Abstract:
A method of continuouly forming edgewise wound cores from a continuous lanced strip of a ferromagnetic material having a pair of opposite faces interposed between a pair of opposite edges at least in part extending lengthwise of the lanced strip. In practicing this method, the lanced strip is continuously drawn through a bending zone in which at least the opposite edges are constrained, and the lanced strip is continuously deformed generally edgewise thereof about an axis of the bending zone so as to continuously from a plurality of helical convolutions. At least as the lanced strip travels beyond the bending zone, the lanced strip is pressed against a rotatable surface to effect the continuous drawing of the lanced strip through the bending zone.A core, a lanced strip, and apparatus are also disclosed.
Abstract:
A three-phase induction motor is subjected to countermeasure for the rotor and the stator in order to remove two harmonic components of the orders causing a torque ripple, among a plurality of harmonic components included in a magnetic flux generated in an air gap between a stator core and a rotor core. In the three-phase induction motor, conductor grooves of the rotor core are skewed by an electrical angle of 2.pi./n where n is the order of one of the harmonic components to be removed. In the stator, the number of slots (N) is selected so that an equation N=l.times.m.times.q is satisfied, where l=the number of poles, m=the number of phase, and q is a non integer number representing the number of slots per pole per phase, and the stator winding pitch is determined according to the order of another harmonic component to be removed.
Abstract:
A lanced strip of generally thin ferromagnetic material adapted to be edgewise wound into a core for a salient pole dynamoelectric machine. A continuous yoke section of the lanced strip extends generally lengthwise thereof and includes a pair of generally opposite edges, and a set of spaced apart notches in one of the opposite edges with each notch having an arcuate edge therein, respectively. A set of spaced apart teeth are integral with the other of the opposite edges and extend generally laterally from the yoke section, and the teeth includes a set of free end sections each having another arcuate edge defining at least a part thereof and with respective ones of the first named and another arcuate edges having a common centerpoint, respectively.A core for a salient pole dynamoelectric machine is also disclosed.
Abstract:
Apparatus for forming edgewise wound cores from continuous strip stock of a generally thin ferromagnetic material has a means operable generally at an intermittent rate for lancing the strip stock. The lancing means includes continuous driving means for effecting the operation of the lancing means at its intermittent rate and means operable generally for feeding the strip stock to the lancing means and the continuous strip therefrom concomitantly with the intermittent rate. Means arranged to receive the continuous step from the lancing means is operable continuously for deforming the continuous strip generally edgewise thereof into a plurality of generally helical convolutions. Variable drive means interconnected between the continuous driving means and the deforming means is operable generally for effecting the continuous operation of the deforming means at a variable rate to correlate the intermittent rate at which the continuous strip is fed from the lancing means with the continuous operation of the deforming means.A method of continuously forming edgewise wound cores is also presented.
Abstract:
A method of assembling a stationary assembly for a dynamoelectric machine includes associating at least one beam in a preselected assembly position with a core at least adjacent a circumferential portion thereof. A set of sections of the core at least adjacent the circumferential sections thereof are deformed into gripping engagement with the at least one beam, respectively, and thereby the at least one beam is retained against displacement from the selected assembly position thereof.
Abstract:
Apparatus for continuously forming edgewise wound salient pole cores from a continuous lanced strip of generally thin ferromagnetic material. The lanced strip includes a yoke section extending generally lengthwise thereof and having a pair of sets of segments therein with the segments of one of the segment sets being integrally interposed between the segments of the other of the segment sets, and a set of salient pole teeth integral with the segments of the one segment set so as to extend generally laterally from the yoke section. The apparatus has a pair of means operable generally for effecting generally edgewise deformation of only the segments of the other segment set in the yoke section of the lanced strip upon the continuous passage of at least the yoke section between the edgewise deformation effecting means.
Abstract:
Apparatus for forming edgewise wound cores from a continuous strip of generally thin ferromagnetic material has means operable generally for deforming the continuous strip into a plurality of generally helical convolutions thereof, and means is arranged for receiving the deformed helical convolutions from the deforming means and for accumulating the deformed helical convolutions into a generally axial stack thereof. The receiving and accumulating means includes a pair of relatively movable means associated with each other and operable generally for separation, and a set of means operable in one of said relatively movable means toward a preselected position for supporting at least some of the deformed helical convolutions received on said one relatively movable means when the other of said relatively movable means is separated therefrom, respectively.
Abstract:
For the iron cores of an electrical machinery and apparatuses, such as transformers, electric motors and generators, mostly a grain-oriented electromagnetic steel sheet is used. Since the grain-oriented electromagnetic steel sheet has a (110) [001]texture and is thus easily magnetized in the rolling direction, the direction of magnetic flux in the iron cores is required to be coincident with the rolling direction. However, this requirement cannot be completely fulfilled due to the shape and an operation efficiency of producing the iron cores as well as generation of a magnetic reluctance in the butted iron-core elements. Laser irradiation regions are formed, according to the present invention, for example, on the following: the parts of the iron core where the rotational magnetic field is generated; the entire surface of the I-type elements or: the major part of the E or C type element.As a result of the laser-irradiation, the watt loss is low even where the complete coincidence of the easy direction of magnetization and the magnetic flux direction is difficult.
Abstract:
A lanced strip of generally thin ferromagnetic material has a continuous yoke section extending generally lengthwise thereof, and a plurality of teeth on the lanced strip are aligned generally about a plurality of pitch axes therefor and extend generally laterally from the yoke section, respectively. A plurality of slots extend through the lanced strip between adjacent ones of the teeth, respectively. The yoke section includes a plurality of sets of generally arcuate inner and outer edges, the arcuate inner edges extend between the adjacent ones of the teeth thereby to define closed ends of the slots and adjacent ones of the arcuate outer edges intersect with each other at the pitch axes of the teeth, respectively.
Abstract:
An induction motor with an improved torque/slip characteristic has a solid rotor having longitudinal grooves running parallel to the axis of rotation which connect with circumferential grooves at each end of the rotor. The rotor is plated with copper so that the grooves are filled with copper. The rotor is then machined over the cylindrical outer surface to produce a solid, non-laminated rotor having high-conductivity paths in the longitudinal grooves connected by high-conductivity short-circuiting rings in the circumferential grooves.In a modification the longitudinal grooves may be skewed. Other high conductivity material may replace copper, for example aluminium.