Sundstrand Corporation

Jeffrey D Baldwin

Bernard A Raad

Clarence F Dolan

Jude C Lai

Larry M McCulloh

Ellen J Wagle

An offset gearbox of an aircraft has a sump for a lubricant. A heat exchanger core extends through the sump in contact with the lubricant. A fluid coolant for cooling an accessory such as an electrical power generating unit drivingly connected to the offset gearbox is circulated through the core in thermal communication but not mixed with the lubricant of the offset gearbox for cooling the lubricant. The cooling arrangement for the offset gearbox advantageously does not require a separate or dedicated heat exchanger which reduces system weight and cost. The single pump of the accessory can also be used for circulating the coolant. Increased reliability, independent oil change for maintenance and enhanced attitude performance are attained as gearbox performance does not affect power generating unit performance, and visa versa. An existing aircraft can be modified to include the offset gearbox with a minimum of modification and little additional weight and plumbing.

Cooling arrangement and method for offset gearbox

An electrical machine (100) retained within a housing (116) in accordance with the invention includes a stator having a plurality of laminations (136) which are axially joined together to define a stator core (104) having a plurality of slots (106) which retain electrical windings (112) disposed circumferentially around the stator core which define poles; a first and second retaining mechanism (120) attached to the housing and having a radial projection extending radially inward from an inner cylindrical surface (118) of the housing with the retaining mechanisms having at least one axially projecting retainer (130) extending axially from a surface (132) of the radial projection (126, 128) facing a first or second axial end of the stator core and engaging the first and second axial end of the stator core.

Stator retention mechanism

A starting system for starting a prime mover connected to a generator by a torque link includes an induction motor having a torque rating substantially equal to the minimum torque required to rotate the rotor of the generator from rest to a particular speed within a predetermined time period while the torque link is deactuated, a source of electrical power, contactors for connecting the source of electrical power to the induction motor when the torque link is deactuated to accelerate the generator rotor to the particular speed, a second set of contactors for connecting the source of electrical power to the generator windings once the generator rotor has reached a particular speed to cause the generator to operate as a synchronous motor and a torque link actuator for actuating the torque link once the generators operating as a synchronous motor to bring the prime mover up to starting speed. The usual large magnitude transient developed in the source of electrical power is thus broken down into three transients of lesser magnitude.

Prime mover starting system and method

A rotary electric machine including a stator with a rotor journalled for rotation within the stator about an axis and carrying an electrical conductor. The resistor is mounted on the rotor and is electrically associated with the conductor. The resistor is narrow axially of the rotor and elongated radially but within the periphery of the rotor to thereby provide an axially compact rotary electric machine.

Compact resistor assembly for rotary electric machine

An axially and radially compact rectifier assembly for installation in alternator rotors includes two spaced plates, each mounting diodes which extend axially toward the opposite plate, on which they are not mounted. The axial extension of the diodes provides for radial compactness. The diodes on each plate are staggered with respect to the diodes on the other plate so that they may nest between one another, to provide axial compactness as well.

Growing community of inventors

Rockford, IL, United States of America

Jeffrey D Baldwin