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Showing papers on "Bend radius published in 2001"


Journal ArticleDOI
TL;DR: In this paper, a 60° photonic-crystal waveguide bend is successfully fabricated based on a photonic crystal slab structure and its bending radius is ∼1μm at a wavelength of λ∼1.55μm.
Abstract: Based on a photonic-crystal slab structure, a 60° photonic-crystal waveguide bend is successfully fabricated. Its bending efficiency within the photonic bandgap is measured, and near 100% efficiency is observed at certain frequencies near the valence band edge. The bending radius is ∼1 μm at a wavelength of λ∼1.55 μm. The measured η spectrum also agrees well with a finite-difference time-domain simulation.

171 citations


Journal ArticleDOI
TL;DR: In this article, the solid flow nonuniformities which develop in lean phase upward flow in a vertical pneumatic conveying line following a horizontal-tovertical elbow were investigated.

114 citations


Journal ArticleDOI
TL;DR: In this paper, the simulation results on pre-bending and hydroforming processes that are used to form an automotive part, a tie bar, are compared with each other using a rotary draw bending machine and a bend die.

87 citations


Patent
28 Mar 2001
TL;DR: In this article, a cable manager (10) provides horizontal cable management of adjacent patch panels or network equipment on network distribution racks, including a central section (16) and a front cable routing section (12) and is mounted on a network rack, such as an EIA rack.
Abstract: A cable manager (10) provides horizontal cable management of adjacent patch panels or network equipment on network distribution racks. The cable (10) manager includes a central section (16) and a front cable routing section (12) and is mountable on a network rack, such as an EIA rack. The central section (16) has a longitudinal width sized to fit within the network rack, a front side, a rear side, and rack mounting holes (50) provided on opposite longitudinal ends of the central section. The front cable routing section (12) extends from the front side of the central section and includes a plurality of spaced fingers (30,40) having an arcuate surface that provides bend radius control. A slit provides flexibility to the fingers. Ears extend laterally from the fingers. The cable manager can also include a rear cable routing section that includes a second plurality of spaced fingers. One or more passthrough openings can be provided in the central section to allow routing of cabling from the front section to the rear section. Either or both of the front and rear sections can include a removable cover. The cover may be hingedly connected.

87 citations


Journal ArticleDOI
TL;DR: In this paper, the performance of small bending radius helical coil-pipe used in HTR-10 steam generator experimental facility was investigated and it was confirmed that the critical Reynolds number is much greater than in a straight pipe and is a function of De.
Abstract: Helical steam generator or helical heat exchanger is extensively used in high-temperature gas cooling reactor, fast breeder reactor, pressurized water reactor using in ship propulsion and areas of electro-power, chemical industry and petroleum industry. The purpose of this paper is to research the hydraulic performance of small bending radius helical coil-pipe used in HTR-10. Research for hydraulic performance of small bending radius helical pipe was carried out on the HTR-10 steam generator experimental facility. Based on the experimental results, it was confirmed that for helical pipe the critical Reynolds number (Re) is much greater than in a straight pipe and is a function of De. Formulas for Re of single-phase flow structure transition, friction coefficient of single-phase flow, and two-phase flow friction factor are obtained. Experience formulas of small bending radius helical pipe are recommended for design and research.

80 citations


Journal ArticleDOI
TL;DR: In this article, the characteristics of the particle flow in a horizontal pipe following a 90° vertical-to-horizontal elbow were investigated both numerically and experimentally, and it was observed that the strong rope created by the elbow disintegrates within an axial distance of 10 pipe diameters.

78 citations


Journal ArticleDOI
TL;DR: In this paper, a rigorous study of polarization rotation in deeply etched semiconductor optical waveguide bends has been carried out and results are presented, using the finite element-based fully vectorial beam propagation method.
Abstract: A rigorous study of polarization rotation in deeply etched semiconductor optical waveguide bends has been carried out and results are presented, using the finite element-based fully vectorial beam propagation method. It has been shown that by careful adjustment of the waveguide width, the slant sidewalls and the bending radius, a very compact polarization rotator design, only 60 /spl mu/m long, with extremely low overall loss, and nearly 100% polarization conversion ratio can be achieved.

