Patent ID: 8763456
Filing Date: 2014-07-01
Classification: G01F

Abstract:
1. A liquid level detection apparatus that detects a liquid level of a liquid stored in a tank, the liquid level detection apparatus including: a fixed member that is fixed to the tank; a rotation member that is axially supported by the fixed member; a float that floats on the liquid in the tank and performs an up-and-down movement according to the liquid level; an arm member that connects the float with the rotation member, the arm member converting the up-and-down movement of the float into a rotational movement of the rotation member; a magnet member that is held by the rotation member and rotates integrally with the rotation member, the magnet member including (i) two side surfaces defined as a first side surface and a second side surface that oppose to each other and (ii) two end surfaces defined as a first end surface and a second end surface that oppose to each other; and a magnetoelectric transducer that is held by the fixed member and detects a magnetic field generated by the magnet member, the magnetoelectric transducer outputting an electrical signal indicating the liquid level, the rotation member comprising: a contact portion that is in pressing contact with the first end surface that links between the first side surface and the second side surface of the magnet member; a pair of elastic deformation portions defined as a first elastic deformation portion and a second elastic deformation portion that protrude from a first position and a second position on the contact portion, respectively, so as to oppose each other while sandwiching the magnet member, a pair of pawl portions being defined as a first pawl portion and a second pawl portions that oppose each other by protruding in opposing directions from the first elastic deformation portion and the second elastic deformation portion, respectively, a pair of plastic deformation portions defined as a first plastic deformation portion and a second plastic deformation portion that protrude from a first protruding origin area and a second protrusion origin area on the first elastic deformation portion and the second elastic deformation portion, respectively, wherein each of the first plastic deformation and the second plastic deformation portion is engaged with the magnet member so as to be plastically deformed in a crushed state along both (i) the second end surface and (ii) each of the first side surface and the second side surface of the magnet member due to a pressing force from an edge defined between (i) the second end surface and (ii) each of the first side surface and the second side surface of the magnet member, respectively.