Current detection device
View Patent ↗The present invention provides a low-cost current detection device having a magnetic sensor easily placed on a choke coil, wherein assembly and manufacturing costs are reduced and a product is miniaturized. A current detection device including a choke coil for smoothing an input current or an output current and a magnetic sensor 1 a built into the choke coil to detect the input current or output current, wherein the choke coil is composed of: a pair of cores 5 provided with an outer magnetic leg 5 a constituting a closed magnetic circuit and a center magnetic leg 5 b for providing a gap; and an air core coil 6 mounted on the center magnetic leg 5 b , and space 6 b is provided to a part of winding of the air core coil 6 with the magnetic sensor 1 a placed in the gap between the space 6 b and the center magnetic leg 5 b.
1. A current detection device including a choke coil ( 1 ) for smoothing an input current or an output current and a magnetic sensor ( 1 a ) built into the choke coil to detect the input current or output current, wherein
the choke coil ( 1 ) is composed of:
a pair of cores ( 5 ) provided with an outer magnetic leg ( 5 a ) constituting a closed magnetic circuit and a center magnetic leg ( 5 b ) for forming a gap;
a coreless coil ( 6 ) having a space ( 6 b ) at the intermediate portion; and a pair of frames ( 7 ) having a first concave portion ( 7 c ) for housing the center magnetic leg ( 5 b ), a second concave portion ( 7 a ) for housing the magnetic sensor ( 1 a ) and a third concave portion ( 7 b ) for housing the coreless coil ( 6 ).
2. The current detection device according to claim 1 , wherein the coreless coil uses a rectangular wire which is an insulated copper line with a square cross section.
3. The current detection device according to claim 1 , wherein a frame made of an insulating resin is provided on a core's inner circumference portion for wrapping the center magnetic leg in order to secure insulation of the coreless coil and core.
4. The current detection device according to claim 1 , wherein the magnetic sensor uses a Hall IC composed of a Hall element.
5. The current detection device according to claim 1 , wherein a base for fixing the coreless coil and the magnetic sensor is provided.
6. The current detection device according to claim 1 , wherein a metal case including an external terminal for housing the choke coil is provided in order to reinforce fixation of an external circuit board.