摘要:
A communication apparatus in an airbag system includes an airbag ECU as a master unit, sets of communication lines and slave sensor devices. The slave sensor devices are respectively connected to the airbag ECU through the set of communication lines. The airbag ECU transmits data transmission request commands to the respective sets of communication lines at timings which are different from each other. Thus, transmission timings in the respective sets of communication lines are prevented from being synchronized, and noise which develops in consequence of the data communications between the master unit and the slave sensor devices can be reduced.
摘要:
A communication apparatus in an airbag system includes an airbag ECU as a master unit, sets of communication lines and slave sensor devices. The slave sensor devices are respectively connected to the airbag ECU through the set of communication lines. The airbag ECU transmits data transmission request commands to the respective sets of communication lines at timings which are different from each other. Thus, transmission timings in the respective sets of communication lines are prevented from being synchronized, and noise which develops in consequence of the data communications between the master unit and the slave sensor devices can be reduced.
摘要:
In a voltage booster circuit, a switching transistor turns on and off a flow of an electric current in a booster coil thereby to boost a voltage supplied form a d.c. power source. A back-up circuit is connected to the booster coil to store the boosted voltage as an output voltage. A current detection circuit detects an electric current flowing in the switching transistor and turns off the switching transistor, when the detected current reaches a predetermined level. An off-period control circuit variably controls an off-period of the switching transistor after the switching transistor is turned off. The off-period control circuit varies the off-period in accordance with a voltage difference between the output voltage and an upper limit threshold voltage. The off-period of the switching transistor is increased as the output voltage increases toward the upper limit threshold voltage
摘要:
An occupant protection system for an automotive vehicle is provided which includes a pair of squibs for activating a pair of occupant protection units such as an airbag unit and a pretensioner for a seat belt, a backup capacitor, and a switching circuit. The switching circuit serves to allow the electric power stored in the backup capacitor to be supplied to at least one of the occupant protection units upon occurrence of a collision of the vehicle with another object when a sufficient power is not supplied from the power source to the squibs or when a line connected to the power source is broken by the collision of the vehicle.
摘要:
A battery voltage regulator for a vehicle charging system includes a voltage control circuit for controlling a battery terminal voltage and an external terminal connected to the positive terminal of a battery through the series combination of a charge lamp and an ignition switch. The regulator is at least composed of a charge lamp drive circuit responsive to a generation output of an alternator in order to energize the charge lamp, a power supply circuit responsive to the potential at the above mentioned external terminal to supply operational power to the voltage control circuit, and a malfunction-preventing circuit connected between the above mentioned external terminal and ground. The malfunction-preventing circuit prevents the power supply circuit from operating by disturbances such as leakage current flowing into the regulator through the external terminal. The regulator may further include a backup circuit responsive to the generation output of the alternator to separately supply operational power to the regulator circuit irrespective of the operation of the power supply circuit when the generation output reaches a voltage value which is higher than the above mentioned potential value at the external terminal by which the power supply circuit is energized, whereby the battery terminal voltage may be continuously maintained constant to a desired level even when a break in the charge lamp conductor has occurred.
摘要:
A voltage regulating system for an automotive vehicle having a switching transistor connected to a field winding of an alternating current generator and a regulator for comparing a battery voltage with a reference value and for driving the transistor into a conductive state when the battery voltage is lower than the reference value. A current limiting circuit is provided for limiting the field current when the switching transistor is going to be driven into the conductive state over a predetermined interval, so that a maximum charging current can be obtained and an unfavorable heating of the switching transistor can be avoided.
摘要:
A battery voltage regulating system for an automotive vehicle, wherein a field current flowing through a field coil of an alternator is periodically cut off irrespectively of whether a battery voltage is higher or lower than a reference voltage, and a conduction ratio of the field current is controlled in accordance with a difference between the battery voltage and the reference voltage. The reference voltage is changed in response to an increase or decrease of the conduction ratio, so that a battery voltage is prevented from decreasing when the conduction ratio is increased.
摘要:
A battery charging control system for automobile, wherein a voltage regulator for regulating the output voltage of an AC generator for charging the automobile battery is controlled by detecting changes of the output voltage. When the output voltage of the generator changing with ripples is reduced with an increase of load current, the minimum value of the output voltage is detected, while when the output voltage increases with an increase of the generator rotational speed, an average value of the output voltage is detected. In accordance with these values, the voltage regulator is controlled to compensate for the changes of the output voltage of the generator.
摘要:
In a voltage booster circuit, a switching transistor turns on and off a flow of an electric current in a booster coil thereby to boost a voltage supplied form a d.c. power source. A back-up circuit is connected to the booster coil to store the boosted voltage as an output voltage. A current detection circuit detects an electric current flowing in the switching transistor and turns off the switching transistor, when the detected current reaches a predetermined level. An off-period control circuit variably controls an off-period of the switching transistor after the switching transistor is turned off. The off-period control circuit varies the off-period in accordance with a voltage difference between the output voltage and an upper limit threshold voltage. The off-period of the switching transistor is increased as the output voltage increases toward the upper limit threshold voltage
摘要:
An automotive occupant restraint system with a simple and compact energy reserve circuit is provided which includes an occupant restraint mechanism, a step-up circuit, a backup capacitor, a crash monitor, a firing circuit, and a switching circuit. The step-up circuit steps up the voltage supplied from a battery to charge the backup capacitor up to a given voltage level. The crash monitor monitors a vehicle crash to provide a crash signal. The firing circuit is responsive to the crash signal to activate the occupant restraint mechanism. The switching circuit selects between a first and a second power supply mode. The first power supply mode is established to block communication between the backup capacitor and the crash monitor when a sufficient amount of electrical energy of the battery is supplied to the crash monitor, while the second power supply mode is established to communicate the backup capacitor to the crash monitor when the electrical energy supplied from the battery drops below a given voltage level to supply electrical energy stored in the backup capacitor to the crash monitor.