United Technologies Corporation

Sikorsky Aircraft Corporation

Charles J Isabelle

Jules G Kish

Stephen R Sammataro

Francis E Byrnes

Clark VanTine Cooper

William L Noehren

Robert A Stone

Hugh L Kearney

Ralph D Costanza

An isolated ring gear (60) for a planetary gear drive system (12), which isolated ring gear (60) is operative transferring torque loads and reducing the transmission of high frequency vibrations from the planetary pinions (36) of the drive system (12) to an adjacent support (50). The isolated ring gear (60) includes and inner ring segment (62), an outer ring segment (64) and a plurality of spring elements (66) disposed between and integrally formed with the inner and outer ring segments (62, 64). The inner ring segment (62) has a plurality of gear teeth (62.sub.T) for being disposed in intermeshing combination with the teeth (3b.sub.T) of the planetary pinions (36) and the outer ring segment (64) is rigidly affixed to the adjacent support structure (50). The spring elements (66) are operative to transfer torque loads from the inner ring segment (62) to the outer ring segment (64) and, furthermore, provide a torsionally soft load path for reducing the transmission of high frequency vibrations from the inner ring segment (62) to the adjacent support structure (50). The isolated ring gear (60) is fabricated by the steps of: forming a ring-shaped blank of metallic material, grinding a series of gear teeth (62.sub.T) about an inner diameter of the ring-shaped blank and selectively removing material from the ring-shaped blank to form the plurality of spring elements (66), thereby segmenting the blank into the inner and outer ring segments (62, 64). The preferred fabrication method includes wire electro-discharge machining.

Method of making an isolated ring gear for planetary gear drive systems

A coil spring (50) for use in an overrunning spring clutch assembly having a central arbor (16) for centering and supporting the coil spring (50) in an overrunning operating mode. The coil spring (50) includes teaser coils (52) disposed at each end thereof, central coils (54) disposed intermediate the teaser coils (52), and transition coils (56) disposed between and adjoining the teaser coils (52) and the central coils (54). The coil spring (50) is characterized by each of the transition coils (56) having an interface surface (56.sub.IS) being substantially complementary to a corresponding external bearing surface (16.sub.ES) defined by the central arbor (16) of the spring clutch assembly. Such substantially complementary relationship limits the radial deflection of the transition coils (56) in the overrunning operating mode, thereby reducing vibratory bending stresses in the coil spring (50).

Coil spring for overrunning spring clutches

An isolated ring gear (60) for a planetary gear drive system (12), which isolated ring gear (60) is operative transferring torque loads and reducing the transmission of high frequency vibrations from the planetary pinions (36) of the drive system (12) to an adjacent support (50). The isolated ring gear (60) includes and inner ring segment (62), an outer ring segment (64) and a plurality of spring elements (66) disposed between and integrally formed with the inner and outer ring segments (62, 64). The inner ring segment (62) has a plurality of gear teeth (62.sub.T) for being disposed in intermeshing combination with the teeth (32b.sub.T) of the planetary pinions (36) and the outer ring segment (64) is rigidly affixed to the adjacent support structure (50). The spring elements (66) are operative to transfer torque loads from the inner ring segment (62) to the outer ring segment (64) and, furthermore, provide a torsionally soft load path for reducing the transmission of high frequency vibrations from the inner ring segment (62) to the adjacent support structure (50).

Isolated ring gear for planetary gear drive systems

An acoustic isolator is incorporated between a noise generating device and a support structure, such as between a transmission housing and an airframe. The isolator has a first fitting which attaches to the noise generating device, and a second fitting which attaches to the support structure, with an acoustic attenuation member disposed therebetween. Preferably, a first elastomer member is disposed between a pair of vertical walls of the first and second fittings. Optionally, a second elastomer member is disposed between an upper surface of the supporting structure and a lower surface of the second fitting such that horizontal loads are reacted therethrough. Alternatively the first and second elastomers comprise a spherical elastomer member and a cylindrical elastomer member in the form of a spherical bearing. The acoustic isolator thus allows rigid attachment of the adjacent structures yet provides acoustic isolation of complex forces which would normally transmit noise through the structure, particularly those from the vertical, lateral and fore/aft directions. Utilizing the inventive acoustic isolator, noise transmission through the support structure can be substantially reduced.