72 citations


Journal ArticleDOI
TL;DR: In this article, a closed-form expression for the bending angle is proposed to better understand the deformation characteristics such as wall thickness variation, cross-section ovalization, bending radius, and asymmetry.
Abstract: Laser bending of tubes is a process in which laser-induced thermal distortion is used to bend tubes without hard tooling or external forces. Mechanisms of the process are examined to better understand the deformation characteristics such as wall thickness variation, cross-section ovalization, bending radius, and asymmetry. Factors important to these characteristics are experimentally and numerically investigated. Temporal and spatial distributions of temperature and stress/strain obtained from experimentally validated simulation models are also used to better understand additional phenomena accompanying the process, and to help devise ways to improve the process such as reducing asymmetry. A closed-form expression for the bending angle is proposed.

69 citations


Patent
07 Mar 2001
TL;DR: In this paper, a fiber optic wall mount cabinet includes a heavy gauge metal enclosure having a back wall, top and bottom walls, side walls, and covers, and a patch panel wall disposed substantially parallel to a side wall and extending between the top wall and bottom wall separates the interior of the cabinet into an incoming chamber and exiting chamber.
Abstract: A fiber optic wall mount cabinet includes a heavy gauge metal enclosure having a back wall, top and bottom walls, side walls, and covers. A patch panel wall disposed substantially parallel to a side wall and extending between the top and bottom wall separates the interior of the cabinet into an incoming chamber and exiting chamber. Both sides of the patch panel wall include a plurality of attachment sites to which a connector mounting plate or bend radius control clip may be releasably secured. The bend radius control clip may comprise a bend radius control arm adapted to prevent bending of fiber optic cables terminated on the patch panel wall. The cabinet further comprises a first cover hingedly connected to the side wall and a second cover hingedly connected to the back wall. In a closed position, both the first cover and second cover completely enclose the incoming chamber and exiting chamber, respectively.

66 citations


Journal ArticleDOI
TL;DR: In this article, an energy approach is presented to provide the minimum bending radius, which does not yield wrinkling in the bending process, as a function of tube and tooling geometry and material properties.
Abstract: Thin-walled tube bending has found many of its applications in the automobile and aerospace industries. This paper presents an energy approach to provide the minimum bending radius, which does not yield wrinkling in the bending process, as a function of tube and tooling geometry and material properties. A doubly-curved sheet model is established following the deformation theory. This approach provides a predictive tool in designing/optimizing the tooling parameters in tube bending.

57 citations


Patent
31 Jan 2001
TL;DR: In this article, a disk drive is disclosed comprising an actuator arm, a head coupled to the actuator, and a voice coil motor for actuating the arm to move the head.
Abstract: A disk drive is disclosed comprising an actuator arm, a head coupled to the actuator arm, and a voice coil motor for actuating the actuator arm to move the head. The voice coil motor comprises a first magnet for generating a first magnetic flux, and a yoke comprising a magnetic flux conductor for guiding the first magnetic flux. The magnetic flux conductor comprises a body and a top and bottom protruding plate portions, wherein the body and the plate portions are integrally formed. The body defines, in vertical cross section, a primary bend having a primary bend radius and at least one secondary bend having a secondary bend radius.

Patent
10 Sep 2001
TL;DR: In this article, a non-prismatic radial folded fin heat sinks include fin arrays comprised of folded fins joined to a thermally conductive central core, which can have either a constant or variable bend radius.
Abstract: Non-prismatic radial folded fin heat sinks include fin arrays comprised of folded fins joined to a thermally conductive central core. The fin arrays can have either a constant or variable bend radius. The non-prismatic radial folded fins can be made by stamping patterns into sheet metal prior to folding the sheet metal in opposite directions at various intervals to form outer and inner folds. By arranging the fins in a non-prismatic radial pattern around the central core, airflow generated by an overhead fan is better utilized, thus improving the cooling effect of the device.

