Abstract: Improved techniques for rendering a peripheral device removable (e.g., unpluggable) are disclosed. According to one aspect of the invention, the peripheral device is rendered removable from a host computer without preparatory user actions. In effect, the peripheral device can be automatically prepared for removal in the event that its user removes (unplugs) it from its host computer. According to another aspect of the invention, the peripheral device includes a data storage device that is mounted to a file system of the other computer when the other computer desires access to the data storage device. Otherwise, the data storage device is normally unmounted so that if the peripheral device were to be removed (e.g., unplugged) no harm or damage to data stored therein would occur. These aspects of the invention can be utilized alone or in combination with one another.

Abstract: The present invention provides a method and apparatus for monitoring an infusion pump (10). The method and apparatus provides an encoder (101) which is used with a motor (65) of the infusion pump (10) and a monitoring method which effectively provides rotational directional information. The present invention utilizes a state transition of a first switch (111) indexed against a constant signal from a second switch (113) corresponding to the center of a flag (117) or sector (119).

Abstract: An electronic switch circuit for controlling a main circuit including a power source and a load, the electronic switch circuit including (a) an electromagnetic relay device including an electromagnet and at least two contacts, the electromagnetic relay device being connectable in series to the power source and the load of the main circuit; (b) a controlled semiconductor device being a part of the electronic switch circuit; (c) a semiconductor command circuit being connected to the semiconductor device, the semiconductor command circuit serving for controlling the operation of the controlled semiconductor device; (d) a relay command circuit being connected to the electromagnet of the electromagnetic relay device and to the semiconductor command circuit, the relay command circuit serving for controlling the relay device and the semiconductor command circuit; (e) an overload sensor serving for determining a current load flowing through the main circuit and for reporting the relay command circuit of a current ove

Abstract: A mounting construction of a tank-type lightning arrester for a neutral point of a transformer includes a transformer having a transformer winding contained within a transformer tank, the transformer winding having a neutral point, and a tank-type lightning arrester having an overvoltage protection element contained within a lightning arrester tank. A first opening is formed in an upper portion of a side surface of the transformer tank, and a second opening is formed in the lightning arrester tank, and the first and second openings are connected together through an insulating spacer having a central conductor, and the neutral point of the transformer winding is connected to the overvoltage protection element via the central conductor. The lightning arrester tank is supported solely by a mounting portion provided on a side surface of the transformer tank.

Abstract: A device for applying unipolar electrical charges to a moving, essentially electrically conductive insulating surface. An elongated corona electrode, e.g., including a number of tip electrodes, along with one or more auxiliary electrodes, and an electrically conductive counter electrode, are provided. The counter electrode supports the insulating surface, and a high-voltage d.c. source is connected to the electrodes. A carrier made of electrically insulating material is provided in the form of a channel, including a bottom wall and two side walls. The free edges of the side walls face the counter electrode. The corona electrode is arranged in the channel and at the bottom wall, and does not project over the free edges of the side walls. The auxiliary electrode(s) is arranged at, or in the vicinity of, each edge of the side walls, between the corona electrode and the counter electrode. One pole of the high-voltage d.c.

Abstract: A protection system for a three-phase distribution transformer immersed in a liquid dielectric contained in a tank, at least two of the three phases being equipped on the high voltage side of the transformer with respective current-limiting fuses. On each of the two phases equipped with current-limiting fuses, a protective micro-fuse is also connected in series with the current-limiting fuses and which operates faster than the current-limiting fuse. In addition, each micro-fuse is associated with a striker which, in turn, is connected to a mechanical trigger system which causes a three-phase short-circuiting device connected across the three phases to close in the event of a micro-fuse operating. Furthermore, the system includes at least one fault detector detecting one of pressure in the tank or the level of the dielectric. In particular, the three-phase short-circuiting device is situated on the high voltage side of the transformer between the current-limiting fuses and the high voltage windings.

