Abstract: A method for making an armature assembly is provided that reduces the level of acoustic noise during initial engagement of the armature, during slippage, and during disengagement. The armature assembly includes an armature disc, an annulus of sound damping material, and a hub assembly having a flexible spider with a web portion. The armature assembly is made by first forming the annulus of sound damping material with a plurality of angularly spaced molding tabs. The annulus is affixed to the web portion of the hub assembly using the molding tabs and is then compressed by securing the armature disc to the web portion such that one side of the annulus is disposed against the web portion and a second side of the annulus is disposed against the armature disc.

Abstract: An armature for a selectively engageable and disengageable coupling and a method of making the armature are provided. The armature includes a substantially annular body that is disposed about a first axis. The body may be formed by stamping or fine-blanking. One side of the body is hardened through a nitriding process. A grinding wheel is then applied at an angle to the same side of the body along a diametrical line of the body extending perpendicular to the first axis. As a result, the body is configured so that the thickness of the body increases as the distance from the diametrical line increases. In particular, the thickness of the body varies along each cross-section taken along the line from a minimum thickness at the innermost portion of the cross-section to a maximum thickness at the outermost portion of the cross-section. The inventive armature reduces galling, and the resulting noise, that occur during burnishing of couplings incorporating the armature.

Abstract: A spring-set, electromagnetically released brake that requires a relatively small amount of current to release is provided. The brake includes a magnet shell disposed about a first axis. The shell includes a radially outwardly extending pole. The brake also includes an armature disposed radially outwardly of the pole and pivotable at a first axial end and a first engagement element, such as a brake shoe, coupled to the armature proximate a second axial end of the armature. The brake further includes a spring disposed about the pole. The spring biases the armature radially outwardly to urge the first engagement element towards a second engagement element such as a friction surface in a brake drum. Finally, the brake includes a coil disposed about the pole and means for selectively energizing the coil to urge the armature radially inwardly and the first engagement element away from the second engagement element. A bobbin for use in the brake is also provided.

Abstract: A rotor assembly and method for a dynamoelectric machine includes a shaft having an outer circumferential surface defining a shaft diameter. The rotor assembly also includes a plurality of laminations, wherein each lamination has a central opening defining an inner periphery. The inner periphery includes a plurality of radially inwardly extending compressible protrusions defining an inner diameter slightly smaller than the shaft diameter. The protrusions are compressed as a lamination is mounted onto the shaft to form a press fit between the lamination and the shaft.

Abstract: A bi-directional back stopping clutch is provided having a hollow outer race, or drum, disposed about a first axis. The outer race includes a radially inner friction surface. The clutch also includes an input member rotatably supported within the outer race and first and second brake shoes disposed within the outer race and in engagement with the input member. Each of the brake shoes includes one or more arcuate surfaces corresponding to the inner surface of the outer race with each arcuate surface defining a slot. The clutch further includes an output pin having a first portion disposed between the first and second brake shoes and a second portion disposed within an opening of an output member. Finally, the inventive clutch includes a hardened insert disposed within each of the slots in the arcuate surfaces of the brakes shoes. The inserts each include a groove formed therein which channels a lubricant within the clutch away from the frictional interface of the insert and the inner surface of the outer race.

Abstract: A motor system controller and a method of operating the controller are provided that enable automatic (i.e., without further user intervention), sequential display of selected parameter values. The controller includes a memory that stores a plurality of operating parameters associated with the motor system controller and a computer program. The controller also includes a user interface having an operator keypad and a liquid crystal display. The operator keypad can be used to access the memory and select certain of the operating parameters for sequential display. The computer program then works with the display to automatically, sequentially display values associated with the selected parameters. The method includes the steps of selecting parameters from a plurality of operating parameters associated with the motor system controller and automatically, sequentially displaying values associated with the selected parameters.

Abstract: An electromagnetic clutch in which an annulus of sound dampening material is sandwiched between an armature disc and a hub assembly, particularly a web portion thereof. The annulus and web coact to define a constrained-layer damping system for reducing noise when the armature disc is snapped into engagement with the rotor of the clutch, slipping prior to lockup, while the armature is magnetically locked to the rotor, and also during slipping and disengagement of the armature disc. The design provides a reduced axial-length package relative to prior armature assemblies incorporating constrained-layer techniques.

Abstract: An armature assembly for a selectively engageable and disengageable electromagnetic coupling is provided. The armature assembly includes a hub having a central axis that is disposed radially outwardly, and mounted for rotation with, a shaft used to drive an air-conditioning compressor. The assembly also includes a resiliently flexible spider disposed radially outwardly of the hub. The spider is fixed against rotation relative to the hub, but is able to flex axially relative to the hub at a hinge. The armature assembly further includes an annular armature disc disposed radially outwardly of the hub and connected to a first side of the spider. Finally, the armature assembly includes a counterweight disposed on a second side of the spider. The counterweight may be integral with the spider or connected to the hub.

Abstract: A system for controlling a stepper motor is disclosed that includes a microprocessor for directly generating current command signals. The microprocessor has a memory wherein the memory includes a function table, a first function table address, and a second function table address. A velocity signal (indicating a rotational position change per unit time) is calculated by the microprocessor during each update interval. Each update interval comprises a plurality of interrupt intervals. The microprocessor, in accordance with software-selectable current magnitude parameter values and microstepping parameter values, determines a first and second current value by accessing the function table at the first and second function table addresses, during each interrupt interval. The first and second current values generated by the microprocessor correspond to a pair of digital words representing a pair of phase current commands.

Abstract: A removable adapter (24) for use with a motor control unit (14) having mass-termination connectors (28, 30, 32) is provided. The adapter (24) includes a circuit board (36) having a first side (62) and a second side (64) opposite the first side (62). The adapter (24) further includes terminal strip (38, 40, 42, 44), which may include screw terminals (64), disposed on the first side (62) of the circuit board (36) and mass-termination connectors (46, 48, 50) disposed on the second side (64) of the circuit board (36). The mass-termination connectors (46, 48, 50) of the adapter (24) are configured to directly, matingly engage the mass-termination connectors (28, 30, 32) of the control unit (14).

Abstract: A spud assembly is provided for use in a pneumatically actuated brake, clutch or other friction assembly. The spud assembly includes a spud and a washer that are configured to reduce axial and rotational movement of the spud within the friction assembly. The spud includes a body portion that is centered about a first axis and extends through an aperture in a holding plate of the friction assembly. The body portion includes an outer wall that defines a pair of diametrically opposed flats. The flats engage a corresponding pair of flats in the washer which is fixed against rotation relative to the friction assembly holding plate. The spud also includes a holding member, such as a circular flange, that extends radially outwardly from the body portion of the spud. The holding member abuts one side of the holding plate to reduce axial movement of the spud.

Abstract: A method and circuit for controlling a motor and reducing and/or eliminating mid-velocity instability in the motor are provided. The method includes the step of receiving a decay time indicative signal that is indicative of the current decay time in a phase coil of the motor after current commutation. The decay time indicative signal assumes a first polarity proportional to the current decay time in the phase coil. The method further includes the step of calculating a delay time corresponding to the amount of time the decay time indicative signal has the first polarity. Finally, the method includes the step of controlling the direction of current in the phase coil or another phase coil of the motor responsive to the delay time and a current direction signal generated by a translator. The inventive method and circuit enable reduction and/or elimination of mid-velocity instability even when the motor is operated in a microstepping mode.