Abstract: A method of testing the residual stress around a cold-worked hole in a test material. The test uses two identical eddy current coil pairs, each pair having a driving coil and a pickup coil. One coil pair is placed into the cold-worked hole. The other coil pair is placed into a non-cold worked hole in a reference material. When the coils are activated, and with a properly chosen phase difference between the excitation signal and the output signal, the in-phase component of the output voltage signal can be correlated to residual stress around the cold-worked hole.

Abstract: A flexible eddy current probe for non-destructive testing of a metallic object, the probe having a flexible printed circuit containing eddy current drive and sense coils and a rotary encoder configured to measure liner distance as the eddy current probe is scanned over the object. The probe features an encoder arm that adjustably connects a flexible eddy current sensor array to the rotary encoder.

Abstract: A probe capable of inducing a rotating magnetic field to excite a conductive tube includes an array of magnetic field sensors to detect and characterize defects in the tube. The probe includes a circumferential coil assembly and an axial coil assembly both positioned to induce eddy currents in the conductive tube, such that the magnetic field sensors can detect defects in the tube, including defects extending circumferentially, axially, or any combination thereof, whether at the surface or sub-surface of the tube inner and outer walls.

Abstract: A stator assembly for a fuel valve comprising a magnetic E-core of stacked E-shaped laminations, a plastic bobbin proportioned to surround a central leg of the core, a magnetic wire coil on the bobbin, a non-magnetic metal plate having an O-shaped profile adjacent an end of the bobbin and distal ends of central and outer legs of the E-core, the core, bobbin, coil and plate encapsulated in a block, the block having a pair of vent channels overlying portions of the plate disposed between the outer core legs and the central core leg, the plate being proportioned to pre-stress the outer core legs outwardly prior to encapsulation whereby cyclic strain on the block due to hydraulic forces imposed by high pressure fuel pulses tending to spread the outer core legs is reduced and resistance of the block to cracking due to said fuel pressure pulses is increased.

Abstract: A metering device (24) for an agricultural planter (10) has a metering chamber (80) with a seed discharge (98) area and a metering disc (66) rotatable within the metering chamber (80). The metering disc (66) has plurality of seed pockets (68) for carrying seeds on the metering disc (66), the seed pockets (68) being disposed at mutually spaced locations about the metering disc (66). The metering disc also has a magnetic drive ring (136) in the outer periphery of the metering disc (66). The metering device also has a stator positioned adjacent the metering disc. The stator (132) interacts with the magnetic drive ring (136) to rotate the metering disc (66) within the metering chamber (80) such that the seed pockets (68) move successively in proximity to the discharge area (98) during rotation of the metering disc (66).

Abstract: A bistable relay may include a pair of contact arms. Each contact arm is configured to have a first end and a second end, such that, when the relay is in the closed position, current flows from the first end to the second ends of each of the contact arms, and when the relay is in an open position, current does not flow from the first ends to the second ends of the contact arms. The relay further includes a motor, a pair of springs, a pair of cams driven by the motor, and a linearly actuating member configured to move the contact arms from the first configuration to the second configuration, the member including a cam follower surface.

Abstract: A combined current transformer and metering system is described, having a securable case, two or more current transformers each having a core and secondary windings connected to a secondary circuit, wherein the transformers are mounted within the case. A wiring harness connects the secondary windings of the transformers with shorting current switches for short circuiting the secondary current circuit, and voltage switches for disconnecting a voltage, wherein both sets of switches are mounted on the case. A process of manufacturing the system is described, wherein the transformer cores are positioned within the case, the wiring is connected between the transformer cores and attachment hardware on an upper deck of the case, and insulation medium is inserted within the case. A base plate is described, having rails to hold the system and having a tab at one end, and apertures for a rod positionable between rails at a second end.

Abstract: A bistable relay may include a pair of contact arms. Each contact arm is configured to have a first end and a second end, such that, when the relay is in the closed position, current flows from the first end to the second ends of each of the contact arms, and when the relay is in an open position, current does not flow from the first ends to the second ends of the contact arms. The relay further includes a motor, a pair of springs, a pair of cams driven by the motor, and a linearly actuating member configured to move the contact arms from the first configuration to the second configuration, the member including a cam follower surface.