Patent
26 Jun 2001
TL;DR: A cable management cabinet assembly for telecommunications equipment is described in this article, where a cable management bracket having an elongated member is fastened to the support members, and gaps sized to receive telecommunications cables are positioned between the fingers.
Abstract: A cable management cabinet assembly for telecommunications equipment. The assembly includes a cabinet frame with sidewalls and vertical support members. A cable management bracket having an elongated member is fastened to the support members. A plurality of fingers project outwardly from the elongated member. The fingers are spaced apart along the length of the elongated member. Gaps sized to receive telecommunications cables are positioned between the fingers. Bend radius limiters are preferably connected to the fingers to prevent cables passing through the gaps from being bent beyond predetermined bend radius requirements. The bracket defines a vertical cable pathway between the side walls and the fingers for guiding cables within the cabinet.

Patent
16 Feb 2001
TL;DR: A cover fitting for connecting more than one raceway includes an L-shaped top having first and second curved grooves extending along the inner surface of the top and a plurality of hooks extending outwardly from the inner surfaces for engaging a portion of each raceway base as discussed by the authors.
Abstract: A cover fitting for connecting more than one raceway includes an L-shaped top having first and second curved grooves extending along the inner surface of the top and a plurality of hooks extending outwardly from the inner surface for engaging a portion of each raceway base. The cover fitting further includes first and second opposing sides extending from the inner surface of the top. The cover fitting can be used with a fitting base received in first and second grooves for situations requiring a specific bend radius, or in applications without a fitting base, where there are no bend radius requirements.

Patent
26 Oct 2001
TL;DR: An apparatus for managing and measuring fiber optic cable includes a mounting base for receiving and retaining a variety of fiber cassettes capable of holding optical components having fiber optic cables emanating therefrom as mentioned in this paper.
Abstract: An apparatus for managing and measuring fiber optic cable includes a mounting base for receiving and retaining a variety of fiber cassettes capable of holding optical components having fiber optic cables emanating therefrom. The apparatus includes a pair of interchangeable marking mandrels spaced from the fiber cassette and having circumferences that exceed the minimum bend radius of the fiber optic cables. Each marking mandrel has marking grooves formed on its periphery so that the fiber optic cable may be marked at a predetermined location for future splicing of the cable. The apparatus further includes fiber take up mandrels connected to the mounting base, each fiber take up mandrel having a circumference that exceeds the minimum bend radius of the fiber optic cables. The marked fiber optic cables may be temporarily wound around the circumference of the fiber take up mandrels to prevent entanglement and keep the fiber out of the operator's way while another cable is being marked. The apparatus also includes a pair of fiber retainer rails interposed between the fiber cassette and the fiber take up mandrels for guiding the fiber optic cable from the fiber cassette to the fiber take up mandrels. Each of the fiber retainer rails has a resilient rail portion that protects the fiber optic cables from damage.

Journal ArticleDOI
TL;DR: By using an efficient vector finite-element-based beam-propagation method, an improved design of a polarization converter is presented that achieves nearly 100% polarization conversion ratio with no appreciable radiation loss and a bending angle of less than 180 degrees.
Abstract: By using an efficient vector finite-element-based beam-propagation method, we present an improved design of a polarization converter. This design relies on the use of a single-section deeply etched bent semiconductor waveguide with slanted sidewalls. By careful adjustment of the bend radius, the waveguide width, and the sidewall angle we obtained a nearly 100% polarization conversion ratio with no appreciable radiation loss and a bending angle of less than 180°.

Journal ArticleDOI
TL;DR: In this article, the behavior of a pipe bend with bend factor h = 0.1615 (D=16 in, R=24 in, and t =0.41 in) subjected to out-of-plane bending and internal pressure is studied, taking geometric and material nonlinearity into account, using the finite element code ABAQUS.
Abstract: The behavior of a pipe bend, with bend factor h=0.1615 (D=16 in., R=24 in, and t =0.41 in. ), subjected to out-of-plane bending and internal pressure is studied, taking geometric and material nonlinearity into account, using the finite element code ABAQUS. Material behavior is taken as elastic-perfectly plastic. The distribution of stress and strain along the axial direction and across the thickness of the bend is studied, with and without internal pressure, at the onset of yielding and at instability. Before instability is reached, through-the-thickness yielding appears at many points. The loaded end of the bend is found to be the most severely strained cross section. The circumferential distribution of stress and strain, and its variation with increased moment loading are then investigated for that section, at internal pressure values of zero and 1200 psi.

