Fuel injection pump, also known as high pressure pump, is the most important part of the fuel system. The function of the fuel injection pump is to increase the fuel pressure and inject a certain amount of fuel into the combustion chamber in an accurate time according to the requirements of the diesel engine operating conditions. The injection pump requirements are: (1) injection pump fuel supply to meet the needs of the diesel engine in a variety of conditions, that is, when the load is increased for a large amount of fuel: load hours reduced fuel supply. At the same time also ensure that the fuel supply to each cylinder should be equal. (2) According to diesel engine requirements, fuel injection pump to ensure that the beginning of the same time for the fuel tank, that is the same fuel supply lead angle of each cylinder, but also to ensure the same oil supply, and fuel emergency start, stop oil quickly Neat, to avoid drip phenomenon. (3) Depending on the type of combustion chamber and the method used to form the mixture, the injection pump must provide sufficient pressure to the fuel injector to ensure good atomization quality. Fuel injection pump according to their overall structure can be divided into single pump and synthetic pump (whole pump). 1, single pump Single pump is mainly composed of a plunger and plunger sleeve, itself without a camshaft, and some do not even wheel drive components. Due to the simple arrangement of the single pump near the cylinder head, the high-pressure fuel pipe is greatly shortened. Currently, the high-pressure medium-speed and medium-speed diesel engine with a bore diameter of 200 mm or more is used. 2, the synthesis pump The synthesis pump is installed in the same pump with the same number of cylinders of the plunger coupling, a group of injection components per cylinder, driven by the cam corresponding to the camshaft of the pump body. Now the overall fuel pump, remove a pump group to illustrate. Its main components are: camshaft, roller body, plunger and plunger sleeve, plunger spring, rotating sleeve and ring gear, the valve and the valve seat and the pressure pipe and so on. The plunger sleeve and plunger are a pair of major precision couplings in the fuel injection pump. After careful processing and mutual research, their diameter clearance is only 0.001-0.003mm, which can only be changed in pairs and can not be exchanged separately. The plunger sleeve has two holes to make the inner cavity of the plunger sleeve communicate with the oil channel and the longitudinal groove of the right oil hole, wherein the screw is inserted so that the plunger sleeve can be fixed in the pump body and can not be rotated. The upper part of the plunger has an annular groove which communicates with the upper end face of the plunger with a longitudinal groove. Helical hypotenuse from the longitudinal groove to adjust the amount of oil supply. The lower part of the plunger has two shoulders and flanges. The plunger shoulder is inserted in the cutout of the rotating sleeve. The rotating sleeve is freely mounted on the plunger sleeve. The open ring gear is again screwed on the rotating sleeve and meshed with the gear rod. The gear rack is mounted in the longitudinal bore of the pump body and is connected to the governor lever. When the gear rod moves axially under the action of the joystick and the governor, the rotating sleeve and the plunger on each oil pump also rotate by a certain angle. Lower flange with plunger spring on plunger flange. Spring upper bearing on the pump body. The function of the spring is to move the plunger down. The cam on the camshaft acts on the plunger through the roller body to move it upwards. International Valve Trading Network to remind you to buy pumps, gear pumps, please contact the Shanghai Samsung Pump Factory. Roller body is the driving body between the cam and the plunger, which itself is subject to lateral thrust so that the plunger is only subjected to axial force. The lower part of the roller body is provided with a roller which is arranged on the needle roller bearing, and the upper end of the roller body is screwed into the adjusting screw and the insurance nut.
