Patent ID: 12198839

DETAILED DESCRIPTION

A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.

Referring toFIG.1, illustrated is an embodiment of a sensor, in this embodiment a pitot tube10. The pitot tube10includes a cylindrical body portion12and a tip portion14extending along a tube axis16from the body portion12toward a tube inlet18. In the embodiment ofFIG.1, the tip portion14includes an inlet opening20having an inlet diameter22smaller than a body diameter24of the body portion12. The tip portion14, between the body portion12and the inlet opening20, tapers in diameter along a concave curve26. In some embodiments, the concave curve26does not extend entirely to the inlet opening20as the inlet diameter22extends axially from the inlet opening20to the concave curve26. It shall be understood that the curve26may be straight or a profile that is aerodynamically suitable in one embodiment.

As shown, the tip portion14has a tip length L. The length of the tip may be limited by an ability of a heating element or coils disposed inside the tip to provide heat to it. That is, if the tip is too long, the heater may not be able to heat a distal end thereof such that ice does not form or otherwise accumulate in or on the tip14.

Referring now toFIG.2, the pitot tube10includes an outer tube28and a tube sleeve30disposed inside of the outer tube28. The tube sleeve30extends along an interior of the pitot tube10to a tube end32, defining a tube passage34from a tip portion36of the pitot tube10to the tube end32. A heater coil38is disposed radially between the tube sleeve30and the outer tube28. The pitot tube10further includes one or more water dams40extending inwardly from the tube sleeve30into the tube passage34and one or more drain openings42extending from the tube passage34, through the tube sleeve30and the outer tube28to allow for egress of water from the pitot tube10.

The structure and a method of forming the pitot tube10will be further described below with reference to the flow diagram ofFIG.3and toFIGS.4-13. At block300ofFIG.3, the tube sleeve30is formed, in some embodiments by additive manufacturing, or by other suitable methods. The tube sleeve30is formed from a metallic material, such as a Nickel alloy, or other suitable metallic material.

As illustrated inFIGS.4and5, the tube sleeve30includes a sleeve outer surface44and a sleeve inner surface46. The sleeve inner surface46defines the tube passage34and the one or more water dams40extend from the sleeve inner surface46into the tube passage34. The tube sleeve30includes a sleeve wall48at a first sleeve end50that closes the tube passage34at the first sleeve end50, and is open at a second sleeve end52opposite the first sleeve end50. The tube sleeve30further includes one or more sleeve grooves54formed in the sleeve outer surface44to receive the heater coil38. Additionally, protrusions56extend outwardly from the sleeve outer surface44corresponding to locations of the drain openings42in the completed pitot tube10.

In block302ofFIG.3, the heater coil38is wound onto the tube sleeve30by inserting the heater coil38into the sleeve grooves54, as shown inFIG.6. In block304ofFIG.3, and as shown inFIG.7, a layer of braze paste58is applied to the sleeve outer surface44, covering the heater coil38, leaving the protrusions56, however, uncovered by the braze paste58.

In block306and as shown inFIG.8, the outer tube28is formed, having a through opening60extending from a first outer tube end62nearest the tip portion36to a second outer tube end64. The outer tube28further includes pre-drilled openings66extending through the outer tube28. The pre-drilled openings66are located at the drain opening42locations in the pitot tube10, but are oversized, compared to the finished drain openings42.

In block308, and as shown inFIG.9, the tube sleeve30is inserted into the outer tube28, and the protrusions46are aligned with the pre-drilled openings66. The tube sleeve30is inserted such that the sleeve wall48is located closest to the tip portion36, thereby defining a tip cavity68between the sleeve wall48and the tip portion36. At step310, the tube sleeve30/outer tube28assembly is brazed in, for example, a vacuum furnace. At step312, and referring toFIGS.10and11, the predrilled openings66and the tip cavity68are filled by, for example, a laser metal deposition process, and at step314a selected pitot tube tip profile70is formed in the filled tip cavity68by as illustrated inFIG.12by, for example, machining operations, and the drain openings42are drilled through the filled pre-drilled openings66and through the protrusions46as illustrated inFIG.13. At block316, the pitot tube10is then brazed or otherwise secured to a pitot tube strut (not shown).

The pitot tube10configuration disclosed herein allows for flexibility in material choices and manufacturing method of the separate outer tube28and tube sleeve30to enhance performance of the pitot tube10. Separate fabrication of the outer tube28and the tube sleeve30simplifies manufacturing of the pitot tube10, thereby reducing pitot tube10cost. Further, the configuration encloses the heater coil38, thereby protecting the heater coil38from damage or corrosion due to moisture exposure in the tube passage34. Adding the grooves to the tube sleeve30aids in winding of the heater coil38, improving the accuracy and repeatability thereof, and improves pitot tube10performance with consistent heater coil38application.

The term “about” is intended to include the degree of error associated with measurement of the particular quantity based upon the equipment available at the time of filing the application.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, element components, and/or groups thereof.

While the present disclosure has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from the essential scope thereof. Therefore, it is intended that the present disclosure not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this present disclosure, but that the present disclosure will include all embodiments falling within the scope of the claims.