Metallic hot wire anemometer

Claim 2

A hot wire anemometer for measuring air flow along a path comprising a metallic body, said body defining a narrow edge face and tapering surfaces diverging rearward from said edge face, said body defining first and second cylindric holes terminating at their outer ends at spaced apart locations in said edge face and at their other ends at a portion of the body remote from said edge face, first and second electrical conductor rods disposed in respective said holes and having distal ends accessible from said edge face, means circumscribing said conductor rods for electrically insulating said conductor rods from one another, a probe wire secured to the distal ends of said conductor rods, and means for securing said probe wire throughout its length to said edge face, said securing means partially circumscribing said wire, said securing means comprising a ceramic adhesive whereby said probe wire may be operated at a temperature at least as high as 1,300° F.

Claim 3

An anemometer according to claim 1 wherein said insulating means comprises an oxide coating formed in situ in said holes.

Claim 4

An anemometer according to claim 1 wherein said body and said conductor rods are formed of high purity nickel, and wherein said insulating means includes an oxide of nickel formed in situ.

Claim 5

An anemometer according to claim 1 wherein said ceramic adhesive is confined to the portion of said probe wire confronting said edge face so that the opposite portion of said probe wire is exposed to air flowing along said path.

Claim 6

An anemometer according to claim 4 wherein said body defines a V groove in said edge face in parallelism with said probe wire and wherein said ceramic adhesive resides within said V groove.

Claim 7

An anemometer according to claim 5 wherein said V groove has a width no greater than about one-half the width of said edge face.

Claim 8

An anemometer according to claim 1 including said remote body portion defining a bore communicating with said holes, said conductor rods extending into said bore, and means in said bore for sealing said bore and supporting said conductor rods.

Claim 9

An anemometer according to claim 7 wherein said first hole extends obliquely of said bore so that there is a radial offset between opposite ends of said first hole, said bore having a diameter at least as large as said radial offset to permit installation of said first conductor rod in said first hole without distorting said conductor rod.

Claim 10

A hot wire anemometer for measuring air flow along a path comprising a metallic body having a central axis and an outer cylindric surface concentric with said axis, said body having a forward end defining two edge faces diverging rearward from said central axis, said body defining streamlining surfaces diverging rearward from respective said edge faces, said edge faces each defining a V groove therein, each said V groove having an inner extremity adjacent said axis and an outer extremity adjacent said cylindric surface, said body defining in a region remote from said edge faces a bore substantially concentric of said axis, first and second cylindric holes extending parallel to said axis between said bore and inner extremities of respective said V grooves, third and fourth cylindric holes extending obliquely from said bore to the outer extremities of respective said V grooves, first, second, third and fourth conductor rods disposed in respective said holes, an oxide coating formed in situ in circumscribing relation to said rods for insulating said rods from said body and for fixing said rods within said body, first and second probe wires disposed in respective said V grooves and fixed to the ends of said conductors in said V grooves, a ceramic adhesive disposed in said V grooves for supporting said probe wires throughout their lengths, said ceramic adhesive being confined to the portion of said probe wires confronting said V grooves so that opposite portions of said probe wires are exposed to air flowing on said path, and means in said bore for sealing and supporting said conductor rods therein.

Claim 11

A hot wire anemometer for measuring air flow along a path comprising a metallic body having a central axis and an outer cylindric surface concentric with said axis, said body having a forward end defining two edge faces diverging rearward from said central axis, said body defining streamlining surfaces diverging rearward from respective said edge faces, said edge faces each defining a V groove therein, each said V groove having an inner extremity adjacent said axis and an outer extremity adjacent said cylindric surface, said body defining in a region remote from said edge faces a bore substantially concentric of said axis, first and second cylindric holes extending parallel to said axis between said bore and inner extremities of respective said V grooves, third and fourth cylindric holes extending obliquely from said bore to the outer extremities of respective said V grooves, first, second, third and fourth conductor rods disposed in respective said holes, an oxide coating formed in situ in circumscribing relation to said rods for insulating said rods from said body and for fixing said rods within said body, first and second probe wires disposed in respective said V grooves and fixed to the ends of said conductors in said V grooves, a ceramic adhesive disposed in said V grooves for supporting said probe wires throughout their lengths, said ceramic adhesive being confined to the portion of said probe wires confronting said V grooves so that opposite portions of said probe wires are exposed to air flowing on said path, and means in said bore for sealing and supporting said conductor rods therein.