Abstract: In a method and a device for determining a reference position of a locking part moved by an electric motor, the locking part is moved in the direction of the closed state thereof, until the same reaches a stop position. At that location the meter reading of a position meter describing the stop position is detected and buffered. Subsequently a movement of the locking part is carried out in the direction of the opened state thereof. The locking part is then moved again in the direction of the closed state thereof, until it again reaches a stop position. At that location a meter reading describing the stop position is detected, and compared to the buffered meter reading. If both meter readings agree, the first stop position is determined as the reference position. The method and device can be utilized, for example, for power window lifts and sunroofs of motor vehicles.

Abstract: An eddy current probe assembly suitable for inspecting a test object with longitudinal shape, being passed through the assembly in the object's axial direction during an inspection session, the probe assembly comprising multiple probe modules being disposed in a radial plane and with the modules partially overlaying on each other forming an iris structure encircling an inspection zone, wherein a movement in unison of each of the probe modules closer to or further away from the center of the inspection zone makes the inspection zone enlarged or contracted. Spring tension is applied on each of the probe modules so that constant life-off in maintained between the probe modules and the test surface. Array of eddy current elements for each probe module and multiple layers of probe modules can be employed to achieve complete coverage of the test surface. The radial cross-sectional shapes of the test objects can be of round or polygonal.

Abstract: A method (and corresponding apparatus) for monitoring gas turbine blades. The output from an eddy current sensor monitoring the movement of turbine blades past the sensor is processed to determine when the signal train from the sensor omits a signal or pulse corresponding to one of the shaft's full complement of blades. The signal processor compares sensed blade periods with average blade periods.

Abstract: A battery health or prognosis system may employ a ferrite disc embedded in a printed wiring board (PWB) to perform both a battery current sensing role and a temperature sensing role. The ferrite disc may be surrounded with a coil that may be comprised of surface conductors and electrically conductive vias of the PWB. Excursions of coil current may be produced to generate observable hysterisis loops in the ferrite disc. The generated hysterisis loops may be compared to a temperature-dependent family of hysterisis loops for the magnetic material from which the ferrite disc is constructed. A processor mounted on the PWB may collect and process outputs from a Hall-effect sensor to develop both temperature and battery current information to produce a prognosis for the battery.

Abstract: A method (and corresponding apparatus) for monitoring the rotational speed of the shaft of a gas turbine having a number of spaced blades on or rotating with the shaft. The invention compensates for the errors which arise from the relative movement of turbine blade tips by deriving a correction factor for each blade and continually updating that correction factor.

Abstract: A method for detecting small cracks and other anomalies on parts having complex geometries is disclosed. The method includes eddy current inspection incorporating collection of data from multi-frequency eddy current signals. Phase analysis is used to combine the multi-frequency data to enhance the signal to noise ratio of the raw inspection image. The image is then reprocessed using a spatiotemporal filter to correlate with the frequency components of the eddy current flaw signal to separate signals associated with cracks and other flaws at edges that would ordinarily be hidden by edge effect signals.

Abstract: The invention relates to a device and a method for determining an electrical starting rotor angle of an electromotor. According to the invention, the electromotor (10) is subjected to an approximately sinusoidal voltage and the corresponding current path (i) that is established is then detected. The electromotor (10) is again subjected to an approximately sinusoidal voltage and again, the corresponding current path (i) is detected. A ratio of a measure of the fundamental wave (I1) and the measure of the first harmonic wave (I2) is then determined from the current paths (i) as a measure of the electrical starting rotor angle (?).

Abstract: Magnetic shields for plastic molded electricity meter frames are positioned to substantially block external magnetic fields from adversely affecting operation of meter components. The shield can be utilized with either electromechanical or electronic energy meters. In an electromechanical watthour meter which employs an aluminum disk driven to rotate through a magnetic field produced by a retarding magnet, the meter frame includes an integrally formed retarding magnet shield and an integrally formed bearing shield. The shields are coextensive with the frame, and extend from an inner periphery of the frame toward the retarding magnet and the bearing, respectively. The shields are formed of a magnetically permeable powder, such as a ferrite powder mixed with the plastic material from which the meter frame is molded. The shields divert externally applied fields away from the magnetically sensitive components of the meter without adversely affecting meter accuracy.

