Abstract: A multi-speed, power-driven tool may include a transmission mechanism that transmits power from a motor to an output device. A speed selection mechanism may be coupled to the transmission mechanism, to control a speed reduction through the transmission mechanism, and an output speed of the tool. The transmission mechanism may employ a compound, stepped, planetary gear assembly, to provide for an axially compact arrangement of transmission mechanism components, to reduce an axial length of the tool. The speed selection mechanism may employ a multi-staged grounding device, corresponding to the reduced axial length of the transmission mechanism.

Abstract: Provided are an electromechanical brake and a vehicle including the same. An electromechanical brake according to an embodiment of the present disclosure includes a pair of brake pads disposed at two opposite sides of a disc and include a hollow motor configured to provide rotational driving power and having an internal space penetratively formed in a direction in which a rotation axis extends, a nut configured to rotate about the rotation axis of the motor, a Power train coupled to a front side of the motor and configured to transmit the rotational driving power of the motor to the nut, and a pressing screw coupled to the nut and configured to advance or retreat toward the brake pad.

Abstract: Provided are an electromechanical brake and a vehicle including the same.

Abstract: A structure includes a transmission axle rotatably mounted at a center of a housing. The transmission axle includes a sun gear mounted thereon. An internally-toothed ring track is fixed to an inner circumference of the housing. A planetary gear set is arranged between the sun gear and the internally-toothed ring track. The planetary gear set includes a plurality of stepped planetary gears arranged around the sun gear for self-spinning and orbiting around the sun gear. Each stepped planetary gear includes a first toothed portion meshing with both the sun gear and the internally-toothed ring track and a second toothed portion rotatable in unison with the first toothed portion. An output member is fit over the planetary gear set and includes an inner circumference formed with an internal toothed circumference meshing with the second toothed portion of each stepped planetary gear.

Abstract: An actuator is provided, in which second support shafts are protruded to an output shaft side in an axial direction of a second planetary carrier. A power transmission member having convex portions which are protruded radially outward and receive rotation forces from the second support shafts are arranged on a second planetary carrier side of the output shaft in the axial direction. An elastic member is arranged between the second support shafts and the convex portions in a rotation direction of the output shaft. Therefore, the rotation force of the second planetary carrier due to rotation drive of an electric motor is transmitted from the second support shafts to the convex portions of the power transmission member via the elastic member.

Abstract: A mechanical reduction gear for a turbomachine, in particular for an aircraft, this reduction gear including a sun gear having an axis of rotation, a ring gear which extends around the sun gear and which is configured to be fixed in rotation around the axis, planet gears which are in mesh with the sun gear and the ring gear and which are held by a planet carrier which is configured to be fixed or in rotation around the axis, each planet gear including a first toothing of average diameter D1 for the meshing with the sun gear, and a second toothing of average diameter D2, different from D1, for the meshing with the ring gear, wherein the first and second toothings of each planet gear include herringbone teeth and are symmetrical with respect to a plane perpendicular to the axis and passing substantially in the middle of the planet gear.

Abstract: A food processor assembly is provided with a bowl with a substrate sized to be supported upon a blender base, and a sidewall to collectively define a bowl cavity to receive food products. A planetary gear transmission is supported upon the bowl substrate with a rotary input sized to receive a blender rotary output. A first transmission rotary output extends into the bowl cavity to provide a reduced rotation from the rotary input. A blade is connected to the first transmission rotary output for rotation relative to the bowl substrate to perform a cutting operation to a food product. The blade has a first cutting edge formed adjacent the first transmission rotary output to perform a continuous cutting operation to the food products. The blade has a second cutting edge spaced radially from the first transmission rotary output to perform a sequential cutting operation to the food products.

