328results about "Manufacturing cage rotors" patented technology

Ceramic adhesive is applied inside the slots of an electric machine squirrel cage rotor prior to casting or insertion of rotor conductors. This heat-resistant insulation provides superior electrical insulation that is also mechanically rugged, thus enabling casting of squirrel cage rotors by die or cost-effective consumable pattern casting. The consumable pattern cast copper rotors are electrically well insulated, thus minimizing rotor losses. The ceramic insulation in cast rotors enables longer conductors to be cast by thermally insulating the molten metal from the cooler laminations. The ceramic insulation in fabricated rotors withstands the high temperatures of end ring attachment. This method is applicable to both conventional induction machine rotors and brushless doubly-fed induction machine rotors and provides the degree of electrical isolation of the bars from the laminations needed to avoid excessive parasitic torques in doubly-fed machines, while ensuring adequate thermal conductivity to dissipate conductive bar heat to the laminations.

A rotor for a reluctance machine is provided. The rotor includes a cylindrical soft-magnetic element having cutouts for forming magnetic flux barriers. Some or all of the flux barriers are divided by one or more webs, with the profile of the individual webs forming a closed line which divides the rotor in the radial direction into an inner and an outer region. The cut-outs may be partially or fully filled with a a paramagnetic or diamagnetic filler material.

In a method of manufacturing a self-start synchronous motor for preventing deterioration of permanent magnets used in a rotor, and also for enhancing the efficiency of the self-start synchronous motor, the self-start synchronous motor comprising a stator having a stator core and windings wound around the stator core, and a rotor having an outer diameter slightly smaller than an inner diameter of the stator and arranged inside of the stator. The rotor is provided with a rotor core, a plurality of conductor bars embedded in the outer peripheral portion of the rotor core over an entire periphery thereof, end rings provided on opposite end sides of the conductor bars and constituting a squirrel cage conductor in cooperation with the conductor bars, and a plurality of permanent magnets embedded in the rotor core and arranged at a position inner than that of an inner peripheral surface of the conductor bars. Further, the conductor bars and the end rings are electrically and mechanically joined together through frictional agitation joint.

A rotor assembly and a method for fabricating the same are provided in which a solid rotor ring is formed at either end of a stack of laminated discs, the solid rotor rings yielding improved electrical and mechanical characteristics in a low weight assembly. The solid rotor rings are fabricated by brazing slugs between the end portions of the rotor bars, the braze joints contacting a large percentage (at least 90%) of the rotor bar end portions.

A rotor for an electric motor according to the invention comprises a substantially cylindrical core, conductive rods and two short-circuit rings. The cylindrical core is formed from a core material and provided with a plurality of longitudinal grooves which extend substantially in the direction of the cylinder axis. The conductive rods are formed from an electrically conductive material and are provided in the longitudinal grooves of the cylindrical core. The two short-circuit rings conductively connect the axial ends of the conductive rods to one another. A diffusion layer extends between the conductive rods and the cylindrical core. The diffusion layer comprises a diffusion material.

A method of making a squirrel cage rotor of copper material for use in AC or DC motors, includes forming a core with longitudinal slots, inserting bars of conductive material in the slots, with ends extending out of opposite ends of the core, and joining the end rings to the bars, wherein the conductive material of either the end rings or the bars is copper. Various methods of joining the end rings to the bars are disclosed including electrofriction welding, current pulse welding and brazing, transient liquid phase joining and casting. Pressure is also applied to the end rings to improve contact and reduce areas of small or uneven contact between the bar ends and the end rings. Rotors made with such methods are also disclosed.

A rotor assembly and a method for fabricating the same are provided in which a pair of end caps, positioned at either end of the stack of laminated discs, are fusion welded to the rotor bars using an electron beam welder, thereby yielding improved electrical and mechanical characteristics in a low weight assembly.

A method for fabricating an induction motor rotor lamination includes using an indexed notching die to punch a plurality of closed rotor slots at different distances from a center point of rotation by punching a first rotor slot, changing the position of a center point of the rotor lamination with respect to the notching die, and punching a second rotor slot. In another embodiment, a plurality of rotor slit patterns are punched using a variable depth indexed notching die including at least two rotor slit punching portions, one being deeper than another, by punching a first rotor slit pattern, changing the depth of closure of the notching die, and punching a second rotor slit pattern with the second rotor slit pattern having a different number of rotor slits than the first. In another embodiment, each rotor slit is open to and off center with respect to its respective rotor slot, and rotor laminations are stacked by positioning some of the rotor laminations in an orientation with is turned over and rotated with respect to others of the rotor laminations; filling the rotor slots and the rotor slits with cage material; and machining outer surfaces of the rotor laminations. In another embodiment, uniformly spaced identical rotor slots are punched and modulation is created by punching a contoured outside diameter or by inserting slot wedges of molded magnetic material.

