Showing papers on "Bend radius published in 1999"

Fiber optic interconnection combination closure

Abstract: A fiber optic interconnection combination closure is provided for fashioning optical fiber connections in an enclosed chamber protected from environmental conditions and fiber stress. Fiber splices are fashioned in splice organizers within a closure base assembly. Fiber terminations are fashioned at termination adapters arrayed in a closure chassis. Bend limits for optical fiber are maintained as the fiber is directed on paths in the closure to/from splice organizers, termination adapters, and closure exit portals. Fiber is organized, strain relieved and collected by fiber clips, rings, retainers, and looms positioned such that directed fiber is maintain at a minimum bend radius on such fiber paths. Provided slack storage facilities allow fiber connections to be handled individually without disturbing other connections and/or fibers. Fibers are retained, organized and guided in a path on the closure exterior by attached wire brackets. In this manner, optical signal degradation and/or total loss is avoided by limiting the bending of routed optical fiber to radii in excess of a predetermined minimum bend radius.

Fiber optic evanescent field absorption sensor: Effect of fiber parameters and geometry of the probe

Abstract: A comparative experimental study of the fiber-optic evanescent field absorption sensor based on straight and U-shaped probes is presented. The effects of numerical aperture and the core radius of the fiber on the sensitivity of the sensor are experimentally investigated. Increase in the numerical aperture of the fiber increases the sensitivity of the sensor in the case of both the probes. The effect of core radius on the sensitivity depends on the bending radius of the probe. In the case of straight probe (i.e. infinite bending radius) the fiber with smaller core radius has high sensitivity while in the case of U-shaped probe with 0.17 cm bending radius, the fiber with larger core radius has high sensitivity. Thus, which fiber (with small or large core radius) has maximum sensitivity depends on the bending radius of the probe. For a given fiber, decrease in the bending radius increases the sensitivity of the U-shaped probe. An inverse power law relationship between the bending radius and the evanescent absorbance and hence the sensitivity is established.

Fiber optic cable guide

Abstract: A fiber optic cable guide has a curved elongated member that fits between the strain relief boot and optical fiber to allow the fiber optical cable to bend without violating the minimum bend radius of the optical fibers. The fiber optic cable guide also retains at least a portion of the fiber optic cable.

Hemodialysis access apparatus

Abstract: This invention is an implanted single or dual lumen device (100) for repeated accessing of a vessel within a body, especially for hemodialysis, plasmapheresis, and other fluid exchange therapy treatments. The device (100) is characterized by having no septum for sealing but having instead a resilient material to form a seal, a smooth streamlined flow path with a low flow resistance, substantially no stagnation points, such that the device is easily, and completely flushed; optionally a gradually changing direction of flow path without introducing flow resistance or stagnation points with a change in direction of up to 20 degrees with a minimum bend radius of twice the lumen diameter or up to 30 degrees with a minimum bend radius of four times the lumen diameter; a positive locking mechanism (104) that accepts, and retains a matching needle apparatus (40). The device is joined to a catheter (240), in most cases, such that fluids can be extracted from or injected into the vessel or vessels to be accessed.

Portal bend limiter/strain reliever for fiber optic closure exit portal

Abstract: A bend limiter/strain reliever is provided for maintaining optical fiber bend limits at exit portals of a optic fiber closure for the closure's entire range of motion, from being fully closed to being fully open. Bend limits are maintained as optical fiber is directed on paths through a closure exit portal between the closure interior and wire brackets on the closure exterior. Fibers are retained, organized and strain relieved by the bend limiter/strain reliever such that directed fiber is maintain at a minimum bend radius on such fiber paths. The curved surface of the bend limiter/strain reliever allows the closure to be accessed without excessive bending of so routed optical fibers. In this manner, optical signal degradation and/or total loss is avoided by limiting the bending of routed optical fiber to radii in excess of a predetermined minimum bend radius. Horizontal members separate the bend limiter/strain reliever into compartments and make it easy to isolate fibers so that they may be efficiently traced and removed during system maintenance.