Abstract: There is provided a mechanical paradox planetary gear mechanism, including: a sun gear configured to be rotatable together with rotation of an input shaft; a plurality of first planetary gears arranged around the sun gear at equal intervals, and configured to rotate about their own axes while revolving around the sun gear in a state in which the first planetary gears mesh with the sun gear; a first internal gear arranged around the plurality of first planetary gears, and configured to mesh with the plurality of first planetary gears; a second internal gear arranged in the same axis as the first internal gear; and a plurality of second planetary gears respectively arranged on the same axes as the plurality of first planetary gears, and configured to mesh with the second internal gear.

Abstract: An aircraft engine reduction gearbox includes a power input and a power output, and an epicyclic gear train engaged with the power input and the power output. The epicyclic gear train includes a sun gear engaged with the power input and centrally disposed to define a center axis of the epicyclic gear train. Compound planet gears are mounted to a carrier and rotatable about respective planet gear axes. Each compound planet gear has an input gear in meshed engagement with the sun gear, and output gears axially spaced from the input gear. Ring gears are axially spaced apart and rotatable about the center axis. The ring gears are engaged with the power output. Each ring gear is in meshed engagement with one of the output gears.

Abstract: A series for an epicyclic gear train and a planet gear carrier consisting of a carrier base with a plurality of axial receptacles for bearing pins of planet gears and a depression for receiving an axial section of a pinion. The object of the present invention is to specify a planet gear carrier, which shifts the boundaries of the reduction range such that a greater variation of the reduction gear ratios is possible, wherein an economical process is used and reliable production is ensured. Also described is a series of planetary gear trains having the same properties. In the case of series, the number of components is in particular to be minimized by increasingly using common parts that can be combined with other common parts.

Abstract: A high-ratio differential reducer is provided. A carrier is connected to an input shaft. At least one planetary gear is supported to be rotatably supported by the carrier in an eccentric state from the carrier. A fixed annular gear meshes with the planetary gear in a state of being coaxially arranged with the carrier. A rotating annular gear meshes with the planetary gear in a state of being coaxially arranged with the fixed annular gear and has the number of teeth set by Equation below: Zo=Zf±Np??(1), where Zo is the number of teeth of the rotating annular gear, Zf is the number of teeth of the fixed annular gear, and Np is the number of planetary gears.

Abstract: A planetary gearbox including a first sun gear; a first ring gear; a first set of planet gears meshing with the first sun gear and the first ring gear; a second sun gear; a second ring gear; a second plurality of planet gears meshing with the second ring gear and the second sun gear, wherein the ith gear in the first set of planet gears is fixed to the ith gear in the second set of planet gears so that the gears in the first set and the second set rotate together coaxially. The resulting planetary gearbox can be readily integrated into compact robotic joints. Its few lightweight components can be manufactured with high accuracy with standard machining techniques.

Abstract: A method for producing a ring gear for a planetary gear train, wherein a continuous profile is produced by an extrusion process and the continuous profile is subsequently cut to a predetermined cutting length in order to form a ring gear body.

Abstract: An epicyclic gearbox with an integral arrangement of meshing gear elements, including an annulus gear, planet gears, and sun gears, to transfer power from a motive power source to a driven element with a range of applications is provided. The annulus gear, in contact with the power source, forms an exterior gearbox input and is in meshing contact with a number of stepped planet gears supported on floating planet carriers. Each stepped planet gear is positioned internally of the annulus gear and includes two planet stages in meshing contact with corresponding sun gear stages. One of the sun gear stages is an interior gearbox output and transfers power to a machine or device to be driven. Meshing surfaces of the gear elements support helical teeth or spur teeth, with numbers of teeth on meshing gear elements selected for optimal torque transfer from the exterior input to the interior output.

Abstract: An actuator includes: a fixed internal gear that is formed in an annular shape, has a tooth on an inner peripheral surface thereof, and is non-rotatably provided; a movable internal gear that is formed in an annular shape, has a tooth on an inner peripheral surface thereof, and is rotatably provided coaxially with the fixed internal gear; a plurality of external gears that mesh with the fixed internal gear and the movable internal gear, and rotate along an inner peripheral surface of the fixed internal gear; and a carrier that is formed in an annular shape, rotatably supports the external gears, has a tooth for receiving a turning force from a drive motor on an outer peripheral surface thereof, transmits a turning force from the drive motor to the external gears, and is rotatably provided coaxially with the movable internal gear.