Abstract: Magnetic shields for plastic molded electricity meter frames are positioned to substantially block external magnetic fields from adversely affecting operation of meter components. The shield can be utilized with either electromechanical or electronic energy meters. In an electromechanical watthour meter which employs an aluminum disk driven to rotate through a magnetic field produced by a retarding magnet, the meter frame includes an integrally formed retarding magnet shield and an integrally formed bearing shield. The shields are coextensive with the frame, and extend from an inner periphery of the frame toward the retarding magnet and the bearing, respectively. The shields are formed of a magnetically permeable powder, such as a ferrite powder mixed with the plastic material from which the meter frame is molded. The shields divert externally applied fields away from the magnetically sensitive components of the meter without adversely affecting meter accuracy.

Abstract: A retarding magnet assembly includes magnets configured to apply a constant drag on the rotating disk of an electromechanical electricity meter. The assembly includes upper and lower keepers secured to opposing extensions of the meter frame. A spacer is secured, at a first end, to the upper keeper, and a non-magnetic flexure spring is secured to a second end of the spacer. A pair of upper magnets are secured to the flexure spring member at opposing ends. A pair of lower magnets are secured to the lower keeper at opposing ends. The meter rotating disk extends between the upper and lower magnets. The equilibrium point of the flexure spring changes, depending on strength of the upper magnets and their consequent attraction to the upper keeper. Thus, if the upper magnets becomes stronger due to a temperature change, the attraction of the upper magnets to the upper keeper increases, and the upper magnets move closer to the upper keeper.

Abstract: An apparatus for recording information about the angular motion of a rotatable disk disposed in a first structure is provided. The disk has regions with differing properties with respect to electromagnetic energy. The apparatus includes first means for emitting a first sequence of electromagnetic energy pulses in a first direction toward the disk. The first emitting means are mounted on the first structure adjacent a first side of the disk. The apparatus also includes second means for emitting a second sequence of electromagnetic energy pulses in a second direction toward the disk, the second emitting means also being mounted on the first structure adjacent the first side of the disk. The first and second directions are such that the first and second sequences of electromagnetic energy pulses reflect from the first side of the disk in different areas, the areas being separated in the direction of rotation of the disk.

Abstract: An electro-mechanical induction watt-hour meter bearing system that includes end cap pilot bearings snap fit onto respective opposite ends of the shaft. The bearing system also includes a lower shaft support bearing selectively adjustable in increments for controlled adjustment.

Abstract: An apparatus and method to detect and avoid inaccuracies in an electronic energy meter due to reverse rotation of the eddy current disk in response to pull-back and creep of the disk, or tampering, including the detection of reverse rotation by checking each three successive states of light transmission between two light emitter/detector pairs in response to an optical castellated disk passing between the emitter/detector pairs, storing pulses generated by the reverse rotation and subtracting the stored pulses upon a subsequent reversal of rotation to the forward direction. Upon reverse rotation in excess of one revolution, the stored pulses are counted along with the counting of the additional reverse rotation pulses and an error signal is generated for subsequent display in response to a command signal.

Abstract: A sensor for detecting the rotation of an eddy wheel in an electric power meter is described. The sensor includes a pair of light sources arranged to focus light on the edge of the wheel, and a light detector arranged to sense reflections from the edge of the wheel caused by the light from the light sources. The light from either sensor is sufficient to trigger the detector, thereby requiring a sufficiently large interruption in the reflection, for example as caused by a mark on the edge of the eddy wheel, to interrupt the detector output. A filter is described for eliminating jitter in rotation of the eddy wheel.

Abstract: Non-magnetic metallic spacers are welded into the auxiliary air gaps of a voltage stator using welding passes arranged in a predetermined sequence. The presence of the spacers stabilizes the auxiliary air gap against change in light load adjustment. Sequences of welding passes are disclosed effective for holding inherent light load error at nominal values, or biasing it positively or negatively.

Abstract: A disk for an electric meter includes a solid annulus of a conductive material with a center of the annulus filled with a non-conducting material. The non-conducting material is preferably molded in place both to capture the annulus and to secure a disk shaft into a unitary assembly. The annulus distorts eddy currents at distances from sets of potential and current stators of the electric meter to minimize radial components of eddy currents in the vicinity of neighboring sets of potential and current stators. The reduced radial components of eddy currents reduces the constructive or destructive interaction of the eddy currents with their neighboring sources of flux. Increasing the angular separation of the sets of potential and current stators further reduces interaction.