Fiber Reinforced Polymer Reinforcement for Concrete Structures

Abstract: An experimental program conducted at the University of Manitoba, Canada, to examine the structural performance of fiber reinforced polymer (FRP) stirrups as shear reinforcement for concrete structures is summarized. A total of ten large-scale reinforced concrete beams were tested to investigate the modes of failure and the contribution of the FRP stirrups in the beam mechanism. The ten beams included four beams reinforced with carbon FRP stirrups, four beams reinforced with glass FRP, one beam reinforced with steel stirrups and one control beam without shear reinforcement. The variables are the material type of the stirrups, the material type of the flexural reinforcement, and the stirrup spacing. Due to the unidirectional characteristics of FRP, significant reduction in the strength of the stirrup relative to the tensile strength parallel to the fibers is introduced by bending FRP bars into stirrup configuration and by the kinking action due to inclination of the diagonal shear crack with respect to the direction of the stirrups. A total of 40 specially designed panel specimens were tested to investigate the bend effect on the stirrup capacity, along with two control specimens reinforced with steel stirrups. The variables considered in the bend specimens are the material type of stirrups, the bar diameter, then bend radius, the configuration of the stirrup anchorage, and the tail length beyond the bend portion. A total of 12 specially designed panel specimens were also tested to investigate the effect of the angle of cracks on the stirrup capacity. The two variables considered in this case are material type of the stirrups and the crack angle. Description of the experimental program, test results and design recommendations are presented.

Kink-resistant, high pressure hose construction having a composite, spiral wound innermost reinforcement layer

Abstract: A kink-resistant hose construction adapted for conveying fluids under high pressure which is flexible intermediate a central longitudinal axis to a minimum bend radius. The construction includes a thermoplastic core having an inner surface defining the inner diameter of the hose and an outer surface, and an innermost reinforcement layer disposed radially circumferentially about the outer surface of the core. The innermost reinforcement layer is formed as a composite of at least one metallic wire element and at least one non-metallic fiber element. The metallic wire element is wound helically in one direction over the outer surface of the core at a predetermined pitch angle measured relative to the longitudinal axis to define a series of first turns. Each of these first tuns is spaced-apart from an adjacent first turn to define successive pairs of first turns each having an interstitial area therebetween. The fiber element, in turn, is wound helically over the outer surface of the core in the same direction and at the same pitch angle as the metallic wire element to define a series of second turns each disposed intermediate a corresponding one of the pairs of the first turns or the wire element. The fiber element substantially occupies the interstitial area between each of the pairs of the first turns of the wire element to thereby prevent the wall of the core from being extruded therebetween as the hose is flexed to its minimum bend radius.

Fiber optic cable capable metal raceway system

Abstract: Two-piece metal raceway accommodates fiber optic cable at 90° corner assemblies that include curved side or back walls. The bend radius of these curved walls is two (2) inches or more, and these walls are also formed with stops to locate the raceway base, and to protect the cable from abrasion due to the raceway base flanges. Each corner assembly also includes a cover that anchors the raceway base to the corner assembly.

Fiber-optic cable tray having adjustable components

Abstract: A fiber-optic cable tray having adjustable components that provide flexibility in accommodating changes in length of the routed fiber-optic cable and that ensures a minimum bend radius for the routed cable.

Bend radius guide

Abstract: A bend radius guide provides effective cable management and bend radius control to prevent microbending of fiber optic cables entering and exiting cable distribution enclosures. Using arcuate surfaces, the guide provides bend radius control to prevent against microbending at distribution enclosure openings in directions horizontal or vertical to the enclosure depending upon the placement of the guide. When used in conjunction, bend radius guides prevent microbending in both horizontal and vertical directions concurrently. Bend radius guides used in conjunction can manage a number of fiber cables while still allowing access to individual cables through an angled slot formed by the joining of two guides.