Abstract: A rotary geared actuator, having an input gear, an output gear, a plurality of pinions) arranged in an annular configuration about a central axis (A), each pinion including an input gear element and an output gear element, the input gear element meshingly engaged with the input gear and the output gear element meshingly engaged with the output gear, a static ring gear arranged radially outwardly of the pinions and meshingly engaged with the input gear elements of the pinions, a first support ring gear arranged radially inwardly of the pinions and meshingly engaged with the input gear element, and a second support ring gear arranged radially inwardly of the pinions and meshingly engaged with the output gear element.

Abstract: Driving modules, motion assistance apparatuses including at least one of the driving modules, and methods of controlling at least one of the motion assistance apparatus may be provided. For example, a driving module including a driving source on one side of a user and configured to transmit power, an input side rotary body connected to the driving source and configured to rotate, and a first decelerator and a second decelerator configured to operate using the power received from the driving source through the input side rotary body, wherein a gear ratio from the input side rotary body to an output terminal of the first decelerator differs from a gear ratio from the input side rotary body to an output terminal of the second decelerator, may be provided.

Abstract: A scissor drive includes two legs which can be pivoted relative to one another about a pivot axis, each having a longitudinal axis and designed to be connected to an external component, and a motor/gear assembly that drives the relative pivoting movement of the two legs. The first leg includes a housing that is hollow at least in portions, a cavity defined in the hollow housing extending at least in portions along the longitudinal axis of the first leg, and the motor/gear assembly being received in the housing of the first leg at least in portions in the portion of the cavity that extends along the longitudinal axis of the first leg.

Abstract: This variable electric motor system comprises an electrically powered device and a planet gear transmission device. One of a sun gear shaft, a planet gear carrier shaft, and an internal gear carrier shaft of the planet gear transmission device constitutes an output shaft, another shaft constitutes a constant-speed input shaft, and the other shaft constitutes a variable-speed input shaft. The electrically powered device includes: a constant-speed electric motor including a constant-speed rotor that rotates about the axis, and that is connected to the constant-speed input shaft; and a variable-speed electric motor including a variable-speed rotor that rotates about the axis, and that is connected to the variable-speed input shaft. The variable-speed rotor has a shaft insertion hole formed therethrough in the axial direction, the shaft insertion hole having a cylindrical shape centered on the axis. The constant-speed rotor is inserted through the shaft insertion hole.

Abstract: This variable electric motor system comprises an electrically powered device and a planet gear transmission device. One of a sun gear shaft, a planet gear carrier shaft, and an internal gear carrier shaft of the planet gear transmission device constitutes an output shaft, another shaft constitutes a constant-speed input shaft, and the other shaft constitutes a variable-speed input shaft. The electrically powered device includes: a constant-speed electric motor including a constant-speed rotor that rotates about the axis, and that is connected to the constant-speed input shaft; and a variable-speed electric motor including a variable-speed rotor that rotates about the axis, and that is connected to the variable-speed input shaft. The variable-speed rotor has a shaft insertion hole formed therethrough in the axial direction, the shaft insertion hole having a cylindrical shape centered on the axis. The constant-speed rotor is inserted through the shaft insertion hole.

Abstract: This variable electric motor system comprises an electrically powered device and a planet gear transmission device. One of a sun gear shaft, a planet gear carrier shaft, and an internal gear carrier shaft of the planet gear transmission device constitutes an output shaft, another shaft constitutes a constant-speed input shaft, and the other shaft constitutes a variable-speed input shaft. The electrically powered device includes: a constant-speed electric motor including a constant-speed rotor that rotates about the axis, and that is connected to the constant-speed input shaft; and a variable-speed electric motor including a variable-speed rotor that rotates about the axis, and that is connected to the variable-speed input shaft. The variable-speed rotor has a shaft insertion hole formed therethrough in the axial direction, the shaft insertion hole having a cylindrical shape centered on the axis. The constant-speed rotor is inserted through the shaft insertion hole.

