A torque motor has a mechanical reference member, an armature, and a field assembly. The field assembly includes field pole pieces defining a pole opening, and the armature is mounted to the mechanical reference member for rotation about a motor axis and extends into the pole opening with respective gaps to the field pole pieces. The field assembly is secured to the mechanical reference member and spaced therefrom by elastically deformable flexures, deformed sufficiently to locate the armature at a predetermined position within the pole openings with corresponding lengths of the gaps. During manufacture, a load can be applied to move the field assembly relative to the mechanical reference member against the deformation force of the flexures to locate the pole opening relative to the armature pole piece such that the gaps of desired lengths are formed.
A torque motor has a mechanical reference member, an armature, and a field assembly. The field assembly includes field pole pieces defining a pole opening, and the armature is mounted to the mechanical reference member for rotation about a motor axis and extends into the pole opening with respective gaps to the field pole pieces. The field assembly is secured to the mechanical reference member and spaced therefrom by elastically deformable flexures, deformed sufficiently to locate the armature at a predetermined position within the pole openings with corresponding lengths of the gaps. During manufacture, a load can be applied to move the field assembly relative to the mechanical reference member against the deformation force of the flexures to locate the pole opening relative to the armature pole piece such that the gaps of desired lengths are formed.
H02K 7/00 - Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
H02K 15/00 - Processes or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines
H02K 26/00 - Machines adapted to function as torque motors, i.e. to exert a torque when stalled
A thrust reverser actuation system for a jet engine having a turbine engine surrounded by a nacelle to define an annular air flow path between the turbine engine and the nacelle, with a thrust reverser having a movable element to reverse the direction of at least a portion of the air flow along the air flow path, where the thrust reverser actuation system includes a hydraulic actuator configured to be operably coupled to the movable element, and a remote actuator that controls the inhibit function of the hydraulic system.
F02K 1/70 - Reversing fan flow using thrust reverser flaps or doors mounted on the fan housing
F02K 1/72 - Reversing fan flow using thrust reverser flaps or doors mounted on the fan housing the aft end of the fan housing being movable to uncover openings in the fan housing for the reversed flow
F02K 1/76 - Control or regulation of thrust reversers
F02K 3/06 - Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber the plant including ducted fans, i.e. fans with high volume, low-pressure outputs, for augmenting jet thrust, e.g. of double-flow type with front fan
In some aspects, an aircraft engine thrust reverser lock system includes a pin-capturing member. The pin-capturing member includes a body that is rotatable about an axis defined by a pivot extending through the body. The body includes an interior surface that defines a slot. The slot has an opening that is sized to receive a pin into the slot. One side of the slot includes a protruded sidewall surface that protrudes into the slot toward an another sidewall surface of the slot. The protruded sidewall surface defines an apex between the open and closed ends of the slot. Between the apex and the closed end of the slot, the protruded sidewall surface faces the rotational axis.
An apparatus includes a housing which defines a longitudinal axis; a positioning element which, relative to the housing, translates linearly along the longitudinal axis; and a rotational member which, relative to the housing, rotates about the longitudinal axis as the positioning element translates linearly along the longitudinal axis. The rotational member defines a helix to receive torque from the positioning element as the positioning element translates linearly along the longitudinal axis. The apparatus further includes a first sensor assembly to detect minor angular displacement of the rotational member (e.g., less than 360 degrees). The apparatus further includes a second sensor assembly to detect major angular displacement of the rotational member (e.g., a number of full 360 degree rotations). Such detection is capable of identifying a full angular displacement of the rotational member in response to linear translation of the positioning element from an initial position to a sensed position.
