Abstract: A causality detection apparatus for detecting causality of events based upon a database provided with log of the events includes a sorter module for generating an event list by sorting in time sequence the events, and a frequency analysis module for calculating, based upon the event list, the number of appearance of an event set pair <X,Y> of a first event set X(={e.sub.x1,e.sub.x2, . . . ,e.sub.xn, . . . }, e.sub.xn indicates an event and n is a natural number) and a second event set Y(={e.sub.y1,e.sub.y2, . . . ,e.sub.yn, . . . }, e.sub.yn indicates an event), the number of appearance of the first event set X and the number of appearance of the second event set Y. The event set pair <X,Y> has co-occurrence so that the second event set Y occurs within a predetermined time period (window size W) after a time of occurrence of the first event set X.

Abstract: Plural thin plate projecting portions are integrally and projectingly provided on an outer peripheral portion of a side plate member of a bobbin. Each of the thin plate projecting portions comprises a circumferential rib, a slit portion and a reinforcement rib. The circumferential rib is provided on an outer peripheral face of the thin plate projecting portion of the bobbin and then a gap is formed between a claw-shaped magnetic pole of a rotor core and the thin plate projecting portion. A varnish material etc. is caused to adhere to and harden in this gap. By filling a root portion of the claw-shape magnetic pole of the rotor core with varnish material, the resonance vibration in the rotor core can be restrained. As a result, an alternating current generator for use in a vehicle having the small magnetic noise can be obtained.

Abstract: In order to cool a rotating electrical machine having an open cooling circuit, mechanically filtered environmental air is normally passed through the cooling ducts in the stator and rotor and the machine air gap (22) by means of fans (15) which are arranged on both ends of the rotor shaft. If the air which is taken from the environment is contaminated with hazardous materials, it is proposed to supply the prefiltered air directly to the stator and the machine air gap and to subject only the cooling air which is to be supplied to the rotor to refiltering in an activated charcoal filter (30). In this case, the mechanically filtered cooling air which is to be supplied to the stator and possibly the machine air gap is passed through the fans, while the refiltered cooling air which is to be supplied to the rotor is passed into the rotor on a separate route. The cooling air for the rotor is in this case preferably conveyed by the rotor's own ventilation.

Abstract: Each of the two brush leafs of an electric motor comprises a first resiliently flexible conductive section, attached to a terminal, and an additional resiliently flexible section extending an acute angle to the first section. The first and second ends of the first section are disposed on opposite sides of a contact portion of the additional section which engages a commutator forming part of the motor. It is therefore possible to increase the length of the first section to thereby provide robust brush leafs which are nevertheless capable of flexing sufficiently to accommodate discrepancies in the mounting of the brush leaf means and in concentricity of the commutator.

Abstract: A dynamoelectric machine has a rotatable shaft which extends through and is exposed in an end shield to secure a part such as an impeller thereto. To secure the shaft against rotation for attachment of the part thereto, the shaft and end shield are provided with axially aligned bores through which a rod may be journaled.