Abstract: A conventional rotary valve in which is provided with a locking mechanism for fixing the degree of aperture so as to prevent misoperation and reduce accidents caused thereby, and even a previously installed valve can be converted to a valve having a locking mechanism, simply by replacing the handle alone. In a rotary valve wherein a valve element that is engaged with a stem is turned by turning the stem, which is connected to a handle, so as to open and close the valve, and having a top flange that is provided on a neck of a valve body that supports the stem, a notch is formed at the peripheral edge of the top flange, and a locking member, having a protrusion that can be latched in the notch in the top flange by way of a torsion spring, is pivotably supported at the center of the handle or on a grip portion thereof.

Abstract: A conventional rotary valve in which is provided with a locking mechanism for fixing the degree of aperture so as to prevent misoperation and reduce accidents caused thereby, and even a previously installed valve can be converted to a valve having a locking mechanism, simply by replacing the handle alone. In a rotary valve wherein a valve element that is engaged with a stem is turned by turning the stem, which is connected to a handle, so as to open and close the valve, and having a top flange that is provided on a neck of a valve body that supports the stem, a notch is formed at the peripheral edge of the top flange, and a locking member, having a protrusion that can be latched in the notch in the top flange by way of a torsion spring, is pivotably supported at the center of the handle or on a grip portion thereof.

Abstract: A charge indicator for a battery functioning to accurately indicate the residual capacity corresponding to changes of the discharge rate of the battery uses a timer output voltage of a timer circuit and is changed corresponding to the discharge rate of the battery by a pulse-period-setting part. The timer output voltage and the voltage corresponding to the residual capacity are differentially amplified in the corresponding voltage of the discharge rate-varying part to change the corresponding voltage of the discharge rate. When the sensed voltage exceeds a predetermined value, the reset part resets the voltage to a corresponding voltage of the fully charged battery.

Abstract: There is disclosed an improved uninterruptible power system used as a back-up power supply for a computer or communication equipment. The system comprises a rectifier for rectifying AC power from a power line, such as the utility line, an inverter for converting the DC power from the rectifier to AC power, a sealed lead-acid battery connected with the junction of the rectifier and the inverter via a first switch, a charger for supplying charging power from a power line to the battery via a second switch, and a control signal generator. The generator monitors the voltage of a power line and the closed circuit voltage of the battery. Usually, the two switches are opened. In the event of the failure of a power line, the generator closes the first switch to supply the load with electric power. After a power line has been recovered, the second switch is closed to charge the battery via the charger only for a calculated short time.

Abstract: A charging control apparatus comprising a switching circuit for controlling a charging current from a charging power source to a storage battery. A reference voltage is provided which increases with a ramp corresponding to a value equal to, or more than, the maximum ramp value of the charging characteristic of the battery and a reference voltage is also provided which increases with time with a ramp corresponding to a value equal to, or less than, the minimum ramp value of the charging characteristic. The terminal voltage of the battery is sensed by a voltage sensor. A first comparator compares the reference voltage and a first sensed voltage from the voltage sensor. The ramp of the reference voltage is switched in accordance with the output of the first comparator. A second comparator compares the reference voltage and a second sensed voltage from the voltage sensor. The switching circuit is controlled by the output of the second comparator.