Abstract: A structure (10) for reducing vibratory airloading in a rotor blade (12) with a leading edge (14) and a trailing edge (16) includes a cut-out portion (18) at the trailing edge. A substantially wedge shaped cross-section, inertially deflectable tab (20), also having a leading edge (22) and a trailing edge (24) is pivotally mounted in the cut-out portion. The trailing edge (24) of the tab (20) may move above and below the rotor blade (12). A torsion strap (26 or 64) applies force against the tab (20) when the trailing edge (24) of the tab (20) is above and below the rotor blade (12). A restraining member (92) is slidably movable along the torsion strap (64) to vary torsional biasing force supplied by the torsion bar (64) to the tab (20). A plurality of movable weights (82) positioned between plates (84) and (86) vary a center of gravity of the tab (20). Skin (74) of the tab (20) is formed from unidirectional graphite and fiberglass layers.

Abstract: Method of forming 4,4',4",4'"-tetraamino phthalocyanines by reducing 4,4',4",4'"-tetranitro phthalocyanines, polymerization of the metal tetraamino phthalocyanines with a tetracarboxylic dianhydride (preferably aromatic) or copolymerization with a tetracarboxylic dianhydride and a diamine (preferably also aromatic) to produce amic acids which are then dehydrocyclized to imides. Thermally and oxidatively stable polymers result which form tough, flexible films, etc.

Abstract: Cured polymers of bis- and tris-imides derived from tris(m-aminophenyl) phosphine oxides by reaction with maleic anhydride or its derivatives, and addition polymers of such imides, including a variant in which a mono-imide is condensed with a dianhydride and the product is treated with a further quantity of maleic anhydride prior to curing are disclosed and claimed. Such polymers are flame resistant. Also disclosed are an improved method of producing tris(m-aminophenyl) phosphine oxides from the nitro analogues by reduction with hydrazine hydrate using palladized charcoal or Raney nickel as the catalyst and fiber-reinforced cured resin composites.

Abstract: A method for preparing water-insoluble asymmetric reverse osmosis membranes from water-soluble polymers is disclosed. The method involves casting a polymer film, partially drying it and then contacting it with a transition metal polyvalent ion solution. Optionally, the product of the contacting is cross-linked such as by radiation or heat. The membrane products are disclosed as well.

Abstract: The invention relates to metal, primarily divalent metal such as divalent copper, cobalt and nickel, 4,4',4", 4'" phthalocyanine tetracarboxylic acids and to polymers prepared by heating the same, and to a method of preparing the tetracarboxylic acids.A method is provided for preparing the aforesaid tetracarboxylic acids in purer form than heretofore. Upon heating these acids decarboxylate and produce polymers.These polymers have diphenyl (conjugated) types of linkage; they are thermally and oxidatively stable and useful as sheet polymers for various purposes such as heat shielding.The monomeric tetracarboxylic acid is shown in FIG. 1, the polymer in FIG. 2 and thermal resistance in FIG. 3.The monomeric tetracarboxylic acids are prepared in purer form than heretofore, the resulting polymers are more stable thermally and oxidatively than metal phthalocyanine polymers and monomers heretofore made.

Abstract: Flame-resistant reinforced bodies are disclosed which are composed of reinforcing fibers, filaments or fabrics in a cured body of bis- and tris-imide resins derived from tris(m-aminophenyl) phosphine oxides by reaction with maleic anhydride or its derivatives, or of addition polymers of such imides, including a variant in which a mono-imide is condensed with a dianhydride and the product is treated with a further quantity of maleic anhydride.

Abstract: The invention generally relates to methods and devices for installing in a tubular shaft multiple strain gages, and more particularly to a method and a device for pneumatically forcing strain gages into seated engagement with the internal surfaces of a tubular shaft in an installation of multiple strain gages in a tubular shaft. The essence of the invention involves the novel concept of seating strain gages or other electronic devices in a template-like component, wrapping the template-like component about a pneumatically expansible body, inserting the component into a shaft and expanding the body pneumatically, a suitable adhesive having been applied to the surfaces.

