Abstract: A motor is connectable to a single-phase AC power supply and forms a hermetic compressor. The motor includes a main circuit connected in parallel with the auxiliary circuit, and a winding structure having a main winding arranged as part of the main circuit and an auxiliary winding arranged as part of the auxiliary circuit. The motor includes a rotor arranged to be rotated by a current in the winding structure. To provide a motor durable and cheap to manufacture and to ensure a suitable response to overload situations, the auxiliary circuit has a first section and a second section extending in parallel where an NTC is inserted in the first section. A PTC is inserted in the second section, and a relay is arranged to activate and deactivate current in the first section of the auxiliary circuit based on a current level in the main circuit.

Abstract: The invention concerns a rotor of an electrical machine, particularly a driving motor for a hermetically enclosed refrigerant compressor with a body (4) comprising a magnetically conductive material, the rotor having a plurality of axially extending slots (5, 6), which are filled with an electrically conductive material. It is endeavored to achieve a good performance.

Abstract: The invention provides a rotor for an electrical motor. The rotor comprises both a squirrel cage and a number of magnets and can be inserted e.g. in a line-start motor. To secure the magnets in cavities in a core of the rotor, an end plate is attached to one axial end face by rivet means, and to simplify manufacturing of the rotor, the rivet means forms part of at least one of the short circuit rings of the squirrel cage.

Abstract: The invention provides a rotor for an electrical motor, e.g. a line-start motor. The rotor comprises a magnet located in a cavity in a rotor core. The core is laminated from sheets of magnetically conductive material and the magnet is secured in the cavity by an end plate which covers the end face. To avoid short circuiting of the magnet, an aperture is provided in the end plate such that a first portion of the opening into the cavity is in communication with the aperture and such that a remaining, second, portion of the cavity is covered by the end plate to secure the magnet in the cavity independently upon the orientation of the end plate around the center axis.

Abstract: The invention concerns a rotor of an electrical machine, particularly a driving motor for a hermetically enclosed refrigerant compressor with a body (4) comprising a magnetically conductive material, the rotor having a plurality of axially extending slots (5, 6), which are filled with an electrically conductive material. It is endeavoured to achieve a good performance.

Abstract: The invention provides an electrical line-start motor comprising with a stator and a squirrel cage rotor adapted for rotation around a centre axis. The rotor comprises a squirrel cage winding in which a current is induced by corresponding windings of the stator, and a set of permanent magnets. To protect the magnets from excessive heat, the rotor comprises thermal barriers e.g. in the form of cavities located between the squirrel cage winding of the rotor and the magnets. Due to the thermal barriers, the thermal conductivity in a path between the windings and the magnets are reduced and the magnets are protected.

Abstract: The invention provides a method of making a squirrel cage rotor for an electrical motor, and to a rotor for such a motor. The rotor comprises a rotor stack of a magnetically conductive material and a squirrel cage of an electrically conductive material. At least one of the short circuit rings are made by compression and sintering of a powder in which a solid element is embedded. The solid element facilitates manufacturing by increasing strength of potentially weak areas of the rotor, e.g. around openings into the shaft bore, rotor slots etc.

Abstract: The invention provides a rotor for an electrical motor, a tool for making a rotor core and a method of making the rotor. The rotor could be incorporated e.g. in a line-start motor and comprises a squirrel cage and magnet located in a rotor core. The magnets are, in one end of the rotor, secured by an end plate with apertures which are larger than the magnet openings, and the end plate is indexed relative to the magnet slots such that a first portion of openings into the magnet slots is in communication with the aperture and such that a remaining, second, portion of the magnet slots is covered by the end plate. In one aspect, the end plate forms an integrated part of the rotor core and comprises openings cooperating with conductor slots to form through-going passages for conductors of the squirrel cage. In that way, the end plate is held in a completely fixed position by the squirrel cage which is moulded directly onto the core and into the conductor slots.

Abstract: The invention concerns a starter for a line start electric motor having at least one main winding (4) and at least one start winding (12) and which start winding is connected in series with a run capacitor (14) with which a start capacitor (17) and a PTC-thermistor (19) are connected in parallel. In order to make a simply constructed starter for a line start electric motor the start capacitor (17) and the PTC-thermistor (19) are connected in series with a switch mechanism (20). The series connected circuit made up of the start capacitor (17), the PTC-thermistor (19) and the switch mechanism (20) is connected in parallel with the run capacitor (14).

Abstract: The invention relates to a rotor for an electric motor, especially an electric line-start motor, comprising spaces (4 to 7) which receive permanent magnets (10 to 13) and extend in an axial direction, and spaces (20 to 25) that accommodate conductor rods and extend in an axial direction. In order for the rotor to run as regularly as possible, the spaces (20 to 25) accommodating the conductor rods are provided with a substantially elongate cross-section in at least one sector of the rotor while being embodied in a curved manner along the longitudinal axis thereof in said sector when viewed from a cross-sectional perspective.

Abstract: The invention relates to a rotor for an electric motor, particularly an electric line-start motor, comprising axially accommodating spaces (4 to 6) for conductor rods, and axially extending receiving spaces (10, 11) for permanent magnets (14, 15), which are-designed and located in such a way that they generate a permanent magnet field with a magnet axis (22) and a neutral axis (23). The aim of the invention is to ensure that the rotor runs as regularly as possible during the operation of the electric motor. To this end, the diameter of the rotor along the magnet axis is larger than that along the neutral axis (23).

Abstract: The invention concerns a stator for a line-start electric motor, with a rotor accommodating chamber, in which a rotor is accommodated to be rotatable, and which has accommodating chambers for conducting rods and accommodating chambers for permanent magnets, and with a stator winding comprising several windings, which, during operation of the line-start electric motor under the influence of the rotor, generate a magnetic field with a main axis. In order to increase the efficiency of the line-start electric motor, the rotor accommodating chamber has no constant inner radius, but, in the area of a vertical to the main axis, has a larger inner radius than in the adjacent areas.

Abstract: In a method for starting an electric motor, which is operated by alternating current and which has a stator (1) with a main winding (H) and a first auxiliary winding (AUX1) and a rotor with permanent magnets and at least one short-circuit winding, it is ensured that, in order to avoid a pole changing when starting against a high load torque until the rotor has reached synchronism with the rotating field generated by the stator windings, that first auxiliary winding (AUX1) and a second auxiliary winding (AUX2) of the stator (1) are alternatingly supplied with the alternating current in dependence of the alternating current polarity, until the rotor has reached an oversynchronous speed, after which the alternating current supply to the auxiliary windings (AUX1, AUX2) is interrupted or reduced, the current of the auxiliary windings (AUX1, AUX2) being supplied phase-shifted in relation the alternating current (iH) being supplied to the main winding (H).

Abstract: Specified is an electric motor with a stator (1) that displays a rotating-field-generating rotating-field winding arrangement and a bore (3) in which is arranged a rotor.

Abstract: The invention relates to an electric motor, comprising a rotor (1). One side of said rotor (1) is mounted in a stator (3) by means of a bearing (2) and the rotor tapers away conically from said stator in an axial direction, forming an air gap (4) between the latter (3) and the rotor. The width of said gap increases in an axial direction, moving away from the bearing (2). The aim of the invention is to achieve improved operating efficiency using a conically designed rotor.