G01B 7/14 - Measuring arrangements characterised by the use of electric or magnetic techniques for measuring distance or clearance between spaced objects or spaced apertures
H02K 7/06 - Means for converting reciprocating motion into rotary motion or vice versa
G01D 5/14 - Mechanical means for transferring the output of a sensing memberMeans for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for convertingTransducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
G01B 7/00 - Measuring arrangements characterised by the use of electric or magnetic techniques
An aircraft engine thrust reverser lock system (100) includes a pin- capturing member (102). The pin-capturing member includes a body that is rotatable about an axis defined by a pivot (104) extending through the body. The body includes an interior surface that defines a slot (150). The slot has an opening that is sized to receive a pin (110) into the slot. One side of the slot includes a protruded sidewall surface that protrudes into the slot toward an another sidewall surface of the slot. The protruded sidewall surface defines an apex (206) between the open and closed ends of the slot. Between the apex and the closed end of the slot, the protruded sidewall surface faces the rotational axis.
An aircraft engine thrust reverser lock system (100) includes a pin- capturing member (102). The pin-capturing member includes a body that is rotatable about an axis defined by a pivot (104) extending through the body. The body includes an interior surface that defines a slot (150). The slot has an opening that is sized to receive a pin (110) into the slot. One side of the slot includes a protruded sidewall surface that protrudes into the slot toward an another sidewall surface of the slot. The protruded sidewall surface defines an apex (206) between the open and closed ends of the slot. Between the apex and the closed end of the slot, the protruded sidewall surface faces the rotational axis.
In some aspects, an aircraft engine thrust reverser lock system includes a pin-capturing member. The pin-capturing member includes a body that is rotatable about an axis defined by a pivot extending through the body. The body includes an interior surface that defines a slot. The slot has an opening that is sized to receive a pin into the slot. One side of the slot includes a protruded sidewall surface that protrudes into the slot toward an another sidewall surface of the slot. The protruded sidewall surface defines an apex between the open and closed ends of the slot. Between the apex and the closed end of the slot, the protruded sidewall surface faces the rotational axis.
A method of locking a linear output member in a retracted position within a linear actuator, where the linear output member is capable of axial motion within a housing of the linear actuator, includes rotating a generally tubular rotor disposed within a rotary lock assembly of the actuator to a first rotor position, and shifting a lock capable of radial displacement within the rotary lock assembly based on rotating the rotor to the first position. The lock engages a radial groove of the linear output member when the linear output member is in a retracted position. The rotary lock assembly is constrained from axial motion. The radial groove of the linear output member includes an axially angled, substantially planar surface. The lock is configured to include an axially angled surface shaped complimentary to the axially angled, substantially planar surface of the radial groove.
A thrust reverser actuation system for a jet engine having a turbine engine surrounded by a nacelle to define an annular air flow path between the turbine engine and the nacelle, with a thrust reverser having a movable element to reverse the direction of at least a portion of the air flow along the air flow path, where the thrust reverser actuation system includes a hydraulic actuator configured to be operably coupled to the movable element, and a remote actuator that controls the inhibit function of the hydraulic system.
A thrust reverser actuation system for a jet engine having a turbine engine surrounded by a nacelle to define an annular air flow path between the turbine engine and the nacelle, with a thrust reverser having a movable element to reverse the direction of at least a portion of the air flow along the air flow path, where the thrust reverser actuation system includes a hydraulic actuator configured to be operably coupled to the movable element, and a remote actuator that controls the inhibit function of the hydraulic system.
F02K 1/70 - Reversing fan flow using thrust reverser flaps or doors mounted on the fan housing
F02K 1/72 - Reversing fan flow using thrust reverser flaps or doors mounted on the fan housing the aft end of the fan housing being movable to uncover openings in the fan housing for the reversed flow
F02K 1/76 - Control or regulation of thrust reversers
F02K 3/06 - Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber the plant including ducted fans, i.e. fans with high volume, low-pressure outputs, for augmenting jet thrust, e.g. of double-flow type with front fan
An automatically locking actuator includes a first end connector, a rotatable drive screw operably coupled to the first end connector, a nut assembly threadably mounted on the drive screw, a second end connector operably coupled to the nut assembly and a rotary lock having a rotor and where the actuator moves between extended and retracted positions in response to rotation of the rotor.