Abstract: The object of the invention is to provide an improved laser altimeter for a flight simulator which will allow measurement of the height of the simulator probe above the terrain directly below the probe tip.A laser beam 22 is directed from the probe 13 at an angle .theta. to the horizontal to produce a beam spot 20 on the terrain. The angle .theta. that the laser beam 22 makes with the horizontal is varied so as to bring the beam spot into coincidence with a plumb line 18 coaxial with the longitudinal axis of the probe 13. A television altimeter camera 30 observes the beam spot and has a raster line aligned with the plumb line 18. Spot detector circuit 26 coupled to the output of the TV camera monitors the position of the beam spot relative to the plumb line 18. An error signal is produced by computer 28 driving, via a servo motor 23, the laser beam optics so as to cause the beam spot to come into coincidence with the plumb line 18.

Abstract: An automatic thermal switch to control heat flow includes a first thermally conductive plate 2, a second thermally conductive plate 25 and a thermally conductive switch saddle 1 pivotally mounted to the first plate 2. A flexible heat carrier 27 is connected between the switch saddle 1 and the second plate 25. A phase-change power unit 9, including a piston 13 coupled to the switch saddle 1, is in thermal contact with the first thermally conductive plate 2. A biasing element 21 biases the switch saddle 1 in a predetermined position with respect to the first plate 2. When the phase-change power unit 9 is actuated by an increase in heat transmitted through the first plate 2, the piston 13 extends and causes the switch saddle 1 to pivot thereby varying the thermal conduction between the first and second plates 2 and 25 through the switch saddle 1 and flexible heat carrier 27.

Abstract: This invention relates to a method of carbonizing polyacrylonitrile fibers (PAN fibers) by exposing the fibers at an elevated temperature to an oxidizing atmosphere, then exposing the oxidized fibers to an atmosphere of an inert gas such as nitrogen containing a carbonaceous material such as acetylene. The fibers are preferably treated with an organic compound, for example benzoic acid, before the exposure to an oxidizing atmosphere. The invention also relates to the resulting fibers. The treated fibers have enhanced tensile strength.

Abstract: A high temperature stable and solar radiation stable thermal control coating either useful as such, applied directly to a member to be protected, or applied as a coating on a re-usable surface insulation (RSI) has a base coat layer and an overlay glass layer. The base coat layer has a high emittance, and the overlay layer is formed from discrete, but sintered together glass particles to give the overlay layer a high scattering coefficient. The resulting two-layer space and thermal control coating has an absorptivity-to-emissivity ratio of less than or equal to 0.4 at room temperature, with an emittance of 0.8 at 1200.degree. F. It is capable of exposure to either solar radiation or temperatures as high as 2000.degree. F. without significant degradation. When used as a coating on a silica substrate to give an RSI structure, the coatings of this invention show significantly less reduction in emittance after long term convective heating and less residual strain than prior art coatings for RSI structures.

Abstract: An apparatus is described for moving a probe (12) that engages moving living tissue such as a heart or an artery that is penetrated by the probe, which moves the probe in synchronism with the tissue to maintain the probe at a constant location with respect to the tissue. The apparatus includes a servo positioner (18) which moves a servo member (20) to maintain a constant distance from a sensed object (30) while applying very little force to the sensed object, and a follower (26) having a stirrup (28) at one end resting on a surface of the living tissue and another end carrying a sensed object (30) adjacent to the servo member. A probe holder (34) has one end mounted on the servo member (20) and another end which holds the probe (12). The probe is held adjacent to the stirrup (28) of the follower assembly, so that movements of the tissue and therefore of the follower assembly (26) result in corresponding movement of the probe (12) to follow the surface of the tissue.

Abstract: A portable dual-laser-beam interferometer is described that nonintrusively measures skin friction by monitoring the thickness change of an oil film at two locations while said oil film is subjected to shear stress. An interferometer flat is utilized to develop the two beams. Light detectors sense the beam reflections from the oil film and the surface thereunder. The signals from the detectors are recorded so that the number of interference fringes produced over a given time span may be counted.

Abstract: A spark chamber frame 8 is manufactured using only inorganic materials. Spark chamber frame 8 includes a plurality of beams 10, 12, 14, and 16 formed from inorganic material, such as ceramic or glass, and are connected together at ends 9 with inorganic bonding material having substantially the same thermal expansion as the beam material. A plurality of wires 18 and 20 formed from an inorganic composition are positioned between opposed beams 10 and 14 and 12 and 16 so that wires 18 and 20 are uniformly spaced and form a grid. A plurality of hold-down straps 22, 23, 24, and 25 are formed of inorganic material such as ceramic or glass having substantially the same chemical and thermal properties as the beam material. Hold-down straps 22, 23, 24, and 25 overlie wires 18 and 20 extending over beams 10, 12, 14, and 16 and are bonded thereto with inorganic bonding material.