Abstract: An arrangement for driving actuator coils for two or more driven devices employs a microprocessor or similar controller and an actuator driver circuit. The actuator driver circuit controls two or more relay actuator coils from a single microprocessor output terminal. This output terminal can provide a high, low, or pulse output signal. An amplifier switching device, such as a transistor, whose base is coupled to the output terminal of the microprocessor, drives the first relay actuator coil as its load. A rectifying diode is connected to one end of a capacitor and thence through a negative resistance device to a second relay actuator coil or other driven device. The coil impedances are selected so that the second coil has a significantly higher impedance than the first coil. When output pulses appear at the microprocessor output terminal, the transistor switch pulses on and off, and thus energizes the first coil.

Abstract: A non-burnout controller for a switching coil is disclosed. The controller has a pulse timer, a relay switch, and an actuation switch. After being reset and actuated, the pulse timer defines a pulse having a predetermined pulse period. The relay switch has a switch actuation input for receiving the pulse and first and second switch outputs for being electrically coupled to first and second taps of the switching coil. The relay switch places a switching voltage across the outputs during the pulse period such that the switching coil has a switching current running therethrough. The relay switch places a substantially zero voltage across the outputs before and after the pulse period such that the switching coil has substantially no switching current running therethrough. The actuation switch has first and second positions. Upon being changed to the first position, the actuation switch resets the timer, whereby the switching coil has substantially no current running therethrough.

Abstract: A transient switching circuit is provided to generate a voltage signal with fast voltage switching phenomenon during the initial ESD transient. The voltage signal is applied to a current spike generator for generating a current spike which forward bias an n+/pwell diode for injecting minority carriers into a substrate on which ESD protection device is embodied. The injected minority carriers are used to trigger turn-on of the ESD protection device. These minority carriers flow toward the drain-substrate junction of the NMOS transistor such that the NMOS transistor is triggered at a trigger voltage lower than that provided by the prior arts. The present invention improves the ESD performance of an ESD protection device, such as a MOSFET or bipolar transistor, which is provided for protecting the power bus or IC pins during an ESD event.

Abstract: A voltage surge suppression system for the protection of electronic equipment from damage from voltage surges and voltage transients has at least one metal oxide varistor electrically connected to a primary power source; a transformer; at least one second metal oxide varistor electronically connected between said transmission interceptor and a power circuit board; and a circuit opener electronically connected between the a transformer and power circuit board; wherein the a transformer is connected between the primary power source and second metal oxide varistor. The circuit opener is a resettable breaker for protecting the transformer from surges greater than the rated value of the second metal oxide varistor by opening in order to close off current flow.

Abstract: A transient oscillating circuit is provided to generate a series of current pulses for triggering turn-on of an ESD protection device. As VDD-to-VSS voltage increases rapidly in the initial ESD event, the series of current pulses injects minority carriers into the pwell of an NMOS transistor via an adjacent n+/pwell diode. These minority carriers flow toward the drain-substrate junction of the NMOS transistor such that the NMOS transistor is triggered at a trigger voltage lower than that provided by the prior arts. The present invention improves the ESD performance of an ESD protection device, such as a MOSFET or bipolar transistor, which is provided for protecting the power bus or IC pins during an ESD event.

Abstract: A circuit for protecting internal logic circuits of an integrated circuit (IC) device from a failure of internal voltage supply is disclosed. A protection circuit is connected between the internal power supply and an external power supply. The protection circuit reduces the external power to the internal logic circuits. A pass circuit is connected to the protection circuit and the internal power supply. The pass circuit is configured to reduce the input voltage difference in the protection circuit in the event of a failure of the internal power supply to prevent a failure of the protection circuit. The voltage level of the external power supply is typically higher than the internal supply voltage level, and exposure to the full external voltage level may disable the protection circuit.

Abstract: The electronic trip device with a thermal memory including a capacitor and a charging resistor arranged in parallel. In normal operation, the capacitor is permanently charged by a supply voltage supplied by the power system to be protected. The trip device includes a processing circuit which performs tripping functions after calculation of a thermal value representative of the thermal state of the power system and detects an imminent drop of the supply voltage. When such a drop is detected, the processing circuit orders discharging of the capacitor until the voltage at the terminals of the capacitor is representative of the calculated numerical value.