F16H 3/06 - Toothed gearings for conveying rotary motion with variable gear ratio or for reversing rotary motion without gears having orbital motion with worm and worm-wheel or gears essentially having helical or herring-bone teeth
F16H 27/02 - Step-by-step mechanisms without freewheel members, e.g. Geneva drives with at least one reciprocating or oscillating transmission member
F16H 29/02 - Gearings for conveying rotary motion with intermittently-driving members, e.g. with freewheel action between one of the shafts and an oscillating or reciprocating intermediate member, not rotating with either of the shafts
F16H 29/20 - Gearings for conveying rotary motion with intermittently-driving members, e.g. with freewheel action the intermittently-acting members being shaped as worms, screws, or racks
A linear actuator is disclosed. The linear actuator includes a housing, a linear output member, and a rotary lock assembly. The linear output member includes a radial groove and is axially movable from a retracted position within the housing. The rotary lock assembly is constrained from axial motion within the housing and includes a rotor and a lock. The rotor is capable of rotation from a first to a second position. When the linear output member is in the retracted position, the rotor surrounds the radial groove. When the rotor rotates to the first position, the lock engages the radial groove and prevents axial motion of the output member from the retracted position.
F16H 37/06 - Combinations of mechanical gearings, not provided for in groups comprising essentially only toothed or friction gearings with a plurality of driving or driven shaftsCombinations of mechanical gearings, not provided for in groups comprising essentially only toothed or friction gearings with arrangements for dividing torque between two or more intermediate shafts
F16H 3/06 - Toothed gearings for conveying rotary motion with variable gear ratio or for reversing rotary motion without gears having orbital motion with worm and worm-wheel or gears essentially having helical or herring-bone teeth
F16H 27/02 - Step-by-step mechanisms without freewheel members, e.g. Geneva drives with at least one reciprocating or oscillating transmission member
F16H 29/02 - Gearings for conveying rotary motion with intermittently-driving members, e.g. with freewheel action between one of the shafts and an oscillating or reciprocating intermediate member, not rotating with either of the shafts
F16H 29/20 - Gearings for conveying rotary motion with intermittently-driving members, e.g. with freewheel action the intermittently-acting members being shaped as worms, screws, or racks
14.
System and method for operating a thrust reverser for a turbofan propulsion system
A thrust reverser assembly for use in a turbofan engine assembly. The engine assembly includes a core gas turbine engine and a core cowl which circumscribes the core gas turbine engine. A nacelle is positioned radially outward from the core cowl to define a fan nozzle duct between the core cowl and a portion of the nacelle. The nacelle includes a stationary cowl. The thrust reverser assembly includes a first translating cowl that is slidably coupled to the nacelle. The first translating cowl is positionable with respect to the stationary cowl. A second translating cowl is slidably coupled to the nacelle such that the first translating cowl is positioned between the stationary cowl and the second translating cowl. The second translating cowl is positionable with respect to the first translating cowl. A positioning assembly is coupled to the first translating cowl. An actuator assembly is operatively coupled to the second translating cowl for selectively moving the second translating cowl. The actuator assembly is configured to engage the positioning assembly to selectively move the first translating cowl.
F02K 3/02 - Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber
F02K 1/72 - Reversing fan flow using thrust reverser flaps or doors mounted on the fan housing the aft end of the fan housing being movable to uncover openings in the fan housing for the reversed flow
F02K 1/76 - Control or regulation of thrust reversers
15.
Direct drive servovalve having redundant drive motors
A direct drive servovalve (10) includes redundant drive motors (14) coupled to a common valve drive shaft (22,24) by a connection device (26). The connection device (26) is configured to allow operation of the servovalve (10) in the case where one or more of the drive motors (14) becomes inoperable, such as caused by jamming or binding of a rotor associated with the drive motor. By use of the connection device (26), in the event that one of the drive motors (14) was to become jammed, the remaining operable motors (14) can continue to stroke or cause translation of a valve member (18) of the direct drive servovalve (10) to allow its continued operation.