Press working method for magnesium alloy and press working device

Abstract: PROBLEM TO BE SOLVED: To provide a press working method and a press working device for a magnesium alloy by which the metal plate of magnesium alloy is worked with a small bending radius by bending it less times while preventing generation of a crack. SOLUTION: While a plate material 1 to be worked consisting of magnesium alloy, is heated to a working temp. of >=200 deg.C, bending that is set so that successively smaller bending radius is repeated at least two times, to obtain the magnesium alloy having a prescribed bending radius. Concretely, the plate material 1 to be worked is bent at a working temp. of >=200 deg.C at a bending rate of 80 to 100%, affording a primary worked part 7. The primary worked part 7 is bent at a working temp. of >=200 deg.C at a vending rate of 100 to 150%, affording a required press worked part 11, that has a prescribed small radius and the crack is not caused.

Fiber-optic cable routing and storage device

Abstract: A fiber-optic cable routing and storage device that can be used to accommodate the slack of various different lengths of fiber-optic cable and that includes a fiber-optic cable routing path that ensures a minimum bend radius for the routed cable.

Fiberoptic coupler sensor and a measurement method

Abstract: Sensors and sensing apparatus are described, based on fused tapered fibre optic couplers with the taper waist portion formed into a loop or cleaved to provide a reflecting end. Light is typically input to the taper waist portion along a single input fibre, and bending of the loop or cleaved taper waist portion causes changes in the coupling ratio between the ouput fibres. The taper waist portion may be formed into a loop with a small bend radius without loss, and sensors embodying the claimed invention are particularly suitable for in-vivo measurement of pressure, the taper waist portions advantageously being arranged in contact with a membrane which deflects according to surrounding pressure. Further embodiments are described which are suitable for measurement of fluid flow velocity and/or acceleration.

Fiber mini-bend light guide

Abstract: A mini-bend optical arrangement and an associated method are described. This arrangement is designed to change the directional orientation of a light path using optical fiber. A first and a second fiber optic member define first and second light paths, respectively, which first and second members include a numerical aperture and which introduce substantial bend losses upon being bent at less than a predetermined bend radius. The first and second fiber optic members are arranged along the first and second paths preferably bent by less than the predetermined bend radius. A bent fiber optic member including a numerical aperture that is greater than the numerical aperture of the first and second fiber optic members interconnects the first and second fiber optic members so as to define a continuous light path including the first and second light paths with the bent member defining a curved path therebetween such that the bent fiber optic member has a bend radius which is less than the predetermined bend radius but which avoids introducing substantial bend losses. The mini-bend arrangement is useful in highly advantageous miniaturized device configurations. As a first example, a miniaturized add/drop module is introduced. As other examples, miniaturized tree couplers, EDFA modules and WDM modules are introduced.

Pipe inspection device and method

Abstract: A method of inspecting a pipe, by pushing a video camera through the pipe on a cable, with a wire helical coil disposed between the video camera and a stop on the cable, the wire helical coil being long enough to permit passage of the video camera around a first bend. As the video camera is pushed into the pipe and moves around the first bend, a cable stiffener is placed on the cable to stiffen the cable in the first straight section while permitting the cable to move through the cable stiffener. The video camera is then pushed down a second straight section and around a second bend to view a third straight section. The cable stiffener comprises a rod having first and second ends, a straight slot running along the rod from the first end to the second end for receiving a cable, and the rod having an enlarged portion along part of the rod forming a centralizer.