Abstract: Provided are gearboxes including compound planet gear assemblies as well as methods of using such gearboxes. A gearbox includes at least a first ring gear and a second ring gear. Depending on the current gear selection, one of these ring gears may be engaged with a shifting mechanism or not engaged with any ring gears when in a neutral gear. The first ring gear may be constantly engaged with a first planet gear of a compound planet gear assembly, while the second ring gear may be constantly engaged with a second planet gear of the same compound planet gear assembly. The first planet gear may be also engaged with a sun gear coupled to a shaft. Another shaft is coupled to the shifting mechanism. Different gear selections of the gearbox engage different ring gears to the shifting mechanism thereby changing the rotational speed ratio of the two shafts.

Abstract: A planetary gear box assembly includes a plastic gear box housing and a first and a second monolithic housing part. The first-stage and second-stage housing parts each have an end face on one axial end of the housing part, and a surrounding wall. A first-stage ring gear is formed inside the surrounding wall of the first-stage housing part, and a second-stage ring gear is formed inside the surrounding wall of the second-stage housing part. The planetary gear box assembly has a planetary gear carrier with a generally cylindrical carrier body with a cylinder wall and a window extending through the cylinder wall. The window is axially adjoined by a first and a first radial pocket. The first and first radial pockets are radial indentations in a radially outer surface of the cylinder wall and accommodate planetary shaft ends of planetary gears.

Abstract: A wireless communication method embeds service related information, including a version of a service associated with the service related information, within an initial wireless access message. The method may also include broadcasting the initial wireless access message including the embedded service related information. Another aspect of the present disclosure includes a wireless communication method that indentifies service related information embedded within an initial wireless access message. The method may also establish a connection with an access node of the wireless communication network to receive a service when a version of a service associated with the service related information satisfies a predetermined condition.

Abstract: A gear transmission system (20) comprising at least a first cylindrical gear (21) and a second cylindrical gear (22). Each of the first and the second cylindrical gears (21, 22) comprise a plurality of teeth (23, 26). The teeth (23) of the first cylindrical gear (21) having a first tooth flank (24) for contacting a first tooth flank (27) of the teeth (26) of the second cylindrical gear (22) according to a predefined first contact line (30). The first tooth flanks (24, 27) of the teeth (23, 26) of each of the first and second cylindrical gears (21, 22) have a tooth shape and tooth properties determined by the predefined first contact line (30).

Abstract: A method for manufacturing a carrier assembly of a stacked planetary gear set is provided. The method includes forming the inner and outer spiders and attaching the spiders to a back plate or to each other to form the carrier assembly. One or both of the inner and outer carrier spiders are formed from powdered metal, by precision casting, and/or by stamping. The stacked planetary gear set may be axially aligned or axially offset.

Abstract: A high ratio epicyclic gear train (A) with improved load carrying capability for transmitting power from a driven input shaft, such as may be driven by a turbine engine or engines, to a output shaft, as may be coupled to a rotor of a rotary wing aircraft. The compound epicyclic gear train incorporates a load sharing mechanism consisting of a drive sun gear (10), an idler sun gear (11), a ring gear (12), a set of drive planet gear assemblies (13), a set of idler planet gear assemblies (14), and a planet carrier assembly (15) coupled to provide at least two power pathways through said epicyclic gear train (A) between said driven input shaft and said output shaft to provide an improved overall power density of the transmission.

Abstract: A planetary gearbox, also known as an epicyclical gearbox is disclosed herein. The gearbox includes multiple rows of planets and a ring gear. The sun gear is a single unitary structure which simultaneously engages the multiple rows of planets. The system lowers the stress level on torque generating devices incorporating such a gearbox.