A shift lock assembly includes a drive member carried by a drive shaft and configured to rotatably couple to a drive motor and a shift mechanism disposed between the drive member and a ground plate, the shift mechanism configured to move between a first position and a second position relative to the drive member and the ground plate. When disposed in the first position, the shift mechanism is configured to couple the drive shaft to the ground plate and decouple the drive shaft from the drive member to allow rotation of the drive member relative to the drive shaft. When disposed in the second position, the shift mechanism is configured to couple the drive shaft to the drive member and decouple the drive shaft from the ground plate to allow rotation of the drive shaft in response to rotation of the drive member.
A floating piston actuator for use with multiple hydraulic systems includes a housing and a piston assembly. The piston assembly includes an elongate shaft or ram, a secured piston coupled to the ram, and a set of moveable pistons moveably disposed within the housing chamber on the ram such that the set of moveable pistons are translatable relative to a longitudinal axis of the ram. The set of moveable pistons form at least three hydraulically separate actuator cylinders where each of the three hydraulically separate actuator cylinders are disposed in fluid communication with a corresponding pressurized fluid source. The floating piston actuator allows hydraulic redundancy while maintaining a similar length compared to existing multi-system actuators. The floating pistons can be arranged in multiple configurations to allow operation with a hydraulic system failure without force fight or binding and with a higher output force than conventional multi-system actuators.
F15B 15/14 - Fluid-actuated devices for displacing a member from one position to anotherGearing associated therewith characterised by the construction of the motor unit of the straight-cylinder type
A servovalve torque motor includes first and second pole pieces and an armature. Each of the first and second pole pieces includes an armature face that opposes the armature. The area of the armature face of the second pole piece is smaller than the area of the armature face of the first pole piece. The unequal areas of the first and second armature faces create a bias in the servovalve torque motor while allowing the first and second pole pieces to be disposed at equal distances from the armature to define substantially equal air gaps. The inclusion of substantially equal air gaps between the pole pieces and the armature reduces the maximum flux in the armature for the same bias and torque output, compared to conventional servovalve torque motors. The reduction in maximum armature flux decreases armature saturation and improves linearity during operation.
F15B 13/043 - Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure with electrically-controlled pilot valves
19.
CONTROLLER FOR ACTUATION SYSTEM EMPLOYING KALMAN ESTIMATOR INCORPORATING EFFECT OF SYSTEM STRUCTURAL STIFFNESS
A controller (14) for an electro-mechanical actuation system such as a missile fin (12) actuator includes a Kalman estimator circuit (40) which generates an estimate of operating state including position and velocity of motor (16), position and velocity of a position-controlled element (PCE) (10), and motor current. The estimate is generated based on a dynamic model explicitly including the effect of structural stiffness and damping in the coupling between the motor (16) and the PCE (10), for example by treating it as a mechanical oscillator having spring and damping constants. The Kalman estimator (40) operates on a motor drive control signal and a measured position signal which may be from a Hall sensor sensing motor position. A linear quadratic regulator circuit (42) generates a control effort signal by applying a state feedback gain matrix to a state vector. The state feedback gain matrix minimizes a quadratic cost function representing variance of the control effort signal and/or the measured position signal.
G05B 13/04 - Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators
20.
Controller for actuation system employing Kalman estimator incorporating effect of system structural stiffness
A controller for an electro-mechanical actuation system (e.g., missile fin actuator) includes a Kalman estimator circuit generating an estimate of operating state including position and velocity of motor, position and velocity of a position-controlled element (PCE), and motor current. The estimate is generated based on a dynamic model explicitly including the effect of structural stiffness and damping in the coupling between the motor and PCE, for example by treating it as a mechanical oscillator having spring and damping constants. The Kalman estimator operates on a motor drive control signal and a measured position signal which may be from a Hall sensor sensing motor position. A linear quadratic regulator circuit applies a state feedback gain matrix to a state vector to generate a control effort signal. The state feedback gain matrix minimizes a quadratic cost function representing variance of the control effort signal and/or the measured position signal.