Effect of macro-bending on dispersion of dispersion compensating fibres

Abstract: Using direct measurement, the effect of macro-bending on the dispersion in dispersion compensating fibres was investigated It was shown that even a relatively large bend radius of /spl sim/10 cm can modify the fibre dispersion in the range 1500-1600 nm

Kink resistant high pressure hose

Abstract: A kink-resistant hose construction (10) adapted for conveying fluids under high pressure which is flexible intermediate a central longitudinal axis (12) to a minimum bend radius. The construction includes a thermoplastic core (14) having an inner surface (16) defining the inner diameter of the hose and an outer surface (18), and an innermost reinforcement layer (20) is formed as a composite of at least one metallic wire element and at least one non-metallic fibre element. The metallic wire element is wound helically in one direction over the outer surface of the core a predetermined pitch angle measured relative to the longitudinal axis to define a series first turns. Each of these first tuns is spaced-apart from an adjacent first turn to define successive pairs of first turns each having an interstitial area therebetween. The fiber element, in turn, is wound helically over the outer surface of the core in the same direction and at the same pitch angle as the metallic wire element to define a series of second turns each disposed intermediate a corresponding one of the pairs of the first turns or the wire element. The fiber element substantially occupies the interstitial area between each of the pairs of the first turns of the wire element to thereby prevent the wall of the core from being extruded therebetween as the hose is flexed to its minimum bend radius.

Optic fiber slack storage bracket

Abstract: A slack storage bracket for use in fiber optic cable splice enclosures having a body, mounting members for mounting the slack storage bracket to the enclosure, and opposed radial shelf portions extending outwardly from the body to hold the cable slack. The shelf portions preferably have stops to keep the cable slack from slipping off of the shelf portions. The body of the bracket is preferably an arc which, like the radial shelf portions, have a radius of not less than the minimum bend radius of the cable to avoid damage to the cable.

Bending method of hollow shape, production of sheet back frame and sheet back frame structure

Abstract: PROBLEM TO BE SOLVED: To provide a bending method of a hollow shape in which the hollow shape is bent in a small bending radius without generating a harmful crack, dent, wrinkle, etc., at a curved part, troublesomeness in working is eliminated and thermal effect due to welding is not caused and to provide a sheet back frame production method and a sheet back structure using this hollow shape bending method. SOLUTION: Relating to a side wall parallel to the bending radius direction of a hollow shape 10 (a curved part inside of a side wall 13 and a center part of a side wall 15), at least at a part to be subjected to bending of the hollow shape 10, a valley folded, deformed part T deformed in a hollow part (a second hollow part 10B) inward direction is previously formed along the longitudinal direction of the hollow shape 10, successively, this hollow shape 10 is bent.

Cable strain relief bracket

Abstract: A strain relief bracket for use in conventional and modular furniture applications guards against excessive bending of copper and fiber optic cable. The device is a substantially rigid durable bracket that has an adhesive surface for adhesion to the interior of a furniture wall. The device is bi-planar, having a first section in a first plane, a raised flange section in a second plane, and a second section connecting the first section and raised flange section. A flange at the end of the first section secures the bracket to the edge of an opening in the furniture wall. Cables are secured to the bracket by cable ties that extend through holes provided on the raised flange section. The bi-planar arrangement of the bracket minimizes the bend radius of the cables and thereby strain relieves the cable, adapters, and connectors in the wall.

Temperature compensated optical fiber force sensor

Abstract: The sensor has at least one fibreoptic force transducer with an optical fiber arrangement with light input and light output ends. The force being measured acts on the fiber arrangement and the light transferred from the input end to the output end is measured from the changes in bending radius of an optical fiber. The fiber arrangement has at least one fiber (9a,9b) arranged on an inner surface of a hollow vol. in a stiff outer structure (7). The inner surface has a modified structure (8a,8b) so that a force acting causes fiber bending radius changes. The hollow structure contains a stiff compression structure (5) with smaller dimensions than the hollow chamber's internal dimensions with a rubber-elastic material (6) in the space between them.

Method for determining the radius of curvature of a road

Abstract: of EP0979763The method involves measuring the difference in wheel speeds of at least two vehicle wheels, to derive the yaw rate and hence the bend radius (R). A constant wheel angle is specified for each wheel. The summation period is measured over the wheel angle for each wheel. The transverse slip and hence the radius of the bend are derived from the ratio of the summation periods of a wheel pair.