Abstract: A sun gear member, planetary gear members, a first ring gear member, and a second ring gear member together form a paradox gear mechanism. A clutch mechanism is disposed between an input gear member and the first ring gear member. The clutch mechanism rotates the first ring gear member, when the input gear member rotates. The clutch mechanism disconnects transmission of the power to the input gear member when the first ring gear member rotates. The sun gear member and the first ring gear member are individual input elements. When one of the sun gear member and the first ring gear member exclusively rotates, the second ring gear member rotates in accordance with the rotation. The sun gear transmits power more reliably without increasing manufacturing cost and without thwarting downsizing of the product.

Abstract: An automatic transmission for an electric vehicle hub includes an external motor rotor fixedly connected with a motor shaft; a sun gear; at least three first planet gears; and at least three second planet gears coaxially fixed with the corresponding first planet gears and which are engaged with the sun gear. The first and the second planet gears are respectively engaged with first and second internal gears, and the second internal gear has a diameter greater than that of the first internal gear. The rotating disk is arranged between the first internal gear and the second internal gear, and a hub is fixed to exterior of the rotating disk. The automatic transmission further includes a clutch device, making the rotating disk and the first internal gear contact with each other for a transmission of slower rpm, and when the rpm reaches critical, at a high-speed rotation.

Abstract: A planetary gear device having two sun gears with different diameters that engage with double planet gears having a first gear teeth area, which interacts with the fist sun gear, and a second gear teeth area, which interacts with the second sun gear. The double planet gears are continuous helical gear wheels. The crown circle diameters of the gear teeth areas of the double planet gears and the crown circle diameters of the sun gears are adapted such that the pitch circle diameters between the double planet gears and the sun gears are arranged in the center between the crown circle diameters and the effective root diameters of the gear teeth areas of the double planet gears and the sun gears.

Abstract: A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

Abstract: An arrangement in a planetary gearing includes a rotatable shaft connected to the planet wheel carrier of planet wheels, an internal gear and a sun wheel, wherein the planet wheels operatively engage by their coggings, i.e. mesh, with the outermost fixed-position cogging of the internal gear and with the centrally located cogging of the sun wheel. The power is transmitted from the sun wheel to the input shaft of the following stage by a coupling permitting radial and/or angular deflection. The lubrication system includes a connection permitting rotation and deflection between the frame and the planet wheel carrier.

Abstract: An epicyclic gearbox includes a shell, a sun gear assembly and a planet gear assembly. The shell is in the form of a drum formed with plain teeth on an internal side. The sun gear assembly for operative connection to a motor, the sun gear assembly includes a sun gear formed with bevel teeth. The planet gear assembly includes a spider for operative connection to a passive device. The planet gears are supported on the spider. Each planet gear includes plain teeth for engagement with the plain teeth of the shell and bevel teeth for engagement with the bevel teeth of the sun gear.

Abstract: The transmission comprises a sun gear fixed to an input shaft, four pinions, and a carrier part connected to an output shaft. Each pinion has a planetary gear engaged with the sun gear, and planetary gears having the number of teeth different from that of that planetary gear. Each internal gear engaged with these planetary gears can perform a independent rotating motion by the rotation of the input shaft. The braking force is selectively applied to the rotating motion of each internal gear by pressing breaking part by the actuator in selecting a gear for gearshift. Here, the braking force is gradually increased to stop the rotating motion. As a result, the a power interrupter becomes unnecessary and the miniaturization of the transmission can be attained.

Abstract: A gear mechanism having extremely less backlash, capable of suppressing the rattling noise of gears, having a large loading resistance in the thrust direction, and capable of transmitting high torque by using the gears transmitting a force by the meshing of the gears with each other in place of the transmission of the force by friction. The gear mechanism is formed by disposing the plurality of spur gears in the meshed state with each other. The screw-like gears (2) and (4) are disposed on the same axis as the spur gears (1) and (3) in the meshed state with each other. The screw-like gears (2) and (4) adjacent to each other are formed in screw shapes having lead angles extending in the reverse directions to each other and equal in angle to each other. The spur gear (1) and the screw-like gear (2) are rotated integrally with each other to transmit its rotation to the spur gear (3) and the screw-like gear (4) adjacent to each other.