Abstract: A b-bit digital and analog converter of the present invention is relatively simple and non-expensive and monotonic with relatively high differential and integral non-linearities. The converter uses weighed current ratio to achieve decrease the number of current cells to provide a cumulative current which corresponds to the digital value on the input data bus. The converter includes preferably a plurality of upper current cells, at least one unit current cell and at least one lower current cell. The currents produced by the upper, lower and unit current cells have a predetermined weighed current ratio, and the number of the upper, unit and lower current cells are based on the weighed current ratio. Further, the plurality of upper current cells have a prescribed layout, and includes a group of cells where each current cell has reverse layout orientation compared to adjacent cells.

Abstract: A electronic fuse box is provided with an input device such as a keypad with alphanumeric and data entry keys, a central processing unit made from one or more integrated circuits that is communicatively coupled to said keypad as well as a power switch assembly and a metering assembly. Application is achieved by connecting a power source to the electronic fuse box at the power switch assembly. Also, a plurality of external circuits are electrically connected to the electronic fuse box at the metering assembly.

Abstract: A very low cost method of driving the coil of a meter disconnect switch utilizes the 60 Hz signals from an existing power supply rectifier to generate properly phased gate drive signals to SCRS, with only one stage of isolation.

Abstract: A process for the analog/digital conversion of an electric signal as well as a device for implementing the process is described. The process according to the invention provides that the time (T.sub.H, T.sub.L) be determined, which, starting from a voltage (U.sub.X) to be converted is necessary to charge up a RC component (10, 12) to a predetermined reference voltage, for example a switching threshold (S.sub.H, S.sub.L) of a comparator (14) or to discharge it. The device according to the invention provides that a selector switch (13), the comparator (14) as well as a time detector (15) are components of a microprocessor (17), which is wired with the RC component (10, 12) as well as with an input resistor (11) if necessary. The process according to the invention as well as the device according to the invention are particularly easy to realize and are suitable for use especially with a microprocessor (17) which does not have an integrated analog/digital converter.

Abstract: An absolute linear encoder includes an index channel and at least two counter channels. The spacing between markings on the index channel is constant, and the spacing between markings on the first and second channels is predetermined so that the positions of the markings in the first and second channels vary so as to provide a unique signature for each position along the encoder. The linear encoder includes quadrature channels to provide increased resolution and to determine the direction of translation. The encoder is provided with a detector unit to detect positions of the markings in each channel, and a processing unit to calculate an absolute position from the detected marking positions. A method of producing the absolute linear encoder includes selecting spacings for markers in the quadrature, index, first and second channels in order to provide a desired resolution and encoder length.

Abstract: A sampling rate conversion apparatus in which according to an area effect correlation method, an input signal having a first sampling rate K is converted into an output signal having a second sampling rate N. The apparatus includes a first data input device for inputting the first sampling rate and a horizontal synchronous signal or an effective pixel start signal and outputting a multiplication accumulation input data sequence generated by an area effect correlation method, a second data input device for outputting an area effect correlation coefficient generated by the area effect correlation method and the second sampling rate, and a multiplier for multiplying the area effect correlation coefficient and the multiplication accumulation input data device so that the input signal having the first sampling rate K is converted into the output signal having the second sampling rate N.

Abstract: A microprocessor-based control for a solenoid operated device, wherein the microprocessor employs a tri-state output to achieve fast, precise control of the device without overburdening the microprocessor. The system has three selectable control modes: a first control mode in which the solenoid is de-energized, a second control mode in which the solenoid is fully energized, and a third control mode in which the solenoid is pulse-width-modulated. The various control modes are selected by the microprocessor and indicated by the logic level of a tri-state output. In the first and second control modes, indicated by first and second logic levels, the energization state of the solenoid is controlled directly by the microprocessor. In the third control mode, indicated by a third logic level, the energization state of the solenoid is controlled by an external PWM circuit based on PWM commands supplied to the PWM circuit by the microprocessor.