Method for detecting cornering for a vehicle with an automatic transmission

Abstract: The invention relates to a method for detecting cornering for a vehicle (2) with an automatic transmission. According to the invention, the current radius of a bend is determined based on the wheel speed signals of the front wheels. The beginning of a cornering status is determined when the current bend radius falls below a first limit bend radius and the end of a cornering status is determined when the vehicle has travelled a predetermined distance after exceeding a second limit bend radius.

System and method for limiting protrusion of a fiber-optic cable from a mounting structure

Abstract: A system for minimizing a protrusion of a fiber-optic cable from a mounting structure comprises a fiber-optic connector, an adapter for a fiber-optic connector, and a standoff The standoff positions the adapter and the connector at a fixed distance from a front surface of the mounting structure. A fiber-optic cable is routed from the connector through a penetration extending between the front and the rear surfaces of the mounting structure. The standoff has a minimum length that ensures that the connector does not protrude from the rear surface of the mounting structure. This arrangement allows a curvature to be imposed on the cable as it exits the rear surface. By imposing a curvature equal to the minimum bending radius of the cable, and extending this curvature through an arc of 90 degrees, a protrusion of the cable in a direction normal to the rear surface can be limited to the minimum bending radius of the cable.

Titanium clad steel plate, and its manufacture

Abstract: PROBLEM TO BE SOLVED: To provide the thin titanium clad steel sheet having the critical bend radius below 1.0 t, and its manufacturing method using an existing hot rolling process for steel sheet. SOLUTION: In a manufacturing method for a titanium clad steel sheet, a steel in which the C content is Torr to manufacture a slab, the slab is heated to =5% in hot rolling the slab so that the total draft is >=85%, and the slab is finish-rolled at >=700 deg.C, and the finish-rolled titanium clad steel plate is coiled at >=650 deg.C.

Fiber optic gyroscope

Abstract: A method is disclosed which reduces wavelength ripple in a fiber optic gyroscope by suppressing, as well as reducing the effects of, whispering gallery modes generated by the gyroscope light source. The method functions to increase the radius of bends in existing curved sections of optical fiber used in the light source for a fiber optic gyroscope. This increase in bend radius effectively reduces the amount of core-to-clad-to-core reflected light, which in turn reduces the extent to which whispering gallery modes are generated, thereby reducing a source of wavelength ripple. Reduction of wavelength ripple is also accomplished in the present invention by using a band rejection filter to attenuate one of the bimodal spectral components generated by the gyroscope light source.

Three-point bending type hot bender

Abstract: PROBLEM TO BE SOLVED: To eliminate the need for a foundation work at the time of installation to a factory or the like and to make it possible to carry the device to a site for laying of pipes or the like at need and to execute on site working by installing a three-point bending mechanism section together with a feed mechanism into a common base plate having large rigidity. SOLUTION: A pusher 3 modes on the rails 11 on the base plate 2 by receiving the driving power by a drive assembly 12 transmitted by means of sprockets 13 and chains 14. A pipe 1 delivered to the feed mechanism section A is locally heated by a heating coil 6 and three-point bending rollers 10 apply pressing force on the pipe 1 from its flanks. As a result, a bend is formed at a certain angle in the locally heated section. A series of these operations are repeated while the bending rollers 10 are moved at prescribed loci by the combination of the movements of an X-table 8 and a Y-table 9, by which the bending by a prescribed bending radius is formed at a desired bending angle.

Echelle spectrometer with 2D detector has segmented receiver that is smaller than apex radius of camera mirror center of segmented receiver and that radius forms specified angle

Abstract: An even segmented receiver of an apex of a spherical camera mirror is arranged more remotely at intervals of its half bending radius R(k). R(k) is of O9R(p) and a gap O,9R(p) is selected between centers of an inlet aperture. A segmented receiver is smaller than apex radius of the camera mirror while the center of the segmented receiver forms an angle of 6o.