Abstract: An assembly for transferring current comprises at least one electrically conductive slip ring; at least one electrically conductive brush for supplying current to the at least one slip ring; and an electric or pressure actuator driven vibration source for changing the position of the brush with respect to the slip ring. If desired, brush current can shared by using inductance variations or by selective coupling of rotor windings to the slip rings.

Abstract: A direct current machine monitoring system includes a current sensor for monitoring load current of the machine; and a computer for obtaining a power spectrum in a range including a machine trait-passing frequency, determining a magnitude of a maximum peak in the power spectrum in a range including the trait-passing frequency plus or minus an uncertainty frequency, and evaluating the magnitude of the maximum peak to assess a condition of the machine. The computer may additionally or alternatively be used for obtaining a low frequency power spectrum of the load current, obtaining at least one magnitude of a component of the power spectrum at a respective predicted frequency, and evaluating the at least one magnitude of the component to assess the condition of the machine.

Abstract: An electrical current collector system (20) comprises a rotatable shaft (28) having at least one and preferably plural electrically conductive slip rings (27) mounted thereon. For each phase, a slip ring is paired with a fixed conducting ring assembly (44). The fixed conducting ring assembly forms an envelope within which slip ring-contacting members are situated. The slip ring-contacting members can take many forms, including brushes (240) or rollers (404). The fixed conducting ring assembly comprises a first conducting plate (200T) and a second conducting plate (200B) positioned parallel to one another to form a conductive ring channel (220) therebetween. The slip ring-contacting members (240, 404) are mounted in the conductive ring channel. An at least partially transparent wall (200W) extends between the first conductive plate and the second conductive plate of the fixed conducting ring assembly to further define the conductive ring channel and permit visual inspection of the slip ring-contacting members.

Abstract: An electrical current collector system (20) comprises an electrically conductive slip ring (27) mounted to a rotatable shaft (28), as well as a fixed conducting ring assembly (44) having slip ring-contacting members (240, 404) mounted thereon. The slip ring (27) and fixed conducting ring assembly (44) are mounted to have an annular gap (48) formed therebetween. A slip ring support assembly (42) comprising plural post insulators (102) spaced radially about the rotatable shaft attaches the conductive slip ring to the rotatable shaft. The slip ring and fixed conducting ring assembly are at least partially enclosed in a compartment (57), to which a source (302) applies a cooling/cleaning fluid. In accordance with the structure and method of the invention, the source directs the fluid over at least some of the post insulators for cleaning of the post insulators.

Abstract: An electrical current collector system (20) comprises an electrically conductive slip ring (27) mounted to a rotatable shaft (28), as well as a fixed conducting ring assembly (44) having slip ring-contacting members (240, 404) mounted thereon. The slip ring (27) and fixed conducting ring assembly (44) are mounted to have an annular gap (48) formed therebetween. A slip ring support assembly (42) comprising plural post insulators (102) spaced radially about the rotatable shaft attaches the conductive slip ring to the rotatable shaft. The slip ring and fixed conducting ring assembly are at least partially enclosed in a compartment (57), to which a source (302) applies a cooling/cleaning fluid. In accordance with the structure and method of the invention, the source directs the fluid over at least some of the post insulators for cleaning of the post insulators.

Abstract: An assembly for transferring current comprises at least one electrically conductive slip ring; at least one electrically conductive brush for supplying current to the at least one slip ring; and an electric or pressure actuator driven vibration source for changing the position of the brush with respect to the slip ring. If desired, brush current can shared by using inductance variations or by selective coupling of rotor windings to the slip rings.

Abstract: An assembly for transferring current comprises at least one electrically conductive slip ring; at least one electrically conductive brush for supplying current to the at least one slip ring; and an electric or pressure actuator driven vibration source for changing the position of the brush with respect to the slip ring. If desired, brush current can shared by using inductance variations or by selective coupling of rotor windings to the slip rings.

Abstract: A method for fabricating a stack of motor laminations comprises forming cooling holes in each of the motor laminations and stacking the motor laminations with respective ones of the cooling holes in the laminations at least partially coincident to form a staggered cooling passage by having at least some of the cooling holes extending further into the cooling passage than others of the cooling holes. In one embodiment, the cooling holes can be perturbed cooling holes which are radially displaced from another cooling hole, azimuthally displaced from a hole axis, having an asymmetrical shape, being a different size from another cooling hole, or being shaped so that the rotation and stacking of a subsequently applied lamination results in a situation wherein adjacent cooling holes are not precisely aligned.