US 2004/0169969 A1 · Safety device

Abstract

A safety device of the present invention copes with diverse abnormal conditions, and securely interrupts a driving current of an electric appliance by being combined with a normally used current interrupter. For example, a current interrupter that senses immersion or a ground fault is arranged in a power plug 50 at an end of a power cord 26, and a power switch 31 is connected to one power line 32-1, which is drawn from the power cord 26 to the inside of a hair-dryer 25, and a first sensor 34 and a second sensor 39 of a normal-time open-circuit type, which close a circuit when sensing an abnormal condition, are respectively arranged in a grip part 27 and an air blowing part 28 between the other power line 32-2 and the sensing line 33. When the sensor closes a circuit under abnormal conditions, a current flows into the sensing line 33, and the same state as that at the time of immersion or a ground fault emerges on the side of the current interrupter, so that the current of the hair dryer is immediately interrupted.

Claims10

Dependent claims

A safety device, comprising:

aground-fault sensing power interrupting device, which is arranged between a plug of a power cord for supplying power taken from a commercial power receptacle via the plug to an electric appliance and a power switch of the electric appliance, detecting a ground fault from the power cord and the electric appliance with an electric current sensor using a current transformer, and interrupting a power supply of the power cord based on this detection;
a sensing line which is provided between a pair of power lines of the power cord, and one end of which is connected to one pole on a side of the pair of power lines not via the current transformer;
and
a sensor in an ordinary-temperature normal-time open-circuit state, which is provided in series with a resistor between the pole to which said sensing line of the electric appliance is connected on the side of the power lines and a charging part of a pole on an opposite side, wherein
said sensor electrically generates the same effect as a ground fault for said ground-fault sensing power interrupter by closing a circuit when sensing an abnormal condition, and triggers said interrupter, so that a power supply is interrupted.

2 more elements

A safety device, comprising:

an immersion sensing power interrupting device, which is arranged between a plug of a power cord for supplying power taken from a commercial power receptacle via the plug to an electric appliance and a power switch of the electric appliance, sensing that an electric current flows into a sensing line when a side of the electric appliance, to which the sensing line arranged separately from a pair of power lines of the power cord is connected, is immersed, and interrupting a power supply;
and
a sensor in an ordinary-temperature normal-time open-circuit state, which is provided in series with a resistor between the sensing line connected to said immersion sensing power interrupting device and a charging part of an arbitrary pole within the electric appliance, wherein
said sensor electrically generates the same effect as immersion for said immersion sensing power interrupter by closing a circuit when sensing an abnormal condition, and operates said interrupter, so that a power supply is interrupted.

1 more element

Dependencies are inferred from the claim text.

Safety device

Life of this patent

Safety device

Life of this patent

Abstract

Claims10