Abstract: Controller for a three-phase brushless D.C. motor has a full bridge circuit and an electronic control unit (ECU). The full bridge circuit has three branches each with switches connected to the motor windings. The switches are driven by signals from the ECU. The drive signals are arranged in two sets of three signals. The two sets are offset by 180 electrical degrees. The drive signals of each set are offset by 120 electrical degrees and each have an active portion, alternating with an inactive portion. The active portion includes an initial interval of pulsed activation, an intermediate interval of continuous activation, and a final interval of pulsed activation. The active portion of the drive signals is greater than 120 electrical degrees, with each initial interval of pulsed activation of a switch overlapping the final interval of the previously activated switch.

Abstract: A rotor of an electric motor has a carrier structure including a disc portion to which is centrally connected a shaft, and the periphery of which is joined to an essentially cylindrical annular skirt portion which in use extends coaxially around the stator. The disc portion has a plurality of slots between which there is defined a corresponding plurality of spokes. At least some of the spokes have, in a circumferential direction, a transverse cross-section shaped in a manner to induce, at least when the rotor rotates in one direction, an at least approximately axial air flow through corresponding slots.

Abstract: A permanent magnet rotor for a brushless electric motor of the kind with an internal stator, has a carrier structure of molded plastic that includes a disc portion fixed to a shaft. The disc portion has a periphery joined to a substantially cylindrical cage portion coaxial with the shaft. The cage portion accommodates a magnetic flux conducting structure forming an wall which is coaxial with the shaft, and a plurality of permanent magnets shaped as ring segments, disposed at angular intervals within and adjacent to the flux conducting structure. Each magnet has its circumferentially terminal faces parallel with each other or converging in the outward direction. The cage portion is overmolded onto the flux conducting structure and has a plurality of angularly spaced struts which are essentially parallel to the axis of the rotor and which protrude radially inwards.

Abstract: Controller for a three-phase brushless D.C. motor has a full bridge circuit and an electronic control unit (ECU). The full bridge circuit has three branches each with switches connected to the motor windings. The switches are driven by signals from the ECU. The drive signals are arranged in two sets of three signals. The two sets are offset by 180 electrical degrees. The drive signals of each set are offset by 120 electrical degrees and each have an active portion, alternating with an inactive portion. The active portion includes an initial interval of pulsed activation, an intermediate interval of continuous activation, and a final interval of pulsed activation. The active portion of the drive signals is greater than 120 electrical degrees, with each initial interval of pulsed activation of a switch overlapping the final interval of the previously activated switch.

Abstract: A stator connector has an annular carrier structure adapted to be superposed on and fixed to the central annular portion of the stator and manufactured from an electrically insulating plastic overmolded onto a group of N conducting members which are separated from each other and electrically insulated by said plastic and having a generally arcuate shape. The conducting members have respective first projections extending out of the annular carrier structure. These first projections are adapted to be connected, in particular by soldering or welding, to terminals or ends of coils of the stator. Each conducting member further has at least one additional connection projection extending out of the annular carrier structure to form phase terminals for the stator.

Abstract: A permanent magnet rotor for an brushless electric motor of the kind having an internal stator, has a supporting structure made of molded plastic that includes an essentially disc-shaped portion to which a shaft is centrally connected. The periphery of the disc is joined to an essentially cylindrical cage portion which extends coaxially around the shaft. A plurality of magnetically conductive yokes are disposed in the cage portion. The yokes are shaped as ring segments which as a whole form an essentially cylindrical wall. A plurality of ring segment permanent magnets are each disposed astride the junction of a pair of adjacent yokes. Each yoke has a dimension which increases from the circumferential ends thereof towards its circumferentially intermediate portion, such that the cross-sectional area of the yoke in a radial plane correspondingly increases from the ends thereof towards its intermediate portion.

Abstract: A starting system for an internal combustion engine of a vehicle includes a second motor configured to drive a second load, a first motor configured to selectively drive either the engine or a first load, and a controller configured to control the first and second motors such that when the first motor drives the engine the second motor is stopped, and when the first motor drives the first load the second motor is controlled to drive the second load. Preferably, the second load is a cooling fan of a cooling system for the engine and the first load is a water pump of the cooling system.

Abstract: A permanent magnet rotor for an brushless electric motor of the kind having an internal stator, has a supporting structure made of molded plastic that includes an essentially disc-shaped portion to which a shaft is centrally connected. The periphery of the disc is joined to an essentially cylindrical cage portion which extends coaxially around the shaft. A plurality of magnetically conductive yokes are disposed in the cage portion. The yokes are shaped as ring segments which as a whole form an essentially cylindrical wall. A plurality of ring segment permanent magnets are each disposed astride the junction of a pair of adjacent yokes. Each yoke has a dimension which increases from the circumferential ends thereof towards its circumferentially intermediate portion, such that the cross-sectional area of the yoke in a radial plane correspondingly increases from the ends thereof towards its intermediate portion.

Abstract: A permanent magnet rotor for a brushless electric motor of the kind with an internal stator, has a carrier structure of molded plastic that includes a disc portion fixed to a shaft. The disc portion has a periphery joined to a substantially cylindrical cage portion coaxial with the shaft. The cage portion accommodates a magnetic flux conducting structure forming an wall which is coaxial with the shaft, and a plurality of permanent magnets shaped as ring segments, disposed at angular intervals within and adjacent to the flux conducting structure. Each magnet has its circumferentially terminal faces parallel with each other or converging in the outward direction. The cage portion is overmolded onto the flux conducting structure and has a plurality of angularly spaced struts which are essentially parallel to the axis of the rotor and which protrude radially inwards.

Abstract: A stator connector has an annular carrier structure adapted to be superposed on and fixed to the central annular portion of the stator and manufactured from an electrically insulating plastic overmolded onto a group of N conducting members which are separated from each other and electrically insulated by said plastic and having a generally arcuate shape. The conducting members have respective first projections extending out of the annular carrier structure. These first projections are adapted to be connected, in particular by soldering or welding, to terminals or ends of coils of the stator. Each conducting member further has at least one additional connection projection extending out of the annular carrier structure to form phase terminals for the stator.

Abstract: A rotor of an electric motor has a carrier structure including a disc portion to which is centrally connected a shaft, and the periphery of which is joined to an essentially cylindrical annular skirt portion which in use extends coaxially around the stator. The disc portion has a plurality of slots between which there is defined a corresponding plurality of spokes. At least some of the spokes have, in a circumferential direction, a transverse cross-section shaped in a manner to induce, at least when the rotor rotates in one direction, an at least approximately axial air flow through corresponding slots.