US3723722A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helicopter lighting
Assignee: Smith and Nephew Inc
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Filing: 1970-09-14
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Granted: 1973-03-27
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Expires: 1990-09-14
Abstract
Abstract Relatively rotatable elements coupled for light transmission by fiber optic devices analogous to electrical commutators. A rotary wing aircraft embodiment employing fiber optics in the rotor blade for navigational lights has a flexible light pipe extension from the blade with an end fixed to move with the driving assembly in a set circular path, to sweep by and pick up light from a light source on the body. Other portions of the extension flex to follow cyclic pivoting of the blade relative to its driving assembly. Fibers in the blade are arranged to bend with the blade during operation by use of a flexible light pipe within which the fibers adjust relative to one another during blade bending. Heat-curing of plastic about a heat resistant flexible light pipe and bonding the fibers directly into the blade matrix as bendable strength element using a thin, wide and long ribbon of optical fibers are shown. Light sources on the body of the aircraft are shown as fiber light pipes with ends fixed to be swept by the pickup pipes. Four source light pipes provide light in accordance with navigational rules, a rotor blade receiving alternately white, green, white, red light as it rotates through various sectors. A Maxwellian lens at the end of a source light pipe defines an extended lighted arc along the pickup path, to provide extended duration of light transmission in each sector, the lens also enabling variation in the physical position of the blade assembly as occurs in the field.
Inventors
- 👤 Iderstine T Van
- 👤 L Bonnell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:49
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/0001; G02B6/0005; G02B6/0008; B; B64; B64C; B64C27/00; B64D; B64D47/00; B64D47/02; B64D47/06
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
186 words
In a rotor blade for a rotary wing aircraft, said blade including a set of optic fibers extending along the length of said blade for conducting light from an inboard end to an outboard end to provide navigational light, the improvement wherein said fibers are secured against lengthwise movement along said blade and are held in a manner permitting their bending to accommodate vertical bending of said blade during operation, and a flexible light pipe extension extends from an inboard portion of said blade and in light supplying relation to said optic fibers, said light pipe extension comprising light conducting fiber portions disposed within a flexible casing portion, and being mounted to rotate with said blade about the blade drive axis and adapted to flex with repeated cyclic pivoting of said blade about the latter''s longitudinal axis, said flexible light pipe extension having an end portion adapted to be held in a predetermined position relative to the rotating drive mechanism of the aircraft for describing a predetermined circular path to sweep by and pick up light from a light source on the body of said aircraft.
Claim 2
Dependent Claim
186 words
In a rotor blade for a rotary wing aircraft, said blade including a set of optic fibers extending along the length of said blade for conducting light from an inboard end to an outboard end to provide navigational light, the improvement wherein said fibers are secured against lengthwise movement along said blade and are held in a manner permitting their bending to accommodate vertical bending of said blade during operation, and a flexible light pipe extension extends from an inboard portion of said blade and in light supplying relation to said optic fibers, said light pipe extension comprising light conducting fiber portions disposed within a flexible casing portion, and being mounted to rotate with said blade about the blade drive axis and adapted to flex with repeated cyclic pivoting of said blade about the latter''s longitudinal axis, said flexible light pipe extension having an end portion adapted to be held in a predetermined position relative to the rotating drive mechanism of the aircraft for describing a predetermined circular path to sweep by and pick up light from a light source on the body of said aircraft.
Claim 3
Dependent Claim
76 words
The rotor blade of claim 1 wherein said fibers extending along the length of said blade comprise a flexible bundle housed in a flexible casing, said casing being disposed within said blade and secured against movement relative thereto, the internal cross-sectional area of said casing exceeding the aggregate cross-sectional area of said fibers of said bundle, thereby providing room for said fibers to adjust themselves relative to one another during bending of said blade during operation.
Claim 4
Dependent Claim
35 words
The rotor blade of claim 2 wherein said light pipe extension extending from the inboard portion of said blade is defined by an integral extension of said fibers and casing that are within said blade.
Claim 5
Dependent Claim
46 words
The rotor blade of claim 2 wherein said optic fibers are glass fibers joined together at their outer ends into a light transmitting end surface by heat-resistant bonding material, said casing comprises a heat-resistant housing, and said blade comprises heat-cured structure permanently secured about said casing.
