Abstract: Method and apparatus for controlling the output frequency of an alternator by maintaining a relatively constant speed of rotation of the alternator rotor are disclosed. The rotor includes an annular stator and a rotor rotatably mounted within. In one embodiment the stator winding is comprised of a plurality of discrete polyphase windings positioned within discrete annular segments of the stator. When the actual rotor speed is below the desired speed, selected stator units are de-energized to decrease the strength of the stator magnetic field, thereby permitting the rotor speed to increase. When the actual rotor speed is greater than the desired speed, selected stator units are energized to increase the strength of the stator magnetic field, thereby exerting a braking force on the rotor to slow it down. In another embodiment each phase of the polyphase stator winding includes a plurality of inductor coils.

Abstract: An improved portable battery charger (10) for boosting and charging automotive-type batteries. The battery charger (10) comprises rectifier means (34), an automotive-type battery (20), and an air compressor (24) powered by the battery (20) received within a charger housing (12). Positive and negative charging cables (30 and 28, respectively) are retractably received within first and second cable housings (14 and 16), respectively. The first and second cable housings are positioned adjacent oppositely disposed external walls of the charger housing (12) and are dimensioned such that the positive and negative charging clamps (76 and 70, respectively) may be slidably positioned over saddle notches (72) defined by the cable housings when the charging cables are fully retracted into the cable housings whereby the charging clamps (76 and 70) are physically isolated from each other by the charger housing 12, thereby preventing accidental contact between the clamps.

Abstract: A safety device is wired in series with selected accessories in a wiring circuit for a vehicle. The safety device of the present invention determines the state of charge of the battery as a function of the rate of discharge of the battery. When the state of charge falls below preset values, the device activates a switch which disconnects the battery from the vehicle wiring circuit in order to save sufficient energy for engine ignition. In another embodiment, a programmed microprocessor activates electronic switches to sequentially disconnect banks of accessories from the battery.

Abstract: A Marx high voltage generator with a fast rise time. Photoconductive semiconductor switches are sequentially triggered by a single laser via fiber optic bundles of different lengths. The switches serve to series connect a group of charged capacitors. Output is taken from the last capacitor which receives the voltage accumulated on all of the previous capacitors. Proper timing of the activation of each switch produces a fast rise time.

Abstract: Externally charged electrodes of an electrostatic generator induce charges of opposite polarity on segments of a pair of confronting stators by means of electric fields within which a pair of rotors are confined during rotation to vary the charge binding field linkages between confronting rotors and stators by a shielding action of the rotors in a plane perpendicular to the field flux. A high electric potential difference induced between the stators resulting from such rotation of the rotors, is transformed by an output circuit into a reduced DC voltage applied to a load with a correspondingly increase current conducted therethrough.

Abstract: The present invention is an electrical circuit for regulating the average current through and the voltage across a load, such as a rechargeable battery. The circuit includes at least one semiconductor switching device connected in series with the load for controlling the current through the load. A current control loop is provided in the circuit to maintain the average current through the load at a constant level despite changes in the resistance of the load. Also provided is a voltage control loop which acts to limit the voltage across the load to a value below a predetermined voltage level.

Abstract: In a marine propulsion system including an internal combustion engine driving a voltage generator (14) supplying system voltage (line 26) which is supplied to ignition circuitry (10) providing spark ignition for running the engine in normal operation, overvoltage protection is provided for both the voltage generator regulator (12) and the ignition circuitry. If sensed system voltage is below a given threshold (V.sub.T), normal operation of the engine is continued. If sensed system voltage is above the given threshold, engine speed is reduced to reduce the generated voltage.

Abstract: A testing and battery exercising method and control for an emergency lighting unit, which is activated by a drop in voltage of a primary power source, provides for frequency testing of the unit by utilizing a control unit in conjunction with an infrared sensor and photocell to control a voltage reduction simulation device. The control device includes a means for sensing a change in a heat pattern over a pre-determined illumination area, a means for sensing ambient light in the illumination area, a means for simulating a reduction in voltage of a primary power line and control a unit which causes a reduction in voltage to be simulated to turn on the emergency lighting unit only when a change in the heat pattern and the illumination area is detected while the ambient light over the illumination area is below a threshold value.

Abstract: A battery charger includes a first charger for providing a first battery charging current and a second charger for providing a second battery charging current. A switch is provided for manually actuating the second charger. A timer times the second charger cycle. The timer is used to initiate the discontinuation of operation of the second charger. When the second charger is operating, the timer is inhibited from being reset. When the first charger discontinues supplying a charging current, the battery charger is conditioned to again permit actuation of the switch to reset the timer and allow operation of the second charger.

Abstract: A self-excited brushless alternator having a rotating field winding excited by an alternating current exciter whose rotating armature rotates with the rotating field winding and is permanently connected to the field winding via a field rectifier also mounted to rotate with the field winding. The exciter has an exciter stator primary winding and a rotary exciter secondary winding connected via a rotray field rectifier to the rotary main field winding of the alternator. The primary excitation for the exciter is derived, via magnetic coupling, from a rotary auxiliary magnetic field produced by a feedback winding in series with the main field winding and rotating herewith. A common magnetic circuit couples the rotary feedback winding with an auxiliary stator secondary winding and the exciter primary and secondary windings.

