Alps Electric Co., Ltd.

Toshihiko Kawata

Ken Mizuta

Ken Shibazaki

Yukio Miura

Hidetaka Numata

Kazuaki Fukuda

Shigetoshi Kagomiya

An object of the present invention is to provide a waveform shaping circuit for producing a trapezoidal pulse whose leading edge and trailing edge have the same slope and not inducing and radiating harmonic components under any conditions. A waveform shaping circuit comprises a common-emitter transistor 1, a first resistor 2 and second resistor 3 connected in series between a signal input terminal 9 and the base of the transistor 1, a third resistor and first capacitor 5 connected in parallel between a node a between the first resistor 2 and second resistor 2 and a ground, a feedback capacitor 6 connected between the collector of the transistor 1 and the node 1, and a collector load resistor 7 connected in series with the collector of the transistor 1. The waveform of a pulse to be applied to the signal input terminal 9 is reshaped to produce a trapezoidal pulse whose leading edge and trailing edge have a substantially equal slope, and then the trapezoidal pulse is led through a signal output terminal 10. When the waveform shaping circuit is employed in a transmission unit in a communication block in a door control unit included in an on-vehicle multiplex communication network system, the magnitude of induction and radiation of unwanted harmonic components can be reduced drastically.

Waveform shaping circuit

A multiplex communication system in which operational data is transmitted to a bus line at different frequencies according to the necessity of transmission. Further, transmitting and receiving nodes are identified without having to include address data with the transmitted message data, thereby avoiding a time lag in control processing of vehicle-mounted equipment. In accordance with a first embodiment, a plurality of data signals which are transmitted via a bus line from a plurality of node devices, to at least one of a plurality of end node devices to be controlled, are divided into a plurality of degrees according to the necessity of transmission. Operational date signals falling into the greatest degree of transmission necessity are transmitted once in every cycle, while data signals falling into the lesser degrees of transmission necessity are transmitted once in every few cycles according to the degree of necessity. In a second embodiment, one of a plurality of node devices connected to a bus line serves as a master node device and sets the transmission cycle of message data transmitted onto the bus line. This cycle is set so as not to cause a time lag in data processing executed by the respective node devices. Each time interval between the start pulses is divided into a plurality of time slots. The time slots have been allocated to the individual node devices so that message data can be transmitted from the respective devices in the associated time slots.

Communication system using time division multiplex signal transmission

An on-car motor driving apparatus is equipped with a motor for moving a moving unit such as a window of a motor car, a motor driving controller which controls the revolution, stop, and rotational direction of the motor, and a current measuring and comparing device which measures the variation in current per unit time of the motor and compares the measured variation in current with a preset value. The on-car motor driving apparatus stops the revolution of the motor and/or reverses the rotational direction of the motor through the motor driving controller. The apparatus is further equipped with a voltage measuring device for measuring motor driving voltage and a voltage-based time setting device which changes the length of the unit time in accordance with the driving voltage value measured by the voltage measuring device. Line voltage is supplied to a differential amplifier only when the line voltage is supplied to the motor.

On-car motor driving apparatus and self-diagnosing and selective driving

An apparatus for detecting and controlling the rotational position of a motor without using a high-priced component and without requiring special software processing. The apparatus includes a motor rotation control section for selectively connecting a power source to the motor to rotate the motor into a predetermined position, a potentiometer mechanically linked to a shaft of the motor to read the absolute rotational position of the motor, an astable multivibrator for generating output pulses having a duty ratio corresponding to the position read by the potentiometer, and a control signal generation section for supplying a control signal corresponding to the duty ratio of the output pulses to the motor rotation control section to control the rotational position of the motor.

Apparatus for detecting and controlling the rotational position of a

In a load controlling apparatus used in, for instance, an automobile, equipped with a mulfunction diagnostic circuit, there are employed:

Loading controlling apparatus

A blower motor drive control circuit is configured to maintain a fixed value of motor driving current to maintain a constant amount of air supply from an air conditioner regardless of changes in the amount of intake air.

Motor drive control circuit

A load controller for an automobile comprising power lines of a pair of conducive members insulated as power supply line and ground line wired in an automotive room, a control unit including a switch circuit connected to the power line near a load for supplying power from the power line through the control unit to the load, thereby controlling the control unit by a control signal outputted from a microcomputer. Thus, the load controller can alleviate a labor of wirings of the power lines.

Load controller for automobile

A lamp illumination adjusting apparatus for automobiles comprises a reference triangular wave generator, an adjusting voltage setting circuit, a comparator to compare the reference triangular signal with the adjusting voltage and to output comparison signal, a driver circuit including a MOS field effect transistor which is controlled directly by the comparison signal, and a lamp which is connected in series to the driver circuit and interposed between a power source terminal and the ground.

Lamp illumination adjusting apparatus

An output stage control circuit comprises an output driving means connected to a load for driving the same, a control means for taking out detection signals corresponding to signals flowing to the load and supplying analog control signals to the output driving means and a reference signal supply means for supplying reference signals to the control means, in which the analog control signals are generated depending on the detection signals and the reference signal, and the load is driven in an analogous manner by the output driving means depending on the analog control signals. The output stage control circuit can continuously supply the current to the load thereby operating the load stably with less occurrence of noises and stably for a long period of time.

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Sendai, Japan

Toshihiko Kawata