Patent
Nadir Shah1
31 Aug 2001
TL;DR: In this paper, a fiber optic cable winding tool with a disk-shaped base and a pair of semi-circular spools mounted on the base is described, where the spools are radially adjustable toward and from the central axis of the base by providing spools on rails connected to and radially extending away from the base.
Abstract: A fiber optic cable winding tool having a disk-shaped base and a pair of semi-circular spools slidably mounted on the base. The spools are radially adjustable toward and from the central axis of the base by providing the spools on rails connected to and radially extending away from the central axis of the base. Each spool has a fiber optic cable contacting surface with a radius of curvature exceeding a minimum bend radius of the fiber optic cable. A pair of linkage arms connect to each spool and further connect to a slide block spaced from the spools. One of the spools is capable of being retained against the base once the desired diameter of the winding is located. The retained spool, in conjunction with the linkage arms and slide block, prevent the other spool from sliding relative to the base. This way the diameter of the spools can be set and the fiber optic cable may be wound thereon. The rails permit the spools to be radially collapsed towards the central axis of the disk-shaped base after winding the fiber optic cable to permit removal of the fiber optic cable from the spools.

Patent
Gary Kles1
31 Aug 2001
TL;DR: In this paper, a fiber optic cable winding tool with concentric upper and lower disk-shaped bases that are rotatable relative to each other is presented, where four quarter-circle spools are slidably mounted on the upper base, and are radially adjustable towards and from the central axis of the upper-base via radial slots formed in the lower-base.
Abstract: A fiber optic cable winding tool having concentric upper and lower disk-shaped bases that are rotatable relative to each other. Four quarter-circle spools are slidably mounted on the upper base, and are radially adjustable towards and from the central axis of the upper base via radial slots formed in the lower base. Each spool has a fiber optic cable contacting surface with a radius of curvature exceeding a minimum bend radius of the fiber optic cable. The radial slots communicate with corresponding arcuate slots formed in the lower base, and roller guides are provided through each radial slot and its corresponding arcuate slot and connects to a corresponding spool. When the upper and lower bases are rotated relative to each other, the spools move either towards or away from the central axis of the upper base, enabling a spool a diameter to be set. A thumb screw is also provided to bear against the rear base and maintain the desired diameter setting. The tool further includes a travel stop guide formed on the periphery of the upper disk-shaped base to prevent the upper and lower disk-shaped bases from rotating relative to each other, enabling predetermined diameters to be set. The radial and arcuate slots permit the spools to be radially collapsed towards the central axis of the upper disk-shaped base after winding the fiber optic cable to permit removal of the fiber optic cable from the spools.

Patent
22 Aug 2001
TL;DR: In this paper, a cable management apparatus guides and supports cables when mounted as part of an electronics assembly, where cables are organized such that individual cables or groups of cables may be associated with specific electronic components within the electronics assembly.
Abstract: A cable management apparatus guides and supports cables when mounted as part of an electronics assembly. Preferably, cables enter the electronics assembly through the rear of the electronics assembly and through each side of the electronics assembly. Cables entering the electronics assembly are guided to the electronic components within the electronics assembly. Cables are organized such that individual cables or groups of cable may be associated with specific electronic components within the electronics assembly. Cables or groups of cables associated with specific electronic components within the electronics assembly may be accessed individually while handling a large bundle of cables. In one embodiment of the present invention fiber optic cables are supported such that a minimum bend radius is maintained. Thus, in accordance with one specific aspect of the present invention, fiber optic cables may be supported and organized as part of an electronics assembly.

