Abstract: The invention concerns a method and system for storing and displaying an entity relationship diagram. The entity relationship diagram of the invention is composed of only four different classes of allowed entity types. Thereby redundancy is eliminated and less storage locations are needed to store the diagram. The diagram comprises kernel entity sets K, attributive entity sets A, role entity sets P and relation entity sets R which are displayed on a display 9.

Abstract: This invention relates to a filtering apparatus for filtering liquids, in particular beverages. To attain an effective seal between two superimposed filter supports and the associated filter bodies in such a filtering apparatus, the upper side of an underlying filter support has formed therein a groove which opens upwards and has a substantially trapezoidal cross section and whose interior groove wall is substantially parallel to the inner wall of the apron of the filter support respectively lying thereabove, and the profiled seal has, on the whole, a substantially rectangular cross section, with the profiled seal portion supported on the respectively lower filter support being adapted to the cross section of the groove.

Abstract: A conventional on-off voltage regulator responsive to the output voltage of the rectifier of a vehicular battery charging system, operates three circuits each containing a pulse transformer and its driving transistor and other components for controlling the three SCRs that provide the negative side of the rectifier bridge, so that they will either pass entire halfwaves or block completely. The other three rectifier elements of the bridge are ordinary diodes. With this arrangement the SCRs may have the same rating as the other diodes of the bridge, and the thermal load is evenly distributed, while an alternator having a permanent magnet field can be used.

Abstract: To provide a positive indication that a battery has been reversely connected to a self-contained electrical network, for example a vehicular or boat network, a diode (24) of low current carrying capacity is connected across the terminals (25, 26) of the network, poled in blocking direction. Upon erroneous or reverse connection of the battery (13) with reverse terminals, the diode will immediately burn out, thus providing positive identification of such a reverse connection, even if only of such short time duration that the main rectifier diodes were not yet damaged. To prevent spurious replacement of the diode and thus elimination of the indication, the diode (24) can be molded into or cemented into a depression or groove formed in the insulating support plate (28) supporting the rectifier element.

Abstract: A conventional on-off voltage regulator operates a set of power MOSFET switches interposed between the grounded terminal of the battery and each of the diodes of a bridge rectifier leading to that terminal. Each such switch is controlled through an individual circuit responsive to the regulator output and including an opto-electronic device controlling a thryistor which, in addition to being connected to control the MOSFET switch, also has a connection through a resistor and a diode to the other side of the rectifier diode switched by the MOSFET. The circuit greatly simplifies voltage regulation of a battery charging system using an alternator with a permanent magnet rotor.

Abstract: The electrical system of a motor vehicle is protected against damage due to voltage sources, either the own battery or an external source, connected with wrong polarity by the combination of a diode and relay switches. In one embodiment, the diode is connected to the battery so that current flows only when the battery is connected with the correct polarity. The relay coil connected in series with the diode controls contacts which connect the battery to the rest of the circuit only when current flows through the diode. Alternatively, or in conjunction with this type of circuit, a shunting diode can be provided through which current flows only when the battery is connected with incorrect polarity. When current flows through this shunting diode, it also flows through the contacts of excess current cutout which then open to disconnect the battery from the remainder of the circuit.