Abstract: A polyphase, socket-style meter employs identical left and right current stators. The angles about the meter disk, at which the left and right current stators are located, are adjusted to place the centers of their cores in alignment with their connector tabs. Identical current stator coils encircle the cores. The axes of the cores are slightly skewed with respect to the axes of the coils. The diameters of the coil helices are made large enough to accommodate the skew.

Abstract: A brushless motor (10) comprises a stator yoke plate (16) made of a magnetic material, to which both main surfaces the first and the second flexible printed circuit boards (20) (22) formed integrally including a connecting part (24) are stuck respectively. On the first flexible printed circuit board (20), a plurality of driving coils (30) are arranged annularly and a conductor pattern for a speed detecting coil is formed inside the driving coils (30). On the integrated stator yoke plate (16) and the first and second flexible printed circuit boards (20) (22), a penetrated hole (18) for passing through a rotor shaft (54) is formed generally in the center. A tongue (36) is formed generally in protrusion inwardly from the periphery defining the penetrated hole (18) on which a connecting conductor pattern connected to the speed detecting coil is formed.

Abstract: A watthour meter frame for an electric watthour meter includes pairs of orthogonal machined plane surfaces against which bearings are urged for accurately positioning the ends of a disk shaft of an electric watthour meter. Clearances are provided in the watthour meter frame for machining all pairs of machined surfaces without either changing the cutting tool or rotating the watthour meter frame. Worm gear bearings are similarly positioned in the watthour meter frame against three machined plane surfaces which may be machined in the same operation, and with the same cutting tool, as used in forming the pairs of machined surfaces for the disk shaft bearings. The worm gear bearings include a cylindrical barrel which is resiliently urged into contact with a pair of plane machined surfaces in a bearing well and a positioning flange having a bearing surface which is resiliently urged into a face surface surrounding the bearing well.

Abstract: A flux shunt includes a pickup plate parallel to, and closely spaced from, an outer surface of a voltage stator winding of a voltage stator for an electric meter drive apparatus. A flux-return tab of the flux shunt passes through an auxiliary coil and enters a flux-return slot in the voltage stator core of the voltage stator. The flux-return tab is biased into intimate mechanical contact with a surface of the flux-return slot both to prevent buzzing and to provide a low-reluctance return path for flux picked up by the pickup plate. The return flux, passing through the auxiliary coil induces a voltage in windings thereof for powering meter accessories such as, for example, a light-emitting diode whose illunination is indiciative of excitation of the core material of the voltage stator.

Abstract: A light load adjustment for an electric meter includes a frame attachable to a core of a voltage coil and a pole-shading element slideable with respect to the frame. The pole-shading element includes a windowed plate or a pair of tabs interposeable between the core of the voltage coil and the rotatable disk and effective to change the direction and magnitude of the torque applied to the rotatable disk of the electric meter at light load. A single adjusting screw for the light load adjustment is placed in one of its two alternative positions. In either of its two alternative positions, rotation of the head of the adjusting screw by a worker facing the head produces a displacement of the windowed plate or tabs which tends to change the disk speed in a sense which is consistent with the convention for the relationship between the direction of rotation of an adjustment and the change in disk speed.

Abstract: A multiple rate metering system suitable for use with an existing single rate, electromechanical electricity meter employing an Eddy current disc mounted in a casing, comprises a first unit mountable inside the casing of the electricity meter, and a second unit, which is portable so that it can be brought into close proximity with said first unit by a meter reader. The first unit comprises a sensor for generating pulses in response to rotation of the Eddy current disc, a first microprocessor, a first read-only-memory for storing a program to control the operation of said first microprocessor, a random-access-memory, the first microprocessor being programmed to store data in said random-access memory related to the pulse count in different predetermined periods during which different electricity rates apply, and a first coupling device for establishing communication through the casing with said second unit when said second unit is brought into proximity with said first unit.

