Aisin Seiki Kabushiki Kaisha

Aisin Seiki Company, Ltd.

Nobuyoshi Nagura

Taneichi Kawai

Koji Nishida

Shigemitsu Hamajima

Tsuneo Hida

Hiroki Oka

Mitsuo Yamamoto

Keiichi Yamamoto

Norishige Yoshikawa

Takaki Manabe

A pulse shaper is disclosed which shapes a vehicle speed signal developed by a tachometer and pulsating with a frequency which is proportional to a vehicle speed into a rectangular wave pulse. A reference potential line is biased above a common potential. The vehicle speed signal has its level clamped to a range from 0.6 V below to 0.6 V above the potential of the reference potential line. A first IC comparator digitizes the clamped speed signal into a binary form around the potential of the reference potential line. When the reference potential line becomes short-circuited to the common potential. The clamped vehicle speed signal which is applied to the inverting input of the first comparator reduces below the common potential, giving rise to the likelihood of an erroneous pulse. A second IC comparator then detects a reduction in the potential of the reference potential line to constrain the output of the first comparator to an L level, preventing an erroneous pulse from being delivered.

Binary digitizer circuit for voltages developed across induction coil

A vehicle speed detecting device utilizes two vehicle speed pulse generators, a vehicle speed memory device, pulse counters, abnormality detectors, pulse signal transfer devices and an alarm device which are all integrated into the electronic control circuit of a micro-processor through two sets of signal processing devices. The detecting device not only indicates the speed of the vehicle but also detects abnormalities in either of the vehicle speed pulse generators and provides an appropriate alarm.

Vehicle speed detecting device

An automatic transmission control apparatus detects an abrupt loss of vehicle speed from the speed sensor due to failure of the speed sensor. The control apparatus detects a condition of the brake operation so that the abrupt loss of the vehicle speed is detected for transmission control purposes when the brake is under non-operating conditions.

Brake responsive automatic transmission control apparatus

An automatic transmission control apparatus detects an abrupt loss of signal from the speed sensor due to failure of the speed sensor and shifts the automatic transmission to a higher gear ratio. The control apparatus detects the engine rotation and the position of the shift lever so that when the engine rotation is under a predetermined level the control apparatus allows the automatic transmission to be shifted by the position of the shift lever.

Automatic transmission control apparatus

Digital data is recorded onto a cassette tape by utilizing an audio cassette tape recorder under the control by a microprocessor. The microprocessor assigns '0' digital data bit a time sequence of a shorter pulse of a single period (T.sub.1) and having a duty cycle of 50% and a longer pulse of a single period (T.sub.2) and having a duty cycle of 50%. Assigned to '1' data bit is a time sequence of a single period of T.sub.2 pulse and a single period of T.sub.1 pulse. An analog signal applied to the recording unit of the audio cassette tape recorder initiates a gradual increase in its level at a point of transition from the low level L to the high level H of either T.sub.1 or T.sub.2 pulse, and returns to a start level at a point of transition from the H to the L level and also initiates a gradual decrease in the level. In this manner, a waveform conversion is performed. As a result of such waveform conversion, a signal reproduced from the cassette tape has a waveform which can be easily determined to represent either one of the binary data bits. The use of pulses having duty cycles of 50% as reference waves minimizes a level fluctuation in the reproduced signal which may be caused by a time constant of the reproducing unit of the tape recorder.

Analog magnetic recording system for binary signals

A motor control system for one stitch sewing control of a sewing machine is disclosed. Motor speed is controlled by controlling the trigger phase of motor drive thyristors. Two needle position detectors are employed to detect the arrival of the sewing needle at predetermined halt positions. A pair of motor speed indication signal generator circuits, a pair of memory circuits and a start pulse generator circuit are employed. When the one stitch sewing mode is selected and the foot controller is forced down, the first memory circuit memorizes the start of one stitch sewing and energizes the first motor speed indication signal generator circuit so as to drive the motor of the sewing machine at a predetermined sewing speed. When the first needle position detector detects the arrival of the sewing needle at the lowered halt position, it deenergizes the first memory circuit and the first motor speed indication signal generator circuit, and energizes the second memory circuit for energizing the second motor speed indication signal generator circuit so as to drive the motor at a predetermined lower sewing speed. When the second needle position detector detects the arrival of the sewing needle at the raised halt position, it deenergizes the second memory circuit and the second motor speed indication signal generator circuit. Deenergization of the second memory circuit causes a brake command signal which activates a brake means.

Motor control system for one stitch sewing control of a sewing machine

A motor control system for sewing a machine is disclosed in which motor drive thyristors, a trigger phase control circuit for the thyristors to control motor speed, and a dynamic brake control circuit means are employed. The dynamic brake control circuit means includes a shunt thyristor connected in parallel with the armature winding of the motor, and a brake command circuit which triggers the shunt thyristor so as to stop the motor by dynamic braking force. The brake command circuit is energized and triggers the shunt thyristor when a stop command signal and a deceleration detection signal are supplied. Thus dynamic braking of the motor of a sewing machine can be accomplished at a predetermined lower speed. To use the motor as a dynamo for dynamic braking stop control of the motor, a trigger phase clamp circuit is employed. To stop the motor at predetermined halt positions, a timer circuit, a predetermined constant trigger phase command signal generator circuit, and needle position detectors are employed. The timer circuit is energized by the stop command signal and generates a signal in a predetermined time interval, by which the generator circuit is energized and controls the trigger phase of motor drive thyristors to decelerate the motor. The brake command circuit triggers the shunt thyristor when motor speed is within a predetermined threshold level and the needle position detectors detect the lowered halt position or the raised halt position of the sewing needle or thread take-up lever.

Motor control system for sewing machine

A motor control system for a sewing machine is disclosed in which motor drive thyristors, a trigger phase control circuit for the thyristors, a comparator circuit for generating a trigger phase indication signal to accelerate or decelerate the motor to an indicated speed which corresponds to force downward on a foot controller, needle position detector means, a brake command circuit, and a predetermined constant trigger phase command circuit are employed. The predetermined constant trigger phase command circuit, which is energized by a stop signal from the foot controller, supplies a predetermined trigger phase indication signal to the trigger phase control circuit to lower the motor speed. The brake command circuit generates, at the time when the needle position detector means detects the sewing needle at a predetermined halt position, a brake command signal. The brake command signal is supplied to a brake means, e.g., dynamic brake means, mechanical brake means, etc., to stop the sewing needle or thread take-up lever at a predetermined 'halt' or stop position. A timer circuit is preferably connected between the foot controller and the predetermined constant trigger phase command circuit to deenergize the predetermined constant trigger phase command circuit and stop the motor after a predetermined time interval. This timing operation of the timer circuit prevents overheating of the motor when the sewing needle stops accidentally before reaching the predetermined halt position.

Growing community of inventors

Anjyo, Japan

Nobuyoshi Nagura