摘要:
An uninterruptible power supply (UPS) system includes first and second busses, a first switching circuit configured to selectively couple an AC source to the first and second busses and a second switching circuit configured to selectively couple the first and second busses to a load. The system also includes a storage capacitor and a third switching circuit configured to couple the storage capacitor between the first and second busses. The system further includes a control circuit configured to control the first, second and third switching circuits to generate an AC voltage at the load.
摘要:
A high intensity discharge (HID) lamp driving circuit. The HID lamp driving circuit includes a first pair of switching devices connected to a high frequency resonant filter, and a second pair of switching devices connected to a ripple reducing filter. A HID lamp is connected between the first pair of switching devices and second pair of switching devices, with a dc power supply being connected to the first pair of switching devices and the second pair of switching devices. The first pair of switching devices and the second pair of switching devices are connected to a common ground with the dc power supply. The lamp driving circuit operates in a half bridge topology during a start-up operation mode of the lamp, and operates in a full-bridge topology during a steady-state operation mode of the lamp. The HID lamp driving circuit is operated in an active zero current switching scheme.
摘要:
An uninterruptible power supply (UPS) system includes first and second busses, a first switching circuit configured to selectively couple an AC source to the first and second busses and a second switching circuit configured to selectively couple the first and second busses to a load. The system also includes a storage capacitor and a third switching circuit configured to couple the storage capacitor between the first and second busses. The system further includes a control circuit configured to control the first, second and third switching circuits to generate an AC voltage at the load.
摘要:
A production assembly tool for securing fasteners to a workpiece such as an automobile body. The production assembly tool of the present invention includes a housing which encases a motor, a transmission, a clutch mechanism and a control module. The control module controls the running and braking of the motor and prevents both over and under securing of a fastener caused by falsely detected tool clutch conditions. An improved clutch sensor switch is operatively associated with the control module for detecting clutch disengagement. The clutch mechanism is designed to drive the fastener until the clutch sensor switch detects clutch disengagement and signals the control circuit to stop drive and start braking. The production assembly tool further includes a system for ensuring accurate placement of the power tool motor in the power tool housing subsequent to motor servicing or repair. Further, an adjustment collar located in the tool nose allows selective access to a clutch adjustment mechanism of the tool located within the housing for torque level adjustment. In addition, the tool housing is covered by an integral, self-sealing non-marring overmold exterior. The overmold exterior allows a lubrication needle to be inserted through an aperture located beneath the overmold exterior. After the needle is removed, the overmold exterior subsequently self-seals, thereby preventing dirt from entering the interior of the tool housing and the applied lubrication from leaking.