초록 ▼

A corded/cordless dual-mode power-operated device, such as a household vacuum cleaner, can be operated in corded mode from a conventional power source and in a cordless mode using energy provided from an internal rechargable battery and which includes an internal battery charger for recharging the b

A corded/cordless dual-mode power-operated device, such as a household vacuum cleaner, can be operated in corded mode from a conventional power source and in a cordless mode using energy provided from an internal rechargable battery and which includes an internal battery charger for recharging the battery when the device is in its corded mode. The internal charger includes a voltage converter that converts input source current to a relatively high DC current that is chopped at a comparatively high frequency, e.g., 25 KHz, by switching devices. The high-frequency, high voltage current is presented to a step-down transformer with the stepped-down output rectified to provide a low-voltage DC suitable for recharging the internal battery when the device is in its corded mode. The voltage converter advantageously provides for the high efficiency conversion of the input energy to meet the charging current demands of the internal battery in a physically compact device.

대표청구항 ▼

A corded/cordless dual-mode power-operated device, comprising: an electrically powered device having a motor therein operable in a preselected voltage range; a rechargeable battery for storing electrical energy for operating said motor; battery charger means for charging said battery; voltage conver

A corded/cordless dual-mode power-operated device, comprising: an electrically powered device having a motor therein operable in a preselected voltage range; a rechargeable battery for storing electrical energy for operating said motor; battery charger means for charging said battery; voltage converter means for providing conditioned electrical power to said battery charger to effect charging of said battery; circuit means having a power cord for connection to a source of electrical energy therethrough and in circuit with said motor, said battery, said voltage converter means, and said battery charger for providing a circuit between said battery and motor when said power cord is disconnected from the source of electrical energy and for providing a circuit, when said power cord is connected to the source of electrical energy, between said power cord and said motor and for providing power to said voltage converter to effect charging of said battery; and wherein the source of electrical energy is an alternating voltage at a first frequency and said voltage converter means converts the first-frequency alternating voltage into an alternating voltage at a second frequency and converts the second-frequency alternating voltage to a lower voltage.