摘要:
A load drive device is provided for outputting a control signal to a driving transistor and for driving a load by switching, the driving transistor and the load being connected in series between a direct current power source and ground. The load drive device includes a reverse connection protection unit which is provided in a line leading from a negative side of the direct current power source, and which blocks a current flowing therethrough when the direct current power source is connected in reverse. A failure detection is performed by a failure detection process by monitoring a change of a current flowing via the reverse connection protection unit during the driving transistor is in a conduction state.
摘要:
In a control apparatus for a motor, which rotates a fan, a semiconductor device is connected to the motor in series to drive the motor. An analog driver circuit drives the semiconductor device with an analog voltage. A PWM control circuit drives the semiconductor device with a PWM signal of a frequency of less than several tens. A switching control circuit selects the analog driver circuit and the PWM control circuit when the motor is to be rotated at speeds lower and higher than a predetermined speed, respectively.
摘要:
In a control apparatus for a motor, which rotates a fan, a semiconductor device is connected to the motor in series to drive the motor. An analog driver circuit drives the semiconductor device with an analog voltage. A PWM control circuit drives the semiconductor device with a PWM signal of a frequency of less than several tens. A switching control circuit selects the analog driver circuit and the PWM control circuit when the motor is to be rotated at speeds lower and higher than a predetermined speed, respectively.
摘要:
A cooling fan control circuit drives a brushless motor to rotate a cooling fan to cool a condenser and a radiator mounted on a vehicle when a drive signal is activated. In a situation where the brushless motor rotates at a rotational speed equal to or higher than a predetermined value by flowing air in a situation that the drive signal is not activated and a charge state signal indicating that a battery is not in a fully charged state, the control circuit turns off MOSFETs in upper arms of an inverter circuit and simultaneously, synchronously switches MOSFETs in lower arms of the inverter circuit. With this configuration, an electric energy generated by the flowing air is stored from the brushless motor to a battery.
摘要:
An error such as disconnection or short on the current path from said dc power supply to a switching element via the dc motor is detected by judging whether variation in a voltage at a junction point between the dc motor and the switching element tracks variation in the pulse width modulation signal for the switching element. If this is false for a predetermined interval, this apparatus judges there is the error. The error is judged by variation in a voltage at a junction point between the dc motor and the switching element tracks variation in the pulse width modulation signal, so that though the dc motor is driven by a fan for cooling the engine of a motor vehicle because of wind due to traveling of a motor vehicle, the error can be judged accurately.
摘要:
A vehicle cooling system including a motor control apparatus that controls operation of a system motor when a cooling fan driven by the motor locks due to foreign matter interference or freezing. When motor input current is detected to be overcurrent, the controller limits the current flow. When current flowing to the electric motor is detected to be overcurrent and ambient air temperature is at or above a predetermined temperature, the controller stops energization of the motor. Thus, when the cooling fan freezes and locks, energization of the motor is maintained until ambient air temperature reaches or exceeds the predetermined temperature. Therefore, when the frozen-locked state is eliminated due to a subsequent temperature rise, an ordinary operating state can again be obtained without the controller subsequently detecting surge current, generated as a result of the motor being re-started from a fully stopped state, as overcurrent and therefore incorrectly stopping motor energization. Additionally, when locking occurs due to foreign matter interfering with fan rotation, an overcurrent state is detected even when ambient air temperature is at or above the predetermined temperature, and motor energization is immediately stopped.
摘要:
The present invention provides a manufacturing method of a flat-panel display unit and a carrier therefor which make it unnecessary to implement alignment in each step, except for alignment which require higher precision, by performing the alignment in advance in the pre-stage of a series of steps. The present invention also provides a manufacturing method of a flat-panel display unit which allows alignment with accuracy of about 50 to 100 .mu.m to be performed simply, reliably and quickly. According to the inventive manufacturing method, a display panel is mounted non-shiftably on the carrier and while being mounted thereon, is then carried between processing machines and is processed by the processing machines. In mounting the display panel on the carrier, it is aligned with the carrier in advance by visually aligning alignment marks thereof. In processing it by the processing machine, the carrier and the processing machine are put into a predetermined state in which they are aligned and thereby, the display panel is put into a state in which it is aligned with the processing machine.
摘要:
A strut aligning fixture capable of improving misregistration of struts arranged between two glass plates for a vacuum glass envelope to hold the glass plates spaced from each other at a predetermined interval. An alignment plate is formed of a first alignment plate member of a small thickness and a second alignment plate member of a large thickness by lamination. The first alignment plate member is provided with strut holes, which can be formed with high accuracy because of a reduced thickness of the first alignment plate member. The alignment plate is used as a fixture for arranging the struts in the vacuum glass envelope while minimizing misregistration of the struts.