Abstract: This planetary roller driving device includes: a planetary roller speed up gear having a first carrier being a first input axis and a first sun roller being a first output axis; a planetary roller reduction gear having a second sun roller being a second input axis and a second carrier being a second output axis, the second input axis being joined with the first output axis; a roller ring driving mechanism; a housing which accommodates the planetary roller speed up gear, the planetary roller reduction gear, and the roller ring driving mechanism; a roller ring rotation control circuit which controls a rotation of the roller ring driving mechanism corresponding to an external environmental condition; and a torque-assisting mechanism which is provided in the housing and provides an assisting torque to the first input axis or the second output axis.

Abstract: The present invention relates to automatic transmissions and gear trains. In particular, the instant invention relates to an automatic transmission gear train with improved resistance to deterioration with an increased effective life. The gear train of the instant invention comprises eight pinion gears assembled into one carrier utilizing a forward and a rear sun gear, a ring gear, a band drum and a one way roller clutch.

Abstract: A planetary gear train having planetary gears (8) which are rotatably mounted on a planet carrier (18) and are in toothed contact with an internally toothed ring gear (14) and a sun gear (4). For a simplified, process-safe and inexpensive backlash of the planetary gears (8) without axial displacement of the sun gear (4), the ring gear (14) and the planetary gears (8) are conically designed so that planetary gear axles (16) are retained in the planetary gear carrier (18) at an inclined angle (a) and that the planetary gears (8) are axially movably disposed upon and coordinated with the planetary gear axles (16) and the position of the planetary gears (8) can be adjusted within the planetary train by adjusting mechanisms for adjusting a backlash.

Abstract: A first rotary member rotates with a crankshaft and has a first gear. A second rotary member rotates with a camshaft and has a second gear that is axially shifted from the first gear. A planetary rotary member has third and fourth gears, which are eccentrically meshed respectively with the first and second gears to perform a planetary motion. A biasing member is interposed between the planetary rotary member and a planetary carrier, which supports the planetary rotary member. The planetary rotary member is in contact with the biasing member at a contact portion having an axial center. The axial center is located on a radially inner side of a meshed portion between the second and fourth gears, which has a backlash larger than that of a meshed portion between the first and third gears.

Abstract: A planetary gear device having two sun gears with different diameters that engage with double planet gears having a first gear teeth area, which interacts with the fist sun gear, and a second gear teeth area, which interacts with the second sun gear. The double planet gears are continuous helical gear wheels. The crown circle diameters of the gear teeth areas of the double planet gears and the crown circle diameters of the sun gears are adapted such that the pitch circle diameters between the double planet gears and the sun gears are arranged in the center between the crown circle diameters and the effective root diameters of the gear teeth areas of the double planet gears and the sun gears.

Abstract: There is provided a built-in type index table in which a power transmitting means scarcely has backlash and, at the same time, the space and cost can be saved. The index table includes a rotary table for setting a workpiece for a machine tool; a rotary table shaft fixedly provided on the rotary table; a driving motor mechanism, which is a driving source; and a planetary roller speed-reduction mechanism having a sun roller, which is a motor output shaft of the driving motor mechanism, a ring fixed to the speed-reduction mechanism, a plurality of planetary rollers arranged at equal angular intervals between the sun roller and the ring in a pressurized state, and a planetary roller harness that fixedly supports a plurality of planetary roller shafts pivotally supporting the planetary rollers in a rotatable manner and is fixedly provided coaxially with the rotary table shaft.

