the first orifice. A diameter of the second portion can be smaller than a diameter of the first portion. The hard machining the first orifice can include forming a corner between the first portion and the second portion. The corner can have an edge condition. The edge condition can have a dimension of 50 microns or less.
In examples, the hard machining the first orifice can include precision sizing at least one of the first portion and the second portion. In examples, forming a corner can include forming the edge condition as a chamfer (e.g., a linear transitional edge between end 18a and second portion 20). In examples, forming a corner can include forming the edge condition as a round (e.g., a convex radiused transition between end 18a and second portion 20).
In examples, the method can include performing the hard machining the at least one orifice by a machine tool. In this regard, the holding fixture can be a stationary holding fixture of the machine tool. In examples, the determining the desired orifice size can include selecting the desired orifice size based on a graph correlating a set of orifice sizes to a set of flow rates.
In examples, the method can include the at least one orifice further including a second orifice. The second orifice can include a cross hole. In this regard, the method can further include hard machining the second orifice into the heat-treated fuel system component. The second orifice can have a different configuration than the first orifice. The hard machining the second orifice can include forming a flat bottom pilot. The hard machining the second orifice can further include end machining the cross hole into the flat bottom pilot.
In examples, the method can include the forming the first portion further including hard machining a face into the heat-treated fuel system component. The forming the first portion can further include hard machining a pilot hole into the heat-treated fuel system component.
In examples, the method can optionally include the heat-treated fuel system component being an injector needle.
In another embodiment of the present disclosure, a heat-treated fuel system component can include at least one orifice. The at least one orifice can be hard machined into a body of the heat-treated fuel system component based on a desired flow rate of the at least one orifice. The at least one orifice can include a first orifice. The first orifice can include a first portion and a second portion. The second portion can be hard machined at an end of the first portion. A diameter of the second portion can be smaller than a diameter of the first portion. A corner between the first portion and the second portion can have an edge condition. The edge condition can have a dimension of 50 to 100 microns. In other aspects, the edge condition can be 50 microns or less.
In examples, the edge condition can include a chamfer. In examples, the edge condition can include a round.
In examples, the at least one orifice can further include a second orifice. The second orifice can include at least one of a flat bottom pilot and a cross hole.
In examples, the first portion can include a face hard machined into the heat-treated fuel system component. A pilot hole can be hard machined into the heat-treated fuel system component.
In examples, the heat-treated fuel system component can optionally include an injector needle.
A machining system can include a component fixture configured to mount a heat-treated fuel system component. The machining system can further include a machine tool. The machine tool can be configured to form a first portion of a first orifice of at least one orifice in the heat-treated fuel system component. The machine tool can further be configured to form, at an end of the first portion, a second portion of the first orifice. A diameter of the second portion can be smaller than a diameter of the first portion. The machine tool can further be configured to form a corner between the first portion and the second portion. The corner can have an edge condition having a dimension of 50 microns or less.
In examples, the system can further comprise a forming component configured to receive a drill bit. The forming component can further be configured to translate up and down relative to the component fixture to drill the at least one orifice into the heat-treated fuel system component held by the component fixture.
In examples, the component fixture can be formed of a rigid material configured to support a load applied to the fixture.
Advantages and features of the embodiments of this disclosure will become more apparent from the following detailed description of exemplary embodiments when viewed in conjunction with the accompanying drawings.
For the purposes of promoting an understanding of the principles of the present disclosure, reference is now made to the embodiments illustrated in the drawings, which are described below. The exemplary embodiments disclosed herein are not intended to be exhaustive or to limit the disclosure to the precise form disclosed in the following detailed description. Rather, these exemplary embodiments were chosen and described so that others skilled in the art may utilize their teachings. It is not beyond the scope of this disclosure to have a number (e.g., all) the features in a given embodiment to be used across all embodiments.
Aspects of the disclosure provide several advantages over existing methods. For instance, such methods can reduce the capital investment and cycle time for machining of orifices and small internal holes for engine, fuel systems, dosers and drivetrain components and reduces proliferation across applications. Traditional methods include end milling a component where forming of the hole is performed following a helical path (e.g., movement along the x, y, and z axes), which introduces air that will affect flow properties of the machining. Artisans have turned to abrasive flow machining (AFM) for this reason, but AFM lacks the precision required for certain forming. With the disclosed method, components can be hard drilled using drill edges that account for heat profile of the forming, material type, and hardness and performed without forming in a helical pattern, resulting in a simple directional forming pattern. Thus, embodiments of the present disclosure can facilitate production of fluid components, such as fuel system components, having relatively consistent, accurate flow rates. Component tuning is even more possible without driving changes to the manufacturing process. Employing principles of the present disclosure can optimize engine-related components while keeping cost to develop very low. Hard machining capabilities can save money across the global manufacturing organization and can be applied in many different applications.