Patent
27 Dec 2001
TL;DR: In this paper, a wall defining the wall has a center of curvature and a radius of curvatures, and a distance between the center of the hole and the center curvature of the wall is selected to form a deeper compartment to improve the torque-bearing capacity.
Abstract: A head of a wrench comprises a hole having a center and a radius. The head further includes a compartment communicated with the hole. A wall defining the compartment has a center of curvature and a radius of curvature. A ratio between the radius of curvature of the wall and the radius of the hole is equal to or greater than 0.5, but less than 1. A distance between the center of the hole and the center of curvature of the wall is selected to form a deeper compartment to thereby improve the torque-bearing capacity.

Journal ArticleDOI
TL;DR: In this article, an analytical model for the determination of local postbuckling and suck-in deformations in bending is presented based on the deformation theory of plasticity combined with an energy method using appropriate shape functions.

Patent
10 Apr 2001
TL;DR: In this paper, a single V-shaped tube is bent in a plane and has an inlet section (11), an outlet section (12), an in-let bend (13), a vertex bend (15), and a respective tube section (16, 17 ) between the inlet bend and the outlet bend.
Abstract: A single V-shaped tube ( 1 ) is bent in a plane and has an inlet section ( 11 ), an outlet section ( 12 ), an inlet bend ( 13 ), an outlet bend ( 14 ); a vertex bend ( 15 ) and a respective tube section ( 16, 17 ) between the inlet bend and the outlet bend. The distance between the vertex of the vertex bend and the inlet/outlet axis can be great. Two clamping bodies ( 2, 3 ) are clamped onto the tube sections defining a tube section. Flat bodies ( 31, 32 ) are fixed onto the clamping bodies ( 2, 3 ). Fixed to the flat bodies is an opposed-action body ( 41 ) which extends along the axis of symmetry (I—I) up to the vertex bend, where it supports a first portion of an exciter assembly ( 50 ) or a seismic exciter ( 50 ′) which excites the tube section in a third mode of vibration at an associated natural frequency f 3 . A sensor support ( 61 ) and a sensor support ( 62 ) are fixed to the flat body ( 31 ). A velocity or displacement sensor ( 71, 72 ) is fixed to the tube section and the sensor supports. Inlet section and outlet section are held by a supporting frame ( 35 ) to which a housing ( 8 ) is fixed.

Patent
01 Jun 2001
TL;DR: In this article, a reconfigurable modular bend radius control fixture system allows for customization of bend module sections to achieve a variety of configurations with only a minimal number of different parts.
Abstract: A reconfigurable modular bend radius control fixture system allows for customization of bend module sections to achieve a variety of configurations with only a minimal number of different parts. The system includes at least one main section having a curved surface with a predetermined radius that provides a first bend radius control surface and side walls, at least one straight side plate section removably mountable to the side walls of the main section, the side plate section having a side wall that extends beyond the curved surface when mounted, and at least one bend radius control side plate removably mountable to the side walls of the main section. The bend radius control side plate section forms a second bend radius control surface. These sections can be mounted in various configurations to form a bend radius control fixture that can be mounted to a mount member of a cable management system, such as a ladder rack. The fixture is particularly suited for assisting management of sensitive cabling, such as fiber optic cabling or category 5 and 6 cabling.

Patent
12 Jan 2001
TL;DR: In this paper, an arcuate member of radius greater than or equal to the minimum bend radius of a prescribed cable is used to provide microbending and bend radius protection for cables in a cable distribution or management system.
Abstract: A device for providing microbending and bend radius protection for cables in a cable distribution or management system. The device includes an arcuate member of radius greater than or equal to the minimum bend radius of a prescribed cable, a plurality of flanges disposed on the arcuate member perpendicular to the longitudinal axis of the arcuate member, a quarter turn fastener, an opening for receiving the quarter turn fastener, a plurality of protuberances, and a plurality of recesses for receiving the protuberances.