Elastomeric acoustic insulator

One broad-beam ion deposition coating method (10) for depositing diamond-like-carbon (DLC) coatings (124) on the dynamic surfaces (120S) of articles (120) subject to adherence difficulties includes the steps of: (12) preliminarily conditioning the dynamic surface (120S) for broad-beam ion deposition; (14)inserting the article (120) in a deposition chamber (102); (16) evacuating the deposition chamber (102) to a predetermined base pressure; (18) ion sputtering conditioning of the dynamic surface (120) by ionizing an inert gas to form an ion beam (104B) having a predetermined beam current density and accelerating energy and directing the ion beam (104B) onto the dynamic surface; (20) depositing an interface layer (122) on the dynamic surface (120S) by ionizing a first gas to form an ion beam (104B) having a predetermined beam current density and accelerating energy, and directing the ion beam (104B) onto a target (118) to dislodge atoms therefrom, the dislodged atoms depositing on the dynamic surface (120S) to form the interface layer (122); and (22) depositing a DLC coating (124) on the interface layer (122) by ionizing a carbon-based gas to form an ion beam (104B) having a predetermined beam current density and accelerating energy and directing the ion beam (104B) for deposition of carbon ions (C+) onto the interface layer (122) to form the DLC coating (124) thereon.

Broad-beam ion deposition coating methods for depositing

A self-scavenging, hybrid lubrication subsystem for a main transmission gearbox includes a sump fabricated as an integral extension of the lower portion of the gearbox wherein the sump dynamic fluid level is above the gearbox bottom. The interior sidewall of the lower gearbox is modified to include a cylindrical segment having a first radius, a throat segment having a second radius, and a transition segment contiguous with the cylindrical and throat segments. The radial discontinuity between the cylindrical and throat segments defines a nozzle inlet that directs the outflow of lubricating medium in the gearbox bottom to the sump via a nozzle. The outflow end of the nozzle is positioned above the sump dynamic fluid level. Housed within the lower gearbox is a planetary gear train that includes an annular planetary carrier plate having a deflection plate mounted thereto. The periphery of the carrier plate and the cylindrical and throat segments in combination form primary and restricted flow channels. Interaction between the deflection plate and the gearbox bottom exerts a viscous pumping action on the lubricating medium in the gearbox bottom causing it to flow outwardly into the primary and restricted flow channels. Interaction between the periphery of the rotating carrier plate and the structurally-modified sidewall exerts a viscous pumping action on the lubricating medium in the flow channels causing it to flow therethrough. Substantially all of the lubricating medium flowing through the primary flow channel is diverted through the nozzle to the sump.

Self-scavenging, hybrid lubrication subsystem

A fail safe, segmented drive shaft system includes a segment support assembly (16) comprising a ball bearing (26), for primary rotation, disposed within a journal bearing (28), for secondary rotation, which is disposed within an elastomeric damper (30) that has a vibration probe (34) placed in it for failure detection, and a coupling assembly (18) comprising a flexible diaphragm (66, 67) for primary, flexible coupling between segments and gear teeth (72, 73) which engage for secondary coupling upon failure of the diaphragm (66, 67). The teeth are not concentric with the rotational axis, so vibration indicates failure of the primary flexible coupling.

Fail safe drive shaft system

The topology of parallel axis gears, such as spur and helical gears is modified to produce quieter and more smoothly operating gear sets with more uniform load distribution. A finite element analysis of the gear in its operating mode is made to produce a plot of radial and tangential deflections of the pinion and gear tooth surfaces which will occur when the gears are loaded during operation. The resultant plot is then inverted to produce a plot, or set of coordinates, which will define the path of travel of the gear tooth grinding wheel, which path is a mirror image of the plot of the finite element analysis. The resulting gears, when subjected to operating loads, will thus be deflected tangentially and radially to their optimum operating, or theoretical true involute, positions so as to produce quieter, smoother, and more evenly loaded gear trains.

Gear tooth topological modification

An elastomeric load sharing device, interposed in combination between a driven gear and a central drive shaft to facilitate balanced torque distribution in split power transmission systems, includes a cylindrical elastomeric bearing and a plurality of elastomeric bearing pads. The elastomeric bearing and bearing pads comprise one or more layers, each layer including an elastomer having a metal backing strip secured thereto. The elastomeric bearing is configured to have a high radial stiffness and a low torsional stiffness and is operative to radially center the driven gear and to minimize torque transfer through the elastomeric bearing. The bearing pads are configured to have a low radial and torsional stiffness and a high axial stiffness and are operative to compressively transmit torque from the driven gear to the drive shaft. The elastomeric load sharing device has spring rates that compensate for mechanical deviations in the gear train assembly to provide balanced torque distribution between complementary load paths of split power transmission systems.

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Winsted, CT, United States of America

Charles J Isabelle