Abstract: A linear magnetic motor/generator (10) is disclosed which uses magnetic flux to provide mechanical motion or electrical energy. The linear magnetic motor/generator (10) includes an axially movable actuator mechanism (12). A permanent magnet mechanism (14) defines a first magnetic flux path (16) which passes through a first end portion (18) of actuator mechanism (12). Another permanent magnet mechanism (20) defines a second magnetic flux path (22) which passes through a second end portion (24) of actuator mechanism (12). A drive coil (26) defines a third magnetic flux path (28) passing through a third central portion (30) of actuator mechanism (12). Drive coil (26) selectively adds magnetic flux to and subtracts magnetic flux from magnetic flux flowing in the first and second magnetic flux paths (16) and (22), respectively, for supplying an axial force to the actuator mechanism (12).

Abstract: An aerial vehicle rotating in gyroscopic fashion about one of its axes having an optical system operative to scan an area below the vehicle in determined relation to vehicle rotation. A sensing device is provided to sense the physical condition of the area of scan and optical means are associated therewith to direct the physical intelligence received from the scan area to the sensing means. Means are provided to incrementally move the optical means through a series of steps to effect sequential line scan of the area being viewed keyed to the rotational rate of the vehicle.

Abstract: A laser measuring system for incremental assemblies such as wire-wrapped frame assemblies used in spark chambers and the like is disclosed. The system utilizes a laser (10), an interferometer (11) and a retroreflector (12) to precisely measure distance. A light source (17) and a photodetector (18) are located adjacent the incremental assembly and mounted on a movable carriage (13). The interferometer (11) is also mounted on the movable carriage (13), while the laser (10) and retroreflector (12) are positioned at either end of the carriage track. The carriage (13) is moved along one edge of the incremental assembly between the retroreflector (12) and the laser (10), and as the carriage (13) is moved, the light from the light source (17) to the photodetector (18) is interrupted. This produces a trigger command to a control unit (20) which in turn causes a distance measurement to be made.

Abstract: A cervix-to-rectum measuring device to be used in the treatment of cervical cancer which includes a handle and a probe pivotably connected to the handle for insertion in the rectum. The measuring device further includes means for coupling the handle to an intrauterine radiation applicator when the latter is positioned in the uterine cervix and the probe is inserted in the rectum to pivot the handle about the probe. A gear is provided which is adapted to pivot with the probe. A pinion pivotably connected to the handle meshes with the gear. A pointer fixed to the pinion is displaced in response to the pivoting of the handle about the probe, and this displacement can be read from a scale on the handle, providing an indication of the cervix-to-rectum distance.

Abstract: An automatic thermal switch to control heat flow includes a first thermally conductive plate, a second thermally conductive plate and a thermal transfer plate pivotally mounted between the first and second plates. A phase-change power unit, including a plunger connected to the transfer plate, is in thermal contact with the first thermally conductive plate. A biasing element, connected to the transfer plate, biases the transfer plate in a predetermined position with respect to the first and second plates. When the phase-change power unit is actuated by an increase in heat transmitted through the first plate, the plunger extends and pivots the transfer plate to vary the thermal conduction between the first and second plates through the transfer plate. The biasing element, transfer plate and piston can be arranged to provide either a normally closed or normally open thermally conductive path between the first and second plates.

Abstract: A method of making V-MOS field effect transistors is disclosed wherein a masking layer is first formed over a surface of a crystalline substrate. An aperture is then formed in the masking layer to expose the surface of the substrate. An anisotropic etchant is applied to the exposed surface so that a groove having a decreasing width within increasing depth is formed. However, the etch is not allowed to go to completion with the result that a partially formed V-shaped groove is formed. Ions are accelerated through the aperture for implantation in the crystalline substrate in the lower portion of the partially formed V-shaped groove. Thereafter, an anisotropic etchant is reapplied to the partially formed V-shaped groove, and the etch is allowed to go to completion.