In a method of manufacturing a self-start synchronous motor for preventing deterioration of permanent magnets used in a rotor, and also for enhancing the efficiency of the self-start synchronous motor, the self-start synchronous motor comprising a stator having a stator core and windings wound around the stator core, and a rotor having an outer diameter slightly smaller than an inner diameter of the stator and arranged inside of the stator. The rotor is provided with a rotor core, a plurality of...

An air conditioning system is arranged to use a power line for communication. The air conditioning system includes one or more indoor units, one or more outdoor units, and a system controller for controlling the indoor units or outdoor units and executes communications between the indoor units and the outdoor units as overlapping a signal on the power line for supplying electric power. The outdoor units are connected with the system controller through a leased communication line. The indoor unit...

The invention provides a motor comprising a stator and a rotor. The stator core includes a laminated stator core made of laminated stator core plates in which straight cut surfaces are formed on a circular outer peripheral surface of the laminated stator core plates. The straight cut surfaces of the laminated stator core plates are circumferentially displaced every predetermined laminated stator core plates so that the straight cut surfaces are uniformly distributed in an axial and a circumferen...

The invention provides a vacuum insulation panel to which moisture and gas do not easily adsorb while it is being processed or being in storage in an unfinished state. The vacuum insulation panel includes a core provided with air circulation, a getter material which adsorbs moisture and gas from the core, an inner film bag which accommodates the core and the getter material, and an outer barrier bag which accommodates the inner film bag. The getter material is filled in an incision provided on t...

The invention relates to a vacuum insulation panel which can be used as an insulator for a refrigerator requiring heat insulation to be provided and also to a refrigerator incorporating such a vacuum insulation panel. The invention particularly relates to an arrangement for preventing convection spaces from being formed where an edge of the vacuum insulation panel is folded back. The vacuum insulation panel includes a core which has an inner film bag in which a flexible inorganic fiber laminate ...

A converter includes a converter circuit 1 having a plurality of bridge-connected semiconductor switching devices for converting AC power into DC power, a smoothing condenser connected in parallel to the DC side of the converter circuit and a current detector provided in a condenser circuit to control a condenser current flowing through the smoothing condenser to be a set value. The condenser current is controlled to be the set value (e.g. zero) to thereby reduce the capacity of the smoothing co...

In order to make a displacement type compressor be able to reliably start without increasing an outside diameter dimension of the compressor while using a self-start synchronous motor having high energy efficiency, the displacement type compressor according to the invention includes the self-start synchronous motor which starts as an induction-motor and performs synchronous operation by performing synchronization pull-in almost at a synchronous rotational frequency, a compression part having a c...

A permanent magnet synchronous motor includes a rotor having cage windings and permanent magnets placed on an inner peripheral side of these cage winding bars, where the permanent magnets are placed and polarized so that a ratio .theta./.alpha. between a circumferential pitch angle .theta. of magnetic flux distribution of the permanent magnets and a magnet pole pitch angle .alpha. is between 0.67 and 0.91.

A heat-pump hot water supply apparatus, for dissolving problems of delaying in heating rise-up time when re-starting, and ill influences upon starting characteristics, due to liquid refrigerant residing in an evaporator when the operation is stepped, within a heat-pump circuit thereof, comprises a heat-pump refrigerant circuit, in which a compressor, a water/refrigerant heat exchanger, a refrigerant adjusting valve, and an evaporator, in series, through refrigerant pipes, a direct hot-water supp...

An air conditioner and a power line communication system high in reliability and free of malfunction facilitates the installation work such as the wiring. The air conditioner for conducting communication through a power line includes a bridge unit connected to at least an outdoor unit through a transmission line, and at least an indoor unit connected from the power line through a blocking filter. A side of the bridge unit far from the outdoor unit is connected between the blocking filter and the...