Hitachi, Ltd.

Hitachi Car Engineering Co., Ltd.

Hitachi Automotive Engineering Co., Ltd.

Other

Hitachi Kiden Kogyo, Ltd.

Naoyuki Takahashi

Keiichi Mashino

Sakae Hikita

Atsushi Kanke

Yuuji Maeda

Shouju Masumoto

Shuuichi Kokubun

Syouju Masumoto

Katsuji Marumoto

Masakatsu Fujishita

Yoshiaki Honda

Takahisa Nitta

Seiji Watanabe

Masanori Tsuchiya

Sakae Ishida

Ichiro Fukuwatari

Yoshio Saito

Noritaka Sekiya

When a MOS transistor is turned off, a forward current flows into a diode connected to the MOS transistor. When the MOS transistor is conducted, a reverse bias is applied to the diode. When the MOS transistor is turned on during the reverse recovery time of the diode, a short-circuit current flows into the MOS transistor, the diode, and a battery connected in series with the diode and the MOS transistor. In this case, an overcurrent flows through the wiring of the battery momentarily, and electromagnetic wave generates from the wiring. Accordingly, noise caused by the electromagnetic wave is generated in an antenna to a radio receiver. The drain current of the MOS transistor is gradually increased by a delay circuit, and the MOS transistor is shifted from a completely turned-off state to a completely turned-on state with a time period longer than a reverse recovery time of the diode. Consequently, no reverse current flows through the diode. Therefore, a short-circuit current is prevented from flowing through the battery, the diode, and the transistor, and no noise is generated in the receiver.

Driving apparatus for power MOS transistor

A control device for a motor vehicle electric generator takes into account the relationship between field currents flowing through field windings of charging generators having different generation powers and output currents. The field current is increased once and instantly at the time of loading but prior to suppressing the increasing speed of the field current. The amount of the increase of the field current is controlled to be proportional to the field current before the loading. The control device according to the invention can be used for charging generators having different power generation capacities, and the battery voltage drops at the moment when switching in a motor vehicle electric load are reduced to substantially the same level.

Control device for motor vehicle use charging generator

A short protection circuit is provided to periodically supply a reset pulse, turns on an electric power element only during the period of the reset pulse, and decide the presence and absence of a short circuit under the condition that the electric power transistor is forced to turn off when a field coil is short-circuited. In this short portection circuit, while the field coil is short-circuit, the reset pulse cycle is reduced, and hence the number of times the resetting is made per unit time is reduced, thus preventing the electric power element from generating excessive heat when the field coil is short-circuited.

Charging generator having a short protection circuit

A regulator for an alternator installed in a vehicle has a switching circuit in which a field current limiting transistor interruptibly controls a flow of current to a field coil of the alternator. A battery output voltage detection terminal is connected to the battery, and an alternator output voltage terminal is connected to the alternator. A diode connected to the battery output voltage detection terminal has a reverse recovery time of 20 ns-20 .mu.s, and a resistor is connected between the diode and the alternator output voltage terminal. A control circuit controls the switching circuit, in order to regulate the voltage at a connection point of the diode and the resistor so as to keep the voltage constant, and an alarm generating circuit illuminates a charge indicator lamp if the voltage at a junction of said diode and said resistor exceeds a reference voltage.

Regulator for an alternator of a vehicle

A power source system for a vehecle is disclosed. The system has a generator driven by an internal combustion engine, a control equipment for controlling the generator, a battery, a heater which is heated by the generated output of the temperature detecting means for detecting generator, and a temperature of the heater. The system has a switch between the heater and between the generator and the generator and the battery. The heater and the battery are connected in parallel to each other.

Power source system for a vehicle

A control device for a battery charging AC generator for a motor vehicle including a power transistor connected in series with a field winding of the AC generator for performing switching control of a current flowing through the field winding. A voltage deviation circuit detects a deviation of the battery voltage from a reference voltage; and a PWM signal generating circuit is responsive to a voltage deviation signal from the voltage deviation circuit for turning the power transister on and off a resistor connected in series with the power transistor detects a current flowing through the field winding; and a current limiting circuit generates a turn off signal for the power transistor when the detected current is determined to have exceeded a reference current. A latch circuit operates in response to a clock signal from the PWM signal generating circuit to limit the frequency of turning on and off of the power transistor to below 1 KHz.

Control device for battery charging AC generator used in motor vehicle

Electric generator control for a motor vehicle in which the field current IF provided to the field coil of the generator is variable between two values in response to variations in the load applied to the battery. The output voltage of the battery is compared to a predetermined reference value, and a signal representing the difference is supplied to a voltage divider and to an integrator circuit. The outputs of the voltage divider and the integrator are then provided to respective, comparators. A reference signal provided by a time variable signal generator is supplied to both comparators, the respective outputs of which are connected to the inputs of an AND gate which controls a gating element which in turn controls the field current. In the case of a sudden increase in load applied to the battery, the output of the integrator responds more slowly than the voltage divider, which tracks the difference signal instantaneously, and the operation of the power switch is controlled by the output of the integrator circuit.

Charging generator control for vehicles

A conveyor means for transporting precision parts is divided into a plurality of block units and compressed air is supplied selectively to each block unit where a transporting pallet is present so as to reduce consumption of compressed air to the minimum. Also, it ensures high carrying efficiency because of its slow starting and slow stopping without reducing the speed during running.

Growing community of inventors

Mito, Japan

Naoyuki Takahashi