Abstract: The present invention provides a method and machine for producing a slotted wound core (50). The machine includes a punch arrangement (16) arranged to punch apertures in a length of material (12a), a mandrel (22) for receiving the punched material, a control means and a mandrel indexing means. The positioning of the punch arrangement (16) and the mandrel (22) is fixed and the mandrel (22) is arranged to be rotated by the mandrel indexing means after each operation of the punch arrangement so that a roll of punched material is formed on the mandrel (22). The mandrel (22) is rotated by an amount (&ggr;) determined by the control means. The control means determines the indexed amount so that selected apertures punched in the length of material align with one another when the material (12a) is rolled onto the mandrel (22) so that the aligned apertures form respective slots (52) of a desired configuration in the core (50).

Abstract: The present invention provides a method and machine for producing a slotted wound core (50). The machine includes a punch arrangement (16) arranged to punch apertures in a length of material (12a), a mandrel (22) for receiving the punched material, a control means and a mandrel indexing means. The positioning of the punch arrangement (16) and the mandrel (22) is fixed and the mandrel (22) is arranged to be rotated by the mandrel indexing means after each operation of the punch arrangement so that a roll of punched material is formed on the mandrel (22). The mandrel (22) is rotated by an amount (&ggr;) determined by the control means. The control means determines the indexed amount so that selected apertures punched in the length of material align with one another when the material (12a) is rolled onto the mandrel (22) so that the aligned apertures form respective slots (52) of a desired configuration in the core (50).

Abstract: The present invention provides a method for controlling the output power of a permanent magnet electric motor (102) using a control means (106). The control means (106) includes a means (134) for measuring motor speed (134) and motor phase current (134), and a means for controlling motor phase current (110) to a desired level. A known relationship between motor phase current and motor torque is then employed by a torque controller so that motor shaft torque can be controlled. A power limiting means (128) then limits the output mechanical power of the motor by dividing a limit value of power by the motor speed to produce a maximum allowable torque setting for that speed.