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...During the Civil War, the Confederacy established its own Patent Office which issued 266 patents, a third of which concerned implements of war.
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| Number | Title | Issue Date |
| 4517555 | Smoke detector with remote alarm indication A smoke detector receiving at two input terminals DC power from a remote source not only gives an alarm indication in response to a significant density of smoke, but senses the polarity of DC power at the terminals and generates a secondary signal, distin... | 05/14/1985 |
| 4511890 | Energization indicator for time switch An energization indicator lamp for time switch in which a two-color light emission element which can be switched from either color to the other color is used in place of a conventional energization indicator lamp, and a color of light emitted from the two... | 04/16/1985 |
| 4480221 | Level meter circuit A level meter circuit for displaying the level of an input signal by the use of a number of light emitting diodes. The circuit has a parallel circuit of a plurality of unit circuits each having a diode circuit and a current control transistor connected in... | 10/30/1984 |
| 4470041 | Efficient computer input system for sensing status of high voltage contacts An apparatus is provided for sensing the state of high voltage contact inputs in a process control system. Lower voltage contact closure input modules cooperate with a reference bus and reference bus regulator to reduce the voltage drop across an input mo... | 09/04/1984 |
| 4428020 | Power supply sensing circuitry Power supply sensing circuitry comprises a first comparator for determining whether the power supply potential voltage exceeds by a predetermined amount the voltage required to operate a data processing system connected to the power supply potential, and ... | 01/24/1984 |
| 4422744 | Apparatus for signal transmission and reception between camera and attachment The number of terminals between a camera and an attachment can be reduced by a new combination of camera and attachment. The combination comprises first and second terminals for connecting the attachment to the camera; an information signal generating cir... | 12/27/1983 |
| 4398187 | Pressure monitoring system for a vacuum circuit interrupter A pressure monitoring system for a high-voltage vacuum circuit interrupter including a plurality of capacitors connected in series located outside an evacuated housing and between two metallic end plates each attached to the electrode holder and an arc sh... | 08/09/1983 |
| 4389640 | Apparatus for detecting loss of AC power supply and loss of current Apparatus for detecting loss of AC power supply for an electrical conductor and loss of current through the electrical conductor when the power supply is connected thereto comprises voltage responsive means operable to produce a voltage present signal whe... | 06/21/1983 |
| 4374380 | Automotive electrical network voltage regulation monitoring circuit To provide a visible output indication, for example by an indicator light on a controller supervisory panel of the vehicle, of proper functioning of the voltage regulator power transistor, monitoring circuits are provided which sense the electrical condit... | 02/15/1983 |
| 4369492 | Device for the protection of a converter which converts an impressed D-C current from a current source into an A-C current fed to a load The converter protection device has a number of controlled semiconductor elements. A control unit is connected to the semiconductor elements of the converter for forming firing pulses for the controlled semiconductor elements. Reference blocking intervals... | 01/18/1983 |
| 4360853 | Capacitor voltage and trip coil impedance sensor with high voltage isolation A sensing circuit is disclosed for simultaneously and continuously monitoring the impedance of a trip coil of the type used to actuate synchronously operated circuit breakers, and the charge on a capacitor used to power the trip coil. The sensor comprises... | 11/23/1982 |
| 4345247 | Display system for steady state waves A system for directly displaying steady state waves, such as sound waves, ultrasonic waves, electromagnetic waves, and the like, by instantaneously sampling the amplitude of the waves in a known phase relationship with some other portion of the wave train... | 08/17/1982 |
| 4333119 | Power monitor system Electrical apparatus to monitor electrical three-phase power includes circuitry to protect three-phase equipment from excessive variations in line voltage, phase to phase unbalance, and reverse phase sequencing; to protect personnel against automatic rest... | 06/01/1982 |
| 4318094 | Interface device for remote control An interface device for the remote control of pulse activated, mechanically held relays or master switches by control devices which have a continuous output, such as time clocks, security system devices, and thermostats. The presence of a continuous input... | 03/02/1982 |
| 4309748 | DC/DC Stabilized voltage converter unit In a DC/DC stabilized voltage converting unit having a series circuit including an input filter, a converter stage having a control input and an output filter, the improvement comprising: a control stage having an output connected to the control input; a ... | 01/05/1982 |
| 4306270 | Electrical system monitoring means An electrical system monitor is shown as employing a quad-chip C-MOS integrated circuit for sensing when the voltage of a monitored circuit, monitored sub-circuit, monitored branch circuit or monitored circuit portion deviates, by a preselected magnitude,... | 12/15/1981 |