Abstract: The electronic watt-hour meter (10) comprises an electro-optical watt-hour sensor (12) adapted to be coupled to a consumer's connection to a source of electric power for sensing voltage supplied to, and the current drawn by, the consumer's electric load and for producing output signals indicative of a quantity of watt-hours of power utilized by the consumer. In the meter (10) a microprocessor (22) is coupled to the sensor (12) for receiving output signals therefrom and a memory (29) is coupled to the microprocessor (22) for receiving and storing data. A power supply (24) supplies D.C. power to the microprocessor (22) and includes a clock signal generator to supply a 60 Hz. clock signal to the microprocessor (22). Also a visual display (30) is coupled to the microprocessor (22) for providing a readout of the power consumed since the last reading of the solid state watt-hour meter.

Abstract: A temperature compensated magnetic damping assembly for providing a braking torque on an electroconductive disk of an induction device includes a pair of permanent magnets each having an easy axis of magnetization. Each permanent magnet provides two easy flux paths parallel to the easy axis of magnetization and separated by a dead zone. The permanent magnets are juxtaposed about a predetermined space through which the disk rotates such that the easy flux paths are perpendicular to the disk, and are aligned such that the magnetic flux passes twice through the disk in opposite directions. Flux return plates are provided adjacent to each of the permanent magnets so as to provide a flux path parallel to the disk and linking the two easy flux paths of each of the permanent magnets. In this configuration, a highly-efficient, substantially square magnetic flux loop is provided. One of the flux return plates is movable relative to the adjacent permanent magnet so as to provide series adjustment of the damping torque.

Abstract: An induction meter has an improved voltage magnetic section comprised of a substantially E-shaped laminated magnetic core having a center leg and two adjacent legs. A nonmagnetic multi-function support and spacer bracket extending from one of the adjacent legs to the other adjacent leg has three perpendicular extensions which give the bracket a substantially E-shaped configuration and which each are riveted to one of the legs of the magnetic core. The perpendicular extension riveted to the center leg provides support for the voltage coil. A light load adjuster bracket provides an adjustable shunt path for magnetic flux between the main pole face and the auxiliary pole faces. The light load adjuster bracket is located in magnetic proximity to the first side of the magnetic core and is separated therefrom by the nonmagnetic bracket.

Abstract: An induction meter having a voltage magnetic section comprised of a substantially E-shaped laminated magnetic core having a center leg terminating at a main pole face and two adjacent legs terminating at coplanar auxiliary pole faces on opposite sides of the main pole face provides a fixed light load adjuster bracket located in magnetic proximity to the first side of the core. The bracket has a fixed tab extending over a portion of one of the auxiliary pole faces. A nonmagnetic spacer is located between the first side of the core and the light load adjuster bracket. The spacer, the light load adjuster bracket and the laminae of the core are fastened together so as to provide a rigid assembly. The light load adjuster bracket carries a movable tab extending over adjustable portions of the other auxiliary pole face and the main pole face thereby providing an adjustable magnetic flux shunt path.

Abstract: The present invention is for an induction meter having a voltage and a current magnetic section. The voltage magnetic section is comprised of a substantially E-shaped laminated magnetic core having a center leg terminating at a main pole face and two adjacent legs terminating at coplanar auxiliary pole faces on opposite sides of the main pole face, and includes a spacer bracket located between a first side of the voltage magnetic core and a first voltage shunting member. The spacer bracket carries a self-aligned, light load adjustment assembly having a movable tab extending over portions of one of the auxiliary pole faces and the main pole face thereby providing an adjustable magnetic flux shunt path. A second voltage shunting member is located in magnetic proximity to the first side of the core and spaced from the first voltage shunting member by a nonmagnetic spacer.

Abstract: A brake magnet for watt-hour meters using permanent magnet material of low permeability of nearly one and high coercive strength in which exact temperature compensation for a required temperature range can be achieved and which is easily manufactured. The temperature compensation elements are positioned on the surfaces of the brake magnet system away from the air gap.

Abstract: Unidirectional rotation of a register is produced by a ratchet assembly having a pivoting pawl member having two diverging wire segments, each of which discretely engages either of two sets of ratchet teeth. A transfer means couples input rotations of the rachet assembly in a false registering direction so as to produce rotations of the assembly output in a true registering direction.