Abstract: A vehicle battery system includes a battery for providing electric current to a starter of the vehicle through a first electrical cable, and for providing and receiving electric current to and from, respectively, a remote battery through a second electrical cable for recharging a certain one of the batteries. A casing of the battery has a pair of spaced electrodes incorporated therein which establish electrical contact with an electrolyte solution contained in the casing. A pair of universal plugs is embedded in the casing and is electrically connected to the electrodes by electrical conductors also embedded in the casing. Each universal plug includes a prong and a receptacle so that the plugs are engageable with other similar universal plugs in a single orientation for maintaining proper electrical polarity therebetween. A universal plug is attached to one end of both the first and second electrical cables for engaging the plugs of the system battery.

Abstract: A constant current battery charger includes a bucking regulator comprising a power switch transistor, a diode, an inductor and a voltage sensitive switch with adjustable delay for controlling the power switch transistor. The hysteresis or delay is obtained with a Schmitt trigger and the effect is a stable pulse width modulator in which the duty cycle of the power switch transistor is varied. A current foldback circuit includes a zener diode coupled to the battery for changing the sensitivity of the switch to substantially reduce charging current when a battery voltage corresponding to a fully charged state is reached.

Abstract: A computer power system comprises an AC-to-DC power supply for providing DC power to the computer during the presence of AC line power and a backup power supply for providing DC power from batteries directly to the DC operated components of the computer system, completely bypassing the AC to DC power supply, when AC line voltage is absent or low.

Abstract: The invention relates to a device for supplying electricity at overvoltage in an automobile.Automobile circuits comprise a main circuit (1) and an auxiliary circuit (2) requiring to be temporarily supplied at overvoltage. The main circuit is normally supplied by a battery (3) fed by an alternator (4) of which the excitation circuit is regulated by a regulator (5). In accordance with the invention, the device includes commutation means (6) controlled from the stator output of the alternator on the auxiliary load (2), the excitation of the alternator (4) following this commutation being taken via the regulator (5) to a sufficient value as a function of the state of the engine (M) for assuring a temporary supply state of the auxiliary circuits (2) at overvoltages and at reduced current.Application to supply of electric circuits of automobiles or the like.

Abstract: A recharging network for a solar powered construction light, including a solar powered battery, that recharges a storage battery at a constant rate and can be selectively operated to burn the light continuously to produce a continuous light or to burn intermittently to provide a flashing light. The network allows a solar cell to recharge the storage battery when sunlight is impinging upon the solar cell to provide virtually maintenance free and long term operation of the construction light during the dark or twilight hours when construction lights are commonly employed to warn motorists of road hazards.

Abstract: Integrated circuit voltage regulator (60; 81; 91) is provided for use in a battery charging system (10) for providing excitation current to a field coil (13) of an alternator (11). The integrated circuit voltage regulator includes a transistor (70) which is selectively switched on and off to implement the prior art diesel diode (26) functions of providing initial field coil excitation current while preventing undesired current flow from an alternator voltage supply terminal (20) during subsequent field coil excitation current. The transistor (70) is provided as part of an integrated circuit and, therefore, eliminates the need for a diesel diode (26) external to the integrated circuit. In addition, use of the switched transistor (70) minimizes voltage drop loss when providing initial field excitation current. Constructing the transistor (70) as a PNP vertical substrate transistor minimizes integrated circuit area and simplifies integrated circuit topology.

Abstract: Method for charging Ni-Cd batteries with a repetitive and alternating sequence of direct current charging and discharging periods. Steep current pulses are superimposed on the respective direct currents which have a sense equal to that of the direct current and intensity exceeding respective predetermined levels. Owing to the effects of such alternating and repetitive current pulses the surface distribution of the electrodes will change after some time and the electrode surface gradually become homogeneous.The periodically repetitive steep current pulses can be used during the whole charging process and they have beneficial effects for the charging of new batteries as well.The current changes at the beginning of the respective periods should be at least seven times as high as one tenth of the ampere-hour capacity of the battery.

Abstract: This invention relates to a method for charging a rechargeable battery especially lead-acid batteries. In this method, the open circuit voltage of the battery is measured and the minimum number of cells is estimated from this value. The battery is then charged at any charge rate and at a constant current until the battery voltage is substantially equal to the estimated number of cells multiplied by a voltage which is characteristic of the battery, and thereafter the battery is charged at any charge rate and at the aforesaid battery voltage until the current decreases to some predetermined value. The foregoing steps are repeated alternatively until a constant or substantially constant value for the estimate number of cells is obtained. Thereafter, the battery is charged at a voltage equal to the number of cells multiplied by the characteristic voltage of the battery until the current reaches a predetermined value and then the battery is charged at some predetermined current for a predetermined period of time.

Abstract: A current supplying device is provided and connectable across the positive and negative terminals of a battery to supply a direct current to the positive terminal. The device includes an alternating current (AC) to direct current (DC) converter for generating a direct current from an AC power source. A pair of circuits biased to inoperative conditions are coupled to the converter and separately actuable to an operative condition to supply the direct current to one of the battery terminals. A polarity detector senses the polarity of the battery terminals and provides siganls to a plurality of switches which actuate one of the circuits to the operative condition so that the direct current is always supplied to the positive terminal of the battery. Current overload protection is also provided for protecting the polarity detector and inhibiting the operation of the switches in order to return the one circuit to the inoperative condition in the event of unsafe current flow in the one circuit.

Abstract: A battery charger has a recess for accommodating a battery pack, and charging electrodes projecting into the recess. The battery pack is charged when the battery pack is inserted into the recess and battery electrodes of the battery pack are brought into contact with the charging electrodes. In an improvement of the battery charger, the recess has portions of different shapes corresponding to respective shapes of a plurality of different battery packs for accommodating the different battery packs, and the charging electrodes have portions projecting into the recess portions respectively.