Claim 6
Dependent Claim
23 words
The rotor blade of claim 1 wherein said optic fibers are embedded directly in a structural matrix defining a portion of said blade.
Claim 7
Dependent Claim
25 words
The rotor blade of claim 5 wherein said optic fibers are glass and are secured in a manner to contribute structural strength to said blade.
Claim 8
Dependent Claim
34 words
The rotor blade of claim 5 wherein outboard portions of said fibers protrude beyond said matrix into a housing, and end portions of said fibers are bonded together to define a light transmitting face.
Claim 9
Dependent Claim
26 words
The rotor blade of claim 5 wherein inboard portions of said fibers protrude beyond said matrix, forming the optic fiber portions of said light pipe extension.
Claim 10
Dependent Claim
74 words
The rotor blade of claim 1 wherein said fibers are secured to each other in the form of a substantially flat ribbon, said ribbon being bonded to other structural portions of said blade extending in the direction of the length of said blade, with its widthwise direction extending in the direction between the leading and trailing edges of said blade and the direction of its thickness aligned with the direction of operational blade bend.
Claim 11
Dependent Claim
18 words
The rotor blade of claim 9 wherein a plurality of said ribbons comprise structural members of said blade.
Claim 12
Dependent Claim
100 words
An aircraft including the rotor blade of claim 1 mounted on a rotating driving mechanism defining said drive axis, and a control assembly for cyclic pivoting of said blade to alter its angle of attack, the end of said light pipe extension being secured to the rotary portion of said driving mechanism and adapted to describe a predetermined circular path relative to the body of the aircraft, and at least one light source mounted on the body of the aircraft, said light source being disposed to focus light on a portion of said circular path of said light pipe end.
Claim 13
Dependent Claim
35 words
The aircraft of claim 11 wherein said light source includes a lens providing a depth of focus which permits variation in tolerance of the relative positioning of said blade and said body of said aircraft.
Claim 14
Dependent Claim
45 words
The aircraft of claim 11 wherein said light source is defined by at least one fiber optic light pipe mounted on said body of said aircraft, said fiber optic light pipe having a light-output end surface positioned to transmit a point on said circular path.
Claim 15
Dependent Claim
237 words
In combination a rotor blade for a rotary wing aircraft having disposed in the body thereof a lamp, said blade having disposed thereon an element arranged to transmit light and means for supplying light from the inboard end of said blade to said element, structure defining two assemblies, one movable relative to the other, and including first and second fiberoptic light pipes associated respectively with each assembly, the input end surface of said first light pipe being arranged to receive light from said lamp, the output end surface of said first light pipe defining an object plane, the input end surface of said second light pipe defining an image plane and the output end surface of said second light pipe being arranged to deliver the transmitted light to said element, the end surfaces defining said object plane and said image plane being spaced apart and relatively movable between at least one position in which they are disposed in light transmitting alignment and at least one position in which they are out of light transmitting alignment, and focusing structure disposed between said image and object planes and comprising a lens assembly including a lens, said lens assembly being spaced apart from one of said end surfaces defining one of said planes, and said lens being arranged to effectively focus light between said object plane and said image plane when said planes are in said light transmitting alignment. Pg,25
Claim 16
Dependent Claim
237 words
In combination a rotor blade for a rotary wing aircraft having disposed in the body thereof a lamp, said blade having disposed thereon an element arranged to transmit light and means for supplying light from the inboard end of said blade to said element, structure defining two assemblies, one movable relative to the other, and including first and second fiberoptic light pipes associated respectively with each assembly, the input end surface of said first light pipe being arranged to receive light from said lamp, the output end surface of said first light pipe defining an object plane, the input end surface of said second light pipe defining an image plane and the output end surface of said second light pipe being arranged to deliver the transmitted light to said element, the end surfaces defining said object plane and said image plane being spaced apart and relatively movable between at least one position in which they are disposed in light transmitting alignment and at least one position in which they are out of light transmitting alignment, and focusing structure disposed between said image and object planes and comprising a lens assembly including a lens, said lens assembly being spaced apart from one of said end surfaces defining one of said planes, and said lens being arranged to effectively focus light between said object plane and said image plane when said planes are in said light transmitting alignment. Pg,25
Claim 17
Dependent Claim
79 words
The combination of claim 14 wherein said lens assembly is arranged to focus, in the direction of said image plane, light from said object plane over a region having a minimum dimension, in the direction of relative movement, which is substantially greater than the corresponding dimension of said input end surface of said second light pipe, said light transmitting alignment occurring when any portion of said region and said input end surface of said second light pipe are aligned.
