Abstract: A compound of the formula (I) wherein R1 is —X—R4, an optionally substituted heterocyclic residue, an optionally substituted carbocyclic residue or optionally substituted condensed ring moiety; X is CR5R6, O, S, SO, SO2 or NR7; Y is CH or N; R2 is H, an optionally substituted C1-C10 alkyl,etc.; R3 is an optionally substituted aryl, or an optionally substituted heteroaryl, etc.; R4 is an optionally substituted aryl, an optionally substituted heteroaryl, etc.; R5, R6, and R7 can be identical or different and represent H, an optionally substituted C1-C10 alkyl, etc. The compound has an excellent anti-allergic activity and the like.

Abstract: A trip device of a main circuit breaker is provided which causes only a branch circuit breaker to be set into a tripped state when an abnormal current occurs at a load of the branch circuit breaker while keeping a closed state of the main circuit breaker. The trip device of the circuit breaker has a structure including a trip latch mechanism for opening switching contacts, a stationary core, a movable core which is attracted to the stationary core to release the latch mechanism of a trip lever, an operating pin for interrupting movement of the movable core while the movable core is attracted, an operating spring charged with force when the movable core is attracted, and an inertia roller holding the operating pin, kicked when the operating spring discharges the force, and moved to a position which does not interrupt movement of the movable core. Accordingly, this structure allows a selective tripping system to be implemented simply with small size and low cost.

Abstract: Disclosed are .beta.-carboline derivatives represented by the formula: ##STR1## wherein R.sup.1 represents hydrogen atom, a lower alkyl group, a lower alkoxy group or hydroxy group; R.sup.5 represents hydrogen atom, or R.sup.1 and R.sup.5 are bonded to represent a lower alkylenedioxy group; R.sup.2 represents hydrogen atom, a halogen atom, a lower alkoxy group or hydroxy group; R.sup.3 represents hydrogen atom, a carbamoyl lower alkyl group, a lower alkyl group, a carboxy lower alkyl group or a lower alkoxycarbonyl lower alkyl group; R.sup.4 represents hydrogen atom, a lower alkyl group, a carboxy lower alkyl group, a lower alkoxycarbonyl lower alkyl group, a lower alkanoyl group, an arylcarbonyl group, a lower alkanesulfonyl group, a lower alkoxycarbonyl group, an aralkyl group, formyl group or a di(lower alkyl)sulfamoyl group; n represents 0, 1 or 2; and the symbol * represents an asymmetric carbon atom,or a pharmaceutically acceptable salt thereof, and a process for preparing the same.

Abstract: Disclosed is a circuit breaker including a first linking member for switching fixed contacts provided in a main current path. The first linking member is operated by a circuit switching mechanism using a voltage-operated electromagnet, a forced contact parting mechanism upon short circuit condition using a current-operated electromagnet connected in series to the main path, and a spring releasing mechanism responsive to flow of overcurrent for operating. The forced contact parting mechanism upon short circuit condition includes a link mechanism including self-retaining/self-resetting function between the first linking member and the current-operated electromagnet.

Abstract: It is the main object of this invention to provide a circuit breaker in which the movable contacts have sufficient opening force and opening distance, and in which the breaking time is short. In order to attain the object, the circuit breaker of this invention is provided with a dead center link mechanism comprising a movable contact link which is rotatably supported by the arms of a cross bar which is operated so as to be capable of opening-closing the circuit and tripping by means of a trip-free mechanism, and a toggle spring which is bridged between the cross bar and the movable contact link. When a large current such as a short-circuit current flows, a movable steel plate attracted by an electromagnet for instantaneously tripping hits a rod for supporting the movable contacts which is connected to the movable contact link, whereby the dead center link mechanism makes the movable contacts open at high speed from the fixed contacts.