G05B 11/42 - Automatic controllers electric with provision for obtaining particular characteristics, e.g. proportional, integral, differential for obtaining a characteristic which is both proportional and time-dependent, e.g. P. I., P. I. D.
21.
DIRECT DRIVE SERVOVALVE HAVING REDUNDANT DRIVE MOTORS
A direct drive servovalve (10) includes redundant drive motors (14) coupled to a common valve drive shaft (22,24) by a connection device (26). The connection device (26) is configured to allow operation of the servovalve (10) in the case where one or more of the drive motors (14) becomes inoperable, such as caused by jamming or binding of a rotor associated with the drive motor. By use of the connection device (26), in the event that one of the drive motors (14) was to become jammed, the remaining operable motors (14) can continue to stroke or cause translation of a valve member (18) of the direct drive servovalve (10) to allow its continued operation.
A locking device includes a shape memory alloy actuator that engages a locking pin to release the pin and unlock the device it is engaging. Upon heating the shape memory alloy member, it returns to a predetermined shape, which has a length shorter than its non-heated length. As the shape memory alloy actuator shortens, it pulls the locking pin at least a pre-determined distance to release the locking pin from engagement with the device it is locking and into engagement with a pin release member. The pin release member holds the locking pin in the unlocked position until the pin release member is moved from engagement with the locking pin. Once moved, the pin release member disengages from the locking pin and the pin is moved back into its original, locked position. The shape memory alloy actuator and pin release member are also returned to their original position.
A slot cover actuation assembly controls access through a slot on a projectile. The slot cover actuation assembly includes a slot cover, a fastener (e.g., a screw), and an actuator (e.g., a squib device). The fastener is arranged to position the slot cover at an installation position on the projectile. The slot cover covers the slot on the projectile when the slot cover resides at the installation position. The actuator is arranged to release the slot cover from the installation position on the projectile. The slot cover uncovers the slot on the projectile when the actuator releases the slot cover from the installation position on the projectile, thus allowing a control surface member (e.g., a fin) to deploy.
A device has built-in inductive load testing capabilities. The device includes a device housing, an inductive load disposed within the device housing; and test circuitry disposed within the device housing. The test circuitry is constructed and arranged to effectuate application of a modulated test signal to the inductive load, and obtain a result signal in response to the application of the modulated test signal to the inductive load. The test circuitry is further constructed and arranged to generate an output signal indicating that the inductive load is in one of (i) a shorted inductive load state, (ii) a normal inductive load state, and (iii) an abnormally high inductive load state, based on the result signal. Such test circuitry is well-suited for testing a variety of devices having inductors/coils which are susceptible to defects (e.g., a solenoid, a motor winding, various actuator components, etc.).
An actuator system has a external rotor motor (22) having: (i) an internal armature configured as a stator (22) having a set of coils (66) wrapped around a set of arms, and (ii) an external permanent magnet (64) rotor having a set of poles configured to rotate less than 90 degrees around the stator. The actuator system has a drive shaft (26) configured to be rotated by the external rotor motor. The actuator system has a drive train (24) connecting the external permanent magnet rotor (30) to the drive shaft, and configured to provide gear ratio to the drive shaft.
H02K 26/00 - Machines adapted to function as torque motors, i.e. to exert a torque when stalled
F16H 21/44 - Gearings comprising primarily only links or levers, with or without slides all movement being in, or parallel to, a single plane for conveying or interconverting oscillating or reciprocating motions
26.
Limited angle external rotor motor actuator system
The actuator system has a external rotor motor having: (i) an internal armature configured as a stator having a set of coils wrapped around a set of arms, and (ii) an external permanent magnet rotor having a set of poles configured to rotate less than 90 degrees around the stator. The actuator system has a drive shaft configured to be rotated by the external rotor motor. The actuator system has a drive train connecting the external permanent magnet rotor to the drive shaft, and configured to provide gear ratio to the drive shaft.