Devices, systems, and methods of the present disclosure can be employed when it is desirable to have precision-made holes that are used to control, direct, and transfer fluid, such as air. Such fluid can have a flow that is sensitive to certain parameters like size, surface finish, shape, sharp edges and high flow rates. Certain existing methods like electrical discharge machining (EDM) and Laser can include high investment costs and development time. Other existing methods like electro chemical machining (ECM), electro chemical deburring (ECD), soft machining can exhibit relatively low accuracy. Yet other existing methods (such as abrasive flow machining (AFM) and honing) can be expensive, cumbersome, and/or require additional processes.
Various aspects of methods disclosed herein can be seen in
Referring to
Machine tools can include milling machines, lathes, drill presses, and the like. To determine the tool bit size for orifice 14, 16, graph 150 (
A method for hard machining, as in step 108, at least one orifice 14, 16 into a heat-treated fuel system component 10 includes mounting the heat-treated fuel system component 10 into a holding fixture (e.g., 500,
Hard machining the first orifice can further includes precision sizing at least one of the first portion 18 and the second portion 20. Forming a corner 15 can include forming the edge condition as a chamfer or as a round. Determining the desired orifice size can include selecting the desired orifice size based on a graph, such as the graph shown in
The example method of step 108 can further include performing the hard machining the at least one orifice 14, 16 by a machine tool 400, wherein the holding fixture is a stationary holding fixture 500 (shown in
The example method of step 108 can further include the at least one orifice 14, 16 including a second orifice 16 comprising a cross hole (see, e.g.,
In examples, the method of step 108 can include the forming the first portion 18 further including hard machining a face into the heat-treated fuel system component (see, e.g.,
In examples, the method of step 108 can optionally include mounting the heat-treated fuel system component into a holding fixture including mounting an injector needle blank 10 as the heat-treated fuel system component.
In examples, the method of step 108 can optionally include a heat-treated fuel system component, such as an injector needle 800, formed using the method 100, and more specifically step 108, described above.
Experimental results have substantiated aspects of the present disclosure and are shown in
Aspects of another embodiment employing principles of the present disclosure are seen in
As indicated in
With reference to
Referring to
It is well understood that methods that include one or more steps, the order listed is not a limitation of the claim unless there are explicit or implicit statements to the contrary in the specification or claim itself. It is also well settled that the illustrated methods are just some examples of many examples disclosed, and certain steps can be added or omitted without departing from the scope of this disclosure. Such steps can include incorporating devices, systems, or methods or components thereof as well as what is well understood, routine, and conventional in the art.
The connecting lines shown in the various figures contained herein are intended to represent exemplary functional relationships and/or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections can be present in a practical system. However, the benefits, advantages, solutions to problems, and any elements that can cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as critical, required, or essential features or elements. The scope is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” Moreover, where a phrase similar to “at least one of A, B, or C” is used in the claims, it is intended that the phrase be interpreted to mean that A alone can be present in an embodiment, B alone can be present in an embodiment, C alone can be present in an embodiment, or that any combination of the elements A, B or C can be present in a single embodiment; for example, A and B, A and C, B and C, or A and B and C.
In the detailed description herein, references to “one embodiment,” “an embodiment,” “an example embodiment,” etc., indicate that the embodiment described can include a particular feature, structure, or characteristic, but every embodiment can not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art with the benefit of the present disclosure to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described. After reading the description, it will be apparent to one skilled in the relevant art(s) how to implement the disclosure in alternative embodiments.
Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. 112(f), unless the element is expressly recited using the phrase “means for.” As used herein, the terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.
While various embodiments of the disclosure have been shown and described, it is understood that these embodiments are not limited thereto. The embodiments may be changed, modified and further applied by those skilled in the art. Therefore, these embodiments are not limited to the detail shown and described previously, but also include all such changes and modifications.
Number | Date | Country | |
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63209607 | Jun 2021 | US |
Number | Date | Country | |
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Parent | PCT/US22/33086 | Jun 2022 | US |
Child | 18519527 | US |