Claim 18
Dependent Claim
90 words
The combination of claim 15 wherein one of said two relatively movable members is a rotary member arranged to rotate relative to the other of said relatively movable members and the said output end surface of said second light pipe, when light is transmitted thereto, is arranged to provide a navigational light, the ratio of the magnitude of said minimum dimension of said region to the perimeter of said rotatably movable member thereby determining the portion of each revolution of said rotary member during which said navigational light is energized.
Claim 19
Dependent Claim
114 words
A navigational lighting system for rotary wing aircraft, said lighting system comprising an optic assembly including optic fibers extending along the length of each blade for conducting light from the inboard end to the outboard end thereof, an inner portion of the assembly for each blade adapted to be held in a respective predetermined position relative to the central rotating mechanism of the aircraft, spaced from the axis thereof for describing a predetermined circular path, and a light source mounted on the body of the aircraft illuminating a sector of said circular path, for directing light into said fiber optic assembly, thence to the outer end of said assembly to provide a navigational light.
Claim 20
Dependent Claim
114 words
A navigational lighting system for rotary wing aircraft, said lighting system comprising an optic assembly including optic fibers extending along the length of each blade for conducting light from the inboard end to the outboard end thereof, an inner portion of the assembly for each blade adapted to be held in a respective predetermined position relative to the central rotating mechanism of the aircraft, spaced from the axis thereof for describing a predetermined circular path, and a light source mounted on the body of the aircraft illuminating a sector of said circular path, for directing light into said fiber optic assembly, thence to the outer end of said assembly to provide a navigational light.
Claim 21
Dependent Claim
31 words
The navigational lighting system of claim 17 wherein there are a plurality of light sources mounted on the body of said aircraft, each illuminating a different sector of said circular path.
Claim 22
Dependent Claim
34 words
The navigational lighting system of claim 18 wherein there are two light sources, one red, the other green, associated respectively with the left and right sides of the circular path relative to the aircraft.
Claim 23
Dependent Claim
41 words
The navigational lighting system of claim 18 wherein said plurality of light sources comprise a plurality of fiber light pipes, the output ends thereof associated with different sectors of said circular path, the input ends thereof associated with a common lamp.
Claim 24
Dependent Claim
18 words
The navigational lighting system of claim 17 wherein the circular path for all of said blades are coincident.
Claim 25
Dependent Claim
53 words
The lighting system of claim 17 in which said light source comprises the combination of a lamp, a fiber optic light pipe conducting light from the lamp to an output end surface, and a lens assembly arranged to focus the object of said end surface upon an image plane coincident with said path.
Claim 26
Dependent Claim
61 words
The combination of claim 22 wherein said lens assembly is arranged to provide a light image having a depth of field sufficient to permit variations in tolerance of the relative positioning of the output end surface of said light pipe and the inboard end of said optic assembly without loss of effective transmission of light from said source to said assembly.
Claim 27
Dependent Claim
19 words
The combination of claim 23 wherein said lens assembly has two lenses and is a Maxwellian field lens assembly.
Claim 28
Dependent Claim
96 words
The combination of claim 22 wherein the spacing between said output end surface of said light pipe and said inboard end of said optic assembly is adapted to be one of a plurality of possible spacings and is determined by the installation of said combination and said lens assembly is arranged to be adjusted to conform to said actual spacing and thereby to effectively transmit light from said output end surface of said first light pipe to said inboard end of said optic assembly when said actual spacing is any of said plurality of possible spacings.
Claim 29
Dependent Claim
71 words
The combination of claim 22 wherein said lens assembly is arranged to focus, in the direction of said image plane, lighT from said object over a region having a dimension, in the direction of circular movement of said blade which is substantially greater than the corresponding dimension of said inboard end of said optic assembly, light transmitting alignment occurring when any portion of said region and said inboard end are aligned.
Claim 30
Dependent Claim
47 words
The combination of claim 26 wherein the ratio of the magnitude of said dimension of said region to the perimeter of said circular path, determining the portion of each revolution of said rotary member during which said light is transmitted is established according to aircraft navigational rules.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |