Abstract:
A variable motor (1) having reduced audible noise. This advantage is achieved by reducing or eliminating ripple torque by making the individual phase torques follow a certain profile, so that when the torques are summed, they are substantially constant. Therefore, the motor (1) back EMF is used as a reference waveform to control the winding currents to achieve reduced ripple torque. The back EMF reference is amplified and provided to the motor windings, and may be derived in a number of ways including use of sense windings, electronic derivation, and approximation by sensing the voltage applied to the windings.
Abstract:
A rotor for a motor or generator is produced by placing separated magnets around the diameter of the potential rotor, placing separated segments of magnetic backing material behind the magnets, and embedding the whole in molding material in a mold in such a way that the segments thrust outwards against the magnets and the magnets thrust outwards against the mold during placement of the molding material.
Abstract:
A refrigeration controller within a retail refrigeration cabinet controls the temperature (502) so that it approaches the maximum allowable temperature by using the most efficient fan speed for loading and time of day (507) but is varied by customer presence (505) to adhere to an algorithm reducing the noise (506) created by such machines while still creating sufficient cooling to remain within the maximum temperature while providing acceptable power economy.
Abstract:
A beverage cooler has a low voltage DC supply (311) usable by the controller ancillaries, such as lighting (318), the DC supply also providing the supply voltage to a microprocessor (313) which electronically commutates at least one of the motors (305, 306, 307) associated with beverage cooling to provide a required speed or loading. The microprocessor also responds to and controls the cooler ancillaries, such as lighting, temperature and status reporting thereby allowing a reduced component count.
Abstract:
A winding for a toroidal electrodynamic machine is formed by providing a set of bobbins in a rectilinear array, winding the bobbins so that each phase is of one continuous wire, with each set of phases wound one bobbin at a time, the completed rectilinear array then being formed into a circular array for the machine. The rectilinear array has bobbins formed and is wired in such a way that bending into a torus is possible.
Abstract:
A method and apparatus for production of stator windings for dynamoelectric mechines of different configurations is provided. The windings are preferably formed on a bobbin (10) or similar article, which may then be transferred onto an appropriate carrier such as a ferromagnetic core (24). The core (24) may be provided as a substantial linear article and then be bent into an appropriate shape, so that the assembly may be provided as the stator of a dynamoelectric machine. In this configuration, only a portion of each winding will face the magnetic poles of the rotor and thus be operative, as the return path of the windings will not be used. However, the invention as disclosed also shows it is possible to build a drum rotor (39) with both external and internal rotors in order to make use of both portions of the windings on the ferromagnetic core (24).
Abstract:
A method for testing of animals being milked, the system including a plurality of milk meters. A portable remote control device is provided to input data to the milk meters, receive and store data from the milk meters and display at least selected data. The remote control device is pre-loaded with animal related data and information relative to animals being milked is transmitted from the remote control device to the milk meters. Transmission of information from the milk meter as a consequence of an animal being milked is transmitted to the remote control device to enable updating of a record relevant to the animal being or having been milked. The remote control device thus provides a single interface with all milk meters for the inputting and receiving of data.
Abstract:
A refrigeration controller within a retail refrigeration cabinet controls the temperature (502) so that it approaches the maximum allowable temperature by using the most efficient fan speed for loading and time of day (507) but is varied by customer presence (505) to adhere to an algorithm reducing the noise (506) created by such machines while still creating sufficient cooling to remain within the maximum temperature while providing acceptable power economy.
Abstract:
A discoidal brushless DC motor having a stator (507) carrying windings (503) arranged in slots which radiate out from the center of the stator to the periphery. The depth of each slot increases towards the center of the stator. The slot, therefore, is wider (from side to side) and shallower towards the periphery of the stator, and narrower (from side to side) and deeper towards the center of the stator. This arrangement ensures that the windings are contained below the surface (504) of the stator (507). The magnetic circuit includes a backing of a ferromagnetic material (509). This ferromagnetic material (509) can be a watch spring core made from a long strip of soft iron tape.