One embodiment is directed to a locking mechanism. The locking mechanism has a housing and a rotary actuator carried by the housing. The rotary actuator includes a shaft and armature disposed around at least a portion of the shaft. The armature is configured to rotate the shaft about a longitudinal axis of the shaft. The locking mechanism also has a cam carried by the shaft and a set of locking balls disposed between the cam and the housing. The locking mechanism has a locking assembly carried by the housing, the locking assembly being axially positionable between a locked position relative to the housing and a released position relative to the housing.
One embodiment is directed to a locking mechanism. The locking mechanism has a housing and a rotary actuator carried by the housing. The rotary actuator includes a shaft and armature disposed around at least a portion of the shaft. The armature is configured to rotate the shaft about a longitudinal axis of the shaft. The locking mechanism also has a cam carried by the shaft and a set of locking balls disposed between the cam and the housing. The locking mechanism has a locking assembly carried by the housing, the locking assembly being axially positionable between a locked position relative to the housing and a released position relative to the housing.
A position sensing assembly includes a bearing element and a helically shaped rotational member used to drive a portion of a sensor assembly, such as a Digital Rotary Magnetic Encoder. Interaction between the bearing element and a helically shaped rotational member minimizes the presence of backlash in the position sensing assembly. Accordingly, as an actuator assembly drives both a control element, such as a flight control surface, and the position sensing assembly, the sensor assembly generates an output signal that accurately reflects the position of the control element.
G01B 7/30 - Measuring arrangements characterised by the use of electric or magnetic techniques for measuring angles or tapersMeasuring arrangements characterised by the use of electric or magnetic techniques for testing the alignment of axes
G01B 7/14 - Measuring arrangements characterised by the use of electric or magnetic techniques for measuring distance or clearance between spaced objects or spaced apertures
F42B 10/00 - Means for influencing, e.g. improving, the aerodynamic properties of projectiles or missilesArrangements on projectiles or missiles for stabilising, steering, range-reducing, range-increasing or fall-retarding
A valve assembly controller is configured with a table (250) having a set of command signal values representing commanded positions of a valve element (110) to obtain a desired flow rates through a fluid pathway (112). The table also includes a set of empirically measured drive signal values representing the actual positions of the valve element required to obtain the desired flow rates through the fluid pathway. During operation, in order to obtain a desired flow rate through the fluid pathway, the controller intercepts a command signal (107) from a command signal source (102) and provides the valve assembly (106) with a corresponding drive signal (116) based upon the table values. The controller (104) therefore controls the positioning of the valve element such that the valve element is opened to a position either greater or less than the commanded position in order to provide the desired flow through the fluid pathway.
The actuator has a shaft having a starting resistance portion, and a low resistance portion. The actuator has a motor configured to rotate the shaft, the motor outputting a current feedback signal to indicate current exiting the motor. The actuator has a interference portion disposed on a fixed member adjacent the shaft, the interference portion configured to facilitate a resistance to shaft rotation when the shaft rotates, the resistance to shaft rotation causing a magnitude of the current signal to be greater when the starting resistance portion passes in front of the interference portion than when the low resistance portion passes in front of the interference portion.
F16H 63/40 - Control outputs to change-speed- or reversing-gearings for conveying rotary motion comprising signals other than signals for actuating the final output mechanisms
A hydraulic actuator is configured to provide redundant boost control to an aircraft within approximately the same space required by a single hydraulic cylinder. The hydraulic actuator includes a housing and a piston assembly disposed within the housing. The piston assembly includes a ram, a first piston secured to the ram, and second and third pistons disposed on the ram such that the second and third pistons are translatable relative to the longitudinal axis of the ram. The pistons form two hydraulically separate actuator cylinders within the space required by a single cylinder which results in a reduction in the weight and size of the hydraulic actuator.
F15B 15/14 - Fluid-actuated devices for displacing a member from one position to anotherGearing associated therewith characterised by the construction of the motor unit of the straight-cylinder type
A servovalve includes a single motor which actuates separate valve members of separate servovalve assemblies. Each of the valve members controls the flow of hydraulic fluid from separate hydraulic fluid sources. In order to provide each valve member with the ability to operate in the event that the other valve member becomes inoperable, such as caused by jamming of the valve member, each servovalve assembly includes a compression assembly that provides each servovalve assembly with a jam-override capability.