Patent
16 Mar 2001
TL;DR: A device for storing and deploying cable, including but not limited to optical fiber cable, is described in this paper, which includes a substantially planar bottom support surface having juxtaposed thumb segments and an intervening finger segment.
Abstract: A device for storing and deploying cable, including but not limited to optical fiber cable The device includes a substantially planar bottom support surface having juxtaposed thumb segments and an intervening finger segment An outer wall is affixed to the bottom surface about its perimeter and extends upwardly therefrom A substantially circular guide wall is disposed on the bottom surface extending upwardly therefrom A substantially circular inner wall is concentrically arranged with respect to the guide wall A top flange is joined to the support surface by the outer wall and, together with the thumb segments, form entry and exit ports for the cable The guide wall and the inner wall define a guide track that is dimensioned so as to enable continuous adjustment of variable lengths of cable in an area of the device bounded by the guide track, the outer wall and a transverse barrier that extends the length of the finger segment The guide track operates to secure the cable in the device once an appropriate length has been accumulated or deployed

Patent
19 Mar 2001
TL;DR: In this paper, a system and a method for increasing suspension resonance frequencies of a head suspension assembly of a disc drive includes, in one example embodiment, attaching a base plate to an actuator arm assembly of the disc drive such that the base plate including the actuator arms assembly are in actuating relationship with a rotating disc of the drive.
Abstract: A system and a method for increasing suspension resonance frequencies of a head suspension assembly of a disc drive includes, in one example embodiment, attaching a base plate to an actuator arm assembly of the disc drive such that the base plate including the actuator arm assembly are in actuating relationship with a rotating disc of the disc drive. A two-piece suspension member having a first and second pieces is attached to the base plate. A gimbal is attached to the two-piece suspension member such that a predetermined bendable area is formed between the first and second pieces and on the gimbal having a stiffer preload bend radius. A stiffer preload bend radius provides a higher stiffness-to-mass ratio without increasing the spring rate of the head suspension assembly to increase suspension resonance frequencies of the head suspension assembly to fall outside a bandwidth of a servo drive to reduce off-track motion of the head suspension assembly during track follow-and-seek operations of the disc drive.

Patent
30 Apr 2001
TL;DR: In this article, a bend radius protection system for multiple applications with fiber optic cables is proposed, which includes a first inwardly facing curved passageway wall and a passagway base surface at the first end of the base framework; a first bend radius guide in the base frame; and a first radius guide corresponding to and inserted in the first bending radius guide groove in base framework.
Abstract: A bend radius protection system for multiple applications with fiber optic cables, and which includes a first inwardly facing curved passageway wall and a passageway base surface at a first end of the base framework; a first bend radius guide groove in the base framework; and a first bend radius guide corresponding to and inserted in the first bend radius guide groove in the base framework, the first bend radius guide having an outwardly facing curved surface; wherein the first inwardly facing curved passageway wall, the passageway base surface and the outwardly facing curved surface, define a fiber optic cable passageway with an opening. The invention may further include a first grooming arm rotatably mounted to the base framework and disposed across the opening of the passageway such that when the first grooming arm is rotated, the forward edge urges fiber optic cables protruding through the opening back into the passageway.

Journal ArticleDOI
TL;DR: In this paper, the authors used Raman microspectroscopy to determine the volumetric micro-strain distribution in mechanically stressed silicon microstructures and demonstrated that silicon beam structures incorporating a 90° bend will experience a non-uniform stress distribution along the bend radius for small radii of curvature.
Abstract: Raman microspectroscopy has been used to determine the volumetric micro-strain distribution in mechanically stressed silicon microstructures. Data are presented as strain images with a spatial resolution of around 0.8 µm. A useful correlation is demonstrated between finite-element analysis calculations of volumetric strain and Raman shift. The results demonstrate that silicon beam structures incorporating a 90° bend will experience a non-uniform stress distribution along the bend radius for small radii of curvature.

Patent
05 Nov 2001
TL;DR: In this paper, a bend radius control member for controlling the bend radius of an optical fiber cable including a deformation resistant heat shrunk outer jacket wrapped around the optical fiber is presented.
Abstract: A bend radius control member for controlling the bend radius of an optical fiber cable including a deformation resistant heat shrunk outer jacket wrapped around the optical fiber cable. The heat shrunk outer jacket has a desired bend radius curvature.