Patent ID: 8763656

Claim:
A device for preventing a fueling error, which permits an insertion of a large-diameter nozzle relative to a nozzle insertion passage and blocks an insertion of a small-diameter nozzle relative to the nozzle insertion passage, the device comprising: axis members adapted to be attached to a housing member defining the nozzle insertion passage; and shutter members rotatably supported by the axis members and slidable in a radial direction of the nozzle insertion passage to move between a blocking position in which the shutter members block the insertion of the nozzle relative to the nozzle insertion passage, and a permitting position in which the shutter members permit the insertion of the nozzle relative to the nozzle insertion passage, wherein each of the shutter members includes a bearing bore elongated in the radial direction of the nozzle insertion passage to rotatably and slidably engage with the axis member, a first abutting portion having a predetermined bore diameter or above, and arranged to abut against the large diameter nozzle to slide in the radial direction of the nozzle insertion passage, and a second abutting portion extending sequentially from the first abutting portions in the nozzle insertion direction of the nozzle insertion passage, allowing-the shutter member to rotate up to the permitting position sequentially to an abutment of the nozzle to the first abutting portions, and the shutter members are configured so that when the nozzle in which the bore diameter is the predetermined value or above is inserted into the nozzle insertion passage, the nozzle abuts against the first abutting portions and the second abutting portions sequentially, so that after the shutter members slide along the axis members outwardly for a predetermined amount in the radial direction of the nozzle insertion passage, the shutter members rotate in an opening direction, and move from the blocking position to the permitting position.