The function of the fuel pump armature

　　When it comes to the automotive fuel delivery system, the first thing that comes to mind is the fuel pump, because without the fuel pump, fuel cannot be supplied to the engine, and the previous P0087 fault code also mentioned the fuel pump. So Fuel pump armature What exactly does it do? Let me explain.

　　Considering heat dissipation, sound insulation, and air resistance, the current fuel pump armature is built into the fuel tank. Its main function is to draw fuel from the fuel tank, pressurize it and deliver it to the fuel supply pipe, and maintain a certain fuel pressure through the fuel pressure regulator.

　　Generally speaking, the fuel pump armature is actually a fuel pump component, a whole component. It contains multiple components, mainly composed of a filter (fuel filter, oil filter), a fuel pressure regulator, a fuel pump, and a fuel level sensor unit (float).

　　1. Currently, most vehicle fuel pumps are installed in the fuel tank. The electrically driven fuel pump consists of three parts: the pump body, the permanent magnet motor, and the housing.

　　2. Fuel flows through the electric fuel pump, cooling the armature of the permanent magnet motor, also known as a wet fuel pump. The motor part of the electric fuel pump includes a permanent magnet fixed to the housing, an armature that generates electromagnetic torque, and a brush assembly installed on the housing.

　　3. The brushes contact the commutator on the armature, and the leads connect to the terminals on the housing, guiding the voltage that controls the electric fuel pump to the armature windings.

　　4. The additional functions of the fuel pump are performed by the safety valve and the check valve. The safety valve prevents the fuel pipe from rupturing or the fuel pump from being damaged due to excessive pressure when the fuel pipe is blocked. The pressure regulator has the function of regulating and stabilizing pressure, and controls the fuel pressure at around 0.4 MPa (the specific pressure value may vary depending on the engine model). The pressure regulation method is to open the valve when the fuel pressure exceeds the spring pressure of the pressure regulator, allowing the fuel to flow back to the tank, so that the fuel pressure reaches a constant value.

　　The fuel pump armature filter includes an oil filter and a fuel filter, commonly known as a coarse filter and a fine filter, which mainly filter impurities from the fuel. The main function of both is fuel filtration. The structure of the fuel filter consists of an aluminum shell and a stainless steel bracket. A high-efficiency filter paper is installed on the bracket, and the filter paper is in a daisy shape to increase the flow area. Its main function is to remove solid impurities such as iron oxide and dust from the fuel to prevent blockage of the fuel system (especially the injectors). The fuel pump operating time and duration are controlled by the ECU according to the actual vehicle conditions. The fuel pump is directly powered by the battery, and the fuel pump relay controls its on/off. Fuel pump circuit problems are often caused by fuel pump relay failure.