F16K 31/04 - Operating meansReleasing devices electricOperating meansReleasing devices magnetic using a motor
F16K 11/065 - Multiple-way valves, e.g. mixing valvesPipe fittings incorporating such valvesArrangement of valves and flow lines specially adapted for mixing fluid with all movable sealing faces moving as one unit comprising only sliding valves with linearly sliding closure members
F16K 37/00 - Special means in or on valves or other cut-off apparatus for indicating or recording operation thereof, or for enabling an alarm to be given
34.
Lamination having tapered tooth geometry which is suitable for use in electric motor
An electric motor has a stator, and a rotor disposed within the stator. The stator has a set of stator laminations and a set of windings held in position by the set of stator laminations. The rotor is arranged to rotate about an axis. The set of stator laminations is arranged into a stack. Each stator lamination includes an outer section, and a set of teeth coupled to the outer section. Each tooth of the set of teeth extends from that outer section toward the axis. Each tooth has (i) a first end which is proximate to the outer section and distal to the axis, and (ii) a second end which is proximate to the axis and distal to the outer section. A width of the first end of each tooth is substantially greater than a width of the second end of each tooth.
A technique can recover from motor stalls caused by misalignment of motor position sensors such as Hall-effect sensors. In a normal operating mode, a motor controller provides motor drive current to the motor windings based on the sensor signals according to a normal commutation sequence, and monitors for occurrence of a motor stall condition. Upon detecting the motor stall condition, the motor controller first momentarily drives the windings according to one of an advanced commutation state and a delayed commutation state each adjacent to the given commutation state in the normal commutation sequence, and determines whether the motor stall condition persists. If the stall condition persists, then the motor controller next momentarily drives the windings according to the other of the advanced commutation state and the delayed commutation state. By this action, the controller attempts operation at both preceding and succeeding portions of the torque characteristic, such that operation with increased torque is ensured even though the direction of the sensor misalignment is unknown.
H02P 3/18 - Arrangements for stopping or slowing electric motors, generators, or dynamo-electric converters for stopping or slowing an individual dynamo-electric motor or dynamo-electric converter for stopping or slowing an AC motor
36.
Motor system employing analog encoded hall effect sensor position information for reduced wiring
A system has a sensor assembly mounted adjacent to a moving magnetic member such as a motor rotor to sense its position. The sensor assembly includes Hall-effect sensors each having a binary output, configured such that distinct positions of the moving magnetic member correspond to distinct digital patterns of the outputs of the Hall-effect sensors. Encoding circuitry is coupled to the outputs of the Hall-effect sensors to generate a multi-valued analog output, distinct values of the multi-valued analog output representing corresponding distinct digital patterns of the outputs of the Hall-effect sensors. The encoding circuitry may employ a ladder network with weighted-value resistors contributing different components of an analog current sensed by the controller. The sensed current can be converted to digital position information using suitable analog-to-digital conversion circuitry. The multi-valued analog output can be conveyed on a single wire in contrast to the prior art which requires one wire per Hall-effect sensor.
H02K 29/08 - Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices using magnetic effect devices, e.g. Hall-plates or magneto-resistors
A drive assembly for providing two outputs from a motor to actuators or the like has a first drive shaft connected with the motor via a torque limiter and a reduction gear. A high efficiency spur gear also connects the motor with a second, parallel drive shaft via a second torque limiter and a reduction gear. The two drive shafts are also interconnected by a low efficiency gear provided by worm pinions on the shafts and a worm gear wheel engaging both pinions, which only transfers load between the drive outputs if there is uneven torsional loading in excess of the settings of the torque limiters.
F16H 1/16 - Toothed gearings for conveying rotary motion without gears having orbital motion involving only two intermeshing members with non-parallel axes comprising worm and worm-wheel
B64C 3/38 - Adjustment of complete wings or parts thereof
