Diaphragm gasoline pump

Diaphragm gasoline pump

Diaphragm gasoline pumps are representative of mechanical gasoline pumps. They are used in carburetor engines. They are generally driven by the eccentric wheel on the camshaft. Its working conditions are:

①During the rotation of the oil suction camshaft, when the eccentric wheel pushes the rocker arm and pulls down the pump film pull rod, the pump film drops, generating suction, and the gasoline is sucked out of the fuel tank and passed through the fuel pipe, the fuel filter, and the fuel entering the gasoline pump. room.

②Pumping oil When the eccentric wheel rotates through a certain angle and no longer pushes the rocker arm, the pump membrane spring stretches and the jacking pump membrane rises, pushing gasoline from the delivery valve to the float chamber of the carburetor.

Diaphragm gasoline pumps are characterized by simple structure, but due to the thermal influence of the engine, special attention should be paid to ensuring the pumping performance at high temperatures and the durability of the rubber diaphragm against heat and oil.

Generally, the maximum fuel supply of a gasoline pump is 2.5 to 3.5 times larger than the maximum fuel consumption of a gasoline engine. When the pump oil volume is greater than the fuel consumption and the needle valve of the carburetor float chamber is closed, the pressure in the oil pump outlet pipeline increases, which is reflected in the oil pump, which shortens the diaphragm stroke or stops working.

Electric gasoline pump

The electric gasoline pump does not rely on the camshaft to drive, but relies on electromagnetic force to repeatedly suck the pump membrane. This kind of electric pump can freely choose the installation position and can prevent air lock.

There are two main installation types of electric gasoline pumps for gasoline injection engines, which are installed in the fuel supply pipeline or in the gasoline tank. The former has a large layout range, does not require a specially designed gasoline tank, and is easy to install and disassemble. However, the oil pump has a long suction section, which is prone to air resistance and high working noise. In addition, it is required that the oil pump must not leak. This type is rarely used in current new vehicles. The latter has simple fuel pipelines, low noise, and low requirements for multiple fuel leakage, which is the current main trend.

When working, the flow of the gasoline pump should not only provide the consumption required for engine operation, but also ensure that there is sufficient return flow to ensure stable pressure and adequate cooling of the fuel system.