Abstract: A watthour meter with a rotatable metering movement responsive to the flow of energy through the meter includes a gravity activatable contact or stop element to engage the metering movement when the meter is inverted for preventing deregistration of consumed energy. Latching means can lock the element in a position showing that the meter had been inverted.

Abstract: A direction sensitive pulse initiator for a watthour meter having a rotating disc. A pair of sensors sense the presence of an indicator portion or portions, on the rotating disc or on an auxiliary disc, to produce electrical signals which are decoded to initiate clockwise rotation pulses and/or counterclockwise rotation pulses. The pulses are available to be recorded for compiling a record of metered power over a period of time. The sensor electrical signal outputs are decoded so as to determine if the previous exit direction of the indicating portion is the same as its present entry direction, and if this is true a rotation pulse of the appropriate direction is produced.

Abstract: A magnetic damping system for induction devices having electroconductive disk armatures includes a low induction, high coercive force magnet that is vertically elongated and has a horizontal direction of magnetization parallel to the disk. Flux concentrating pole pieces adjoin the magnet pole faces for vertically directing two closely spaced braking magnetic fields from a pair of pole tips and into the disk. A temperature compensating arrangement covers the sides of the permanent magnet between the edges of the pole pieces to efficiently compensate for higher reversible temperature coefficients of magnet remanence.

Abstract: A repulsion-type permanent magnet bearing system for watthour meters includes identical upper and lower permanent magnet assemblies. Each assembly includes a hollow cylindrical magnet including a temperature compensating sleeve extending through each magnet center opening. Soft magnetic shielding cups are attached to the rotor and stator parts of the meter to carry the permanent magnet assemblies in facing relationships. The permanent magnet size and orientation with respect to each other and the cups provides an optimumly maintained bearing gap spacing.

Abstract: An electromagnet for use in an extremely inverse time overcurrent relay, wherein extremely inverse relay performance is obtained as a result of the electromagnet's simplified design. The electromagnet comprises a core having two E shaped portions of unequal size, each portion including a base wall, two outer legs and an inner leg, with the inner legs of the two portions being arranged in aligned opposition. The opposed and aligned inner legs of the core constitute magnetic pole members having opposed faces spaced apart and defining an air gap therebetween. Each pole member is provided with a shading ring shading the pole member by greater than 50%. Further, the electromagnet is provided with a single energizing means located on the core for establishing a flux distribution in the air gap whereby a rotatable armature which may be located in the air gap may be driven in response to an energizing current.

Abstract: A single disc multielement polyphase watthour meter having first and second electromagnetic assemblies which apply torque to the disc, the electromagnetic assemblies being mounted with the longitudinal axes thereof located respectively in spaced parallel planes extending parallel to a baseplate of the meter. The meter register includes only decade gearing and the input drive member thereof is coupled to a shaft which mounts the disc over a coupling gear box which includes ratio gearing which adapts a given register for use in registering power consumption in power systems of different current and power ratings.

Abstract: An opto-electronic pulse initiator for producing meter data pulses from a meter having a rotating movement. A directionally oriented pattern containing at least two reflective surfaces is driven by the meter movement to sequentially activate first and second optical sensors. The sensors are activated in opposite sequences in response to opposite rotations of the meter movement. A solid state pulse initiating circuit is utilized and includes low power digital integrated circuit elements, including a clocked bistable logic circuit. The optical sensors are connected to the inputs of the bistable logic circuit to produce predetermined mutually opposite binary logic states at the outputs of the bistable circuit, with the logic states corresponding to a given direction of meter movement. Data pulse output channels are controlled by the bistable logic circuit to selectively produce meter data pulses for a predetermined direction of rotation of the meter movement.

Abstract: A new and improved magnetic damping system for induction watthour meters including electromagnetically driven disk armatures. The magnetic damping system comprises cobalt-rare earth permanent magnets of relatively small mass deployed in a counterposed pair of unit assemblages each of which is positioned on an opposite side of the driven disk.

Abstract: A restraining means of mildly magnetic material is adjustably implanted in the rotor disc of a conventional watthour meter. The restraining means interacts with a magnetic field generated by the meter's damping magnet to stop the disc from turning when the rate of energy consumption in the metered circuit is below a predetermined rate. The predetermined rate can be altered by varying the radial distance between the center of the disc and the restraining means and by varying the amount of magnetic material passing through the field of the damping magnet.