A method of manufacturing a rotor assembly includes placing a generally cylindrical rotor core in a die. The rotor core has axial grooves spaced about a perimeter of the rotor core. The grooves may be formed by stacked laminated disks. Material is cast around the annular rotor core in the die such that the cast material forms conductor bars that fill the grooves and first end ring portions at opposing ends of the rotor core connected with the conductor bars. Each of the first end ring portions has substantially a first axial width. The rotor core with cast conductor bars and cast first end ring portions is then removed from the die. A respective second end ring portion is welded to each of the cast first end ring portions to form end ring assemblies. Each second end ring portion has a second axial width greater than the first axial width.

In accordance with one embodiment, the present technique provides an apparatus for assembling a rotor. The exemplary apparatus includes a base that has a central aperture and a seating surface for receiving the rotor. An arbor then extends through the central aperture, the arbor having a longitudinal axis that is substantially orthogonal to the seating surface, and including threaded ends opposite with respect to one another. The exemplary apparatus also includes at least one member of a family of fixtures coupleable to the arbor, the family including a pressure fixture that has first and second piston assemblies disposed at diametrically opposite locations to one another, the family also including a support fixture coupleable the arbor and having members extending axially therefrom, the members being configured to support securing members of the rotor. Advantageously, the exemplary apparatus provides for a mechanism through which a securing member may be symmetrically installed with respect to the rotor core, thus improving rotor performance and construction.

A procedure for casting a shorted structure around a plurality of induction motor rotors is described. The method comprises forming a wax representation of the shorted structure around a lamination stack; mounting a plurality of such lamination stacks in a mounting fixture and attaching a suitable gating and runner system; forming an investment by coating the structure with refractory followed by melting out the wax; casting molten metal into the investment while it is rotating and aligning the mold to allow the centrifugal force generated to promote mold filling; and, continuing to rotate the investment until solidification is substantially complete.

A method is disclosed for providing inorganic and/or organic coating compositions onto rotor cores to eliminate soldering during aluminum injection. These coatings can also be applied upon electric motor rotors and/or stators laminates as well as other electronic components such as transformers. The disclosed method provides at least one film or layer of a coating composition within channels or bar slots defined by the rotor of the electric motor core/rotor (depending upon the design of the motor the slots can be defined within the rotor or open ended along the longitudinal axis of the rotor). The coating composition is also typically applied upon all exposed surfaces of the rotor, e.g., within the channels and exterior surfaces of the rotor. The coated rotor is then contacted with a molten metal. The coating composition functions to isolate the laminates (e.g., steel) of the rotor from a molten metal (e.g., aluminum and its alloys), which surrounds the rotor and fills the channels thereby embedding the rotor, and prevents the metal from forming an undesirable conductive path typically termed soldering among the individual laminates.

A cage rotor of a rotary asynchronous machine includes an axially laminated core having substantially axially extending grooves, at least one electrical conductor disposed in the grooves and composed of at least of two partial conductors constructed from materials having different electrical conductivities and different mechanical strengths, wherein the partial conductor made of the higher-strength material is disposed radially farther outwardly at least in sections of the groove, as viewed along the axial extent of the respective, and a short-circuit ring arranged on a respective end face side of the laminated core and electrically-conductively interconnecting the electrical conductors that are disposed in the respective grooves and protrude axially from the laminated core.

According to one embodiment, the present invention provides a rotor assembly. The exemplary rotor assembly includes a plurality of rotor laminations, which cooperate to form a rotor core, capped at each end by end members. Extending through the rotor core and the end members, a plurality of rotor channels is configured to receive electrically conductive members therethrough. Each of the electrically conductive members has external portions, which extend beyond the rotor channel, and an interior portion that is housed within the rotor channel. By flexing the external portions, a compression force that secures the laminations and the end members with respect to one another may be provided. Advantageously, the external portions may be fused to one another and/or to the end members. As one example, the external portions may be fused through the introduction of a molten metal into the end member. Advantageously, fusing of the external portions to the end members and/or one another increases the mechanical integrity of the rotor and provides for good electrical communicativeness between the conductive members, for example.