| 4306176 | Operation indicator for automatic flash device An operation indicator for an automatic flashing device comprising a first indication means which visually indicates a reaching to a predetermined voltage of main capacitor and readiness for proper completion of flashing of an automatic light adjusting, a... | 12/15/1981 |
| 4291302 | Lamp monitoring circuits A circuit for monitoring the voltage across a sensing resistor in series with a load, wherein two reference currents are generated, each dependent both on temperature and on the voltage on a power supply line, which voltage is also temperature-dependent a... | 09/22/1981 |
| 4247849 | Constant current voltage sensing circuit A current limiting voltage sensing circuit especially suited as an annunciator input circuit is disclosed. It includes a radiation emitting device circuit, a current limiting circuit for maintaining the current supplied to the voltage sensing circuit at a... | 01/27/1981 |
| 4197484 | Electronic flash device with voltage display An electronic flash device comprising a DC-DC converter circuit which converts a low voltage DC source to a high voltage DC current for charging a main discharge capacitor, a flash discharge tube which is adapted to flash by means of the energy stored in ... | 04/08/1980 |
| 4163924 | Circuit for turning on a charging-completion indicator separate from a flash unit In a flash unit, wherein completion of the charging of a main capacitor from a DC-DC converter is indicated by a first indicator connected to the converter by a first voltage dividing circuit, there is provided a second voltage dividing circuit connected ... | 08/07/1979 |
| 4162479 | Automobile burglar alarm with battery voltage sensing means An automobile burglar alarm including a battery voltage level sensor to be connected to the positive terminal of the automobile battery for providing an output signal level indicating the battery voltage level and responsive to reduction in the automobile... | 07/24/1979 |
| 4145637 | Capacitor charge indicator in an electronic photoflash A glow lamp for indicating charged readiness of a flash apparatus is provided with a predetermined burning voltage corresponding to a specific charge voltage of the storage capacitor for the flash circuit, and the ignition voltage for the glow lamp is app... | 03/20/1979 |
| 4143410 | Electric power system control utilizing low level signals and miniature gage wiring Control circuit system wherein low level signals are delivered through small (miniature) gauge control conductors to remote control circuit breakers to control connection of load devices to load bus through use of solid state circuitry. Such control may b... | 03/06/1979 |
| 4074515 | Electronic timepiece with battery life display In a digital electronic timepiece, at least one of the digital displays changes color to indicate that the battery is nearing exhaustion. The display is made up of two sets of display elements, for example LEDs, disposed closely adjacent alongside one ano... | 02/21/1978 |
| 4039928 | Electrical operating circuit having semiconductor device junction temperature monitoring An operating circuit for a semiconductor switch device of the type that passes electrical current from a source to an electrical load by forward biasing of the semiconductor's control terminal includes a resistance bridge network having in an arm thereof ... | 08/02/1977 |
| 4021793 | Detector device for converting A.C. inputs to an D.C. output and a system for using the same An input detection circuit to provide a D.C. output signal of a selected value upon receipt of an input A.C. signal of a given value on an input line. The detector circuit includes a NORTON type current responsive operational amplifier having an inverted ... | 05/03/1977 |
| 3999126 | Test device for simultaneously displaying the level of logic signals in a plurality of circuits A test clip suitable for connection to a plurality of terminals at which appear respective logic signals representing those occurring in logic circuits provides an indication of the logic level of such signals. The circuit for effecting such indication is... | 12/21/1976 |
| 3991367 | Detection of potential on high-voltage transmission lines A suspension insulator used on the tower of a high-voltage transmission line has a capacitive voltage dividing pickup plate placed thereon to capacitively pick up a low-power indication of the potential carried by the line. In order to detect the potentia... | 11/09/1976 |
| 3964039 | Luminescent solid state status indicators A luminescent solid state status indicator including at least first and second light emitting diodes of different colors which may be mounted on a single header. One side of each of the diodes is connected in common to one side of a source of energizing v... | 06/15/1976 |
| 3940679 | Nickel-cadmium battery monitor The nickel-cadmium battery monitor is provided with sensors for measuring the battery temperature, the battery voltage and the magnitude of the current being charged to the battery, each of the sensors generating a sensor signal voltage that varies direct... | 02/24/1976 |
| 3938144 | Digital multiplexing system remote scanning of a plurality of monitoring points A digital start-stop multiplexing system including a sender which sequentially scans a plurality of monitoring points and generates a train of digital pulses coded to represent information provided at the monitoring points for transmission over a transmis... | 02/10/1976 |
| 3934188 | Self-testing battery discharge indicator The voltage of a battery connected to a load is monitored to provide a continuous instantaneous indication of the voltage level of the battery and to provide an indication that the battery voltage has fallen to some critical level. Means are provided for ... | 01/20/1976 |