Abstract: An automatic transmission assembly is constructed or modified to minimize effects of wear thereon and maximize its operational life. The assembly includes a transmission case and has a modified ring-shaped center support that is to be secured against rotation within the transmission case. A center support plate, which is attachable to and detachable from the ring-shaped center support, includes protrusions thereon that engage between cooperating protrusions defined on the transmission case to secure the ring-shaped center support against rotation within the transmission case. The invention is particularly useful when the modified ring-shaped center support is a worn, original equipment support that has deteriorated in function. A process of modifying an automatic transmission assembly is also described.

Abstract: In a vehicle, having a fixed supporting structure and a load movable relative thereto, a jam tolerant actuating system, a method for controlling this system including: Locating a physical coupling/decoupling mechanism between the load and an actuator assembly as close a practicable to the load; constructing the coupling/uncoupling mechanism to be reversible, and hence testable; and controlling the connection/disconnection via decision making electronics which will detect any system failure by monitoring, at a minimum: actuator main motor load and speed, and actuator output load. Also set forth are specific embodiments of pivotable rotary geared actuators as well as linear ball screw type actuators embodying the coupling/uncoupling mechanisms of this invention.

Abstract: A method is provided for manufacturing a compound helically toothed planet gear for a planetary gear set wherein the individual gear elements of the compound planet gear have different leads. The method identifies and utilizes the several factors affecting gear timing for compound helical planet gears having different leads to provide planet gears capable of attaining equal load share among the several gears of the planetary gear set. Specifically, the method of the present invention utilizes a mounting shoulder and bore axis to provide common locating features for use throughout the manufacturing process The method further provides for bore honing and removal of equal amounts of material from both sides of each gear tooth in the gear finishing process so as not to alter gear timing between the compound gear elements.

Abstract: A gearset assembly includes a pinion carrier containing first, second and third long pinions pinion mutually spaced angularly about an axis, and supported for rotation on the carrier, and three pairs of short pinions, each supported for rotation on the carrier, the pinions of the first pair meshing with the first long pinion, the pinions of the second pair meshing with the second long pinion, and the pinions of the third pair meshing with the third long pinion.

Abstract: A high ratio, double helical epicyclic gear transmission that is primarily intended for use in rotary wing aircraft employs double helical planet gears to obtain a reduction in size of the transmission, to improve the safety of the transmission, and to reduce the noise created by operation of the transmission.

Abstract: A first planetary gear unit is arranged to convert an input rotation from an input shaft to an output rotation whose speed is lower than that of the input rotation. A first unit including second and third planetary gear units is arranged between the first planetary gear unit and the output shaft. The first unit manages the first planetary gear unit's output rotation and provides the output shaft with seven types of rotation which correspond to 6-forward speed and one reverse positions. A second unit is arranged between the first planetary gear unit and the first unit to manage a power transmission therebetween. One of the second and third planetary gear units is of a double ring type, each being meshed with the sun gear and inside and outside ring gears, and a pinion carrier carrying the pinions. The pinion carrier is connected to the output shaft to rotate therewith.

Abstract: A compound differential planetary gear assembly (50) includes a sun gear (52), a plurality of planet gears (53) engaging the sun gear, a plurality of first ring gears (54), and a plurality of second ring gears (55). Each of the second ring gears has a number of teeth that is different from the number of teeth of the first ring gears. The first and second ring gears are arranged alternately in an axial stack. Each planet gear has a constant gear-tooth cross-section along the length of the stack, with its gear teeth in meshing engagement with the teeth of the first and second ring gears. Loads transmitted between the first and second ring gears and the planets act in alternate directions along the length of the stack.

Abstract: A compound differential planetary gear assembly (50) includes a sun gear (52), a plurality of planet gears (53) engaging the sun gear, a plurality of first ring gears (54), and a plurality of second ring gears (55). Each of the second ring gears has a number of teeth that is different from the number of teeth of the first ring gears. The first and second ring gears are arranged alternately in an axial stack. Each planet gear has a constant gear-tooth cross-section along the length of the stack, with its gear teeth in meshing engagement with the teeth of the first and second ring gears. Loads transmitted between the first and second ring gears and the planets act in alternate directions along the length of the stack.