Modularized electric unit pump

Abstract

The invention aims to provide a modularized electronic unit pump (EUP), comprising a magnetic valve, a position connection part and a plunger pressure part; the magnetic valve comprises a valve body, an electromagnet, an electromagnet fill block, an armature and a control valve stem; the electromagnet is installed in an electromagnet housing which is connected with the valve body through the electromagnet fill block; the control valve rod is installed in the valve body, the armature is respectively connected with the control valve rod and the electromagnet; the position connection part comprises a closed hole plate and a position pin; the plunger pressure part comprises a pump body, a plunger, a plunger spring, a tappet and an idler wheel; the plunger is installed in the pump body and is connected with the pump body through the plunger sleeve; a plunger spring is installed outside of the plunger; one end of the plunger is connected with the tappet connected with the idler wheel; and the electromagnet and the plunger pressure part are connected with the position pin together through the sealing hole plate. The invention can reduce the production, assembly and maintenance cost, and improve the consistency and convenience of EUP products.

Description

Technical field [0001] The invention relates to a fuel injection device used in an engine fuel injection system. Background technique [0002] Under the dual pressure of energy shortage and environmental pollution, domestic diesel engine manufacturers have accelerated the pace of product upgrades in recent years. In many fuel injection systems, electronically controlled unit pumps have been used more and more widely in China due to their simple structure, relatively insensitive to fuel quality and high reliability. The electronically controlled unit pump is mainly composed of a plunger and coupling part responsible for the fuel pressurizing part and a high-speed solenoid valve responsible for the fuel injection control part. The current domestic production mode of electronically controlled unit pumps is as follows: first cast the pump body of the unit pump, then process the pump body, process the plunger sleeve on it, and install the solenoid valve to control the valve stem or t...

AI Technical Summary

Problems solved by technology

Therefore, the pump body needs to be finished, so that it can form a precise coupling with the control valve stem and plunger, which increases the processing and manufacturing cost of the pump body of the electronically controlled unitary pump.

[0004] 2. Solenoid valve manufacturing cost is high

The solenoid valve is a high-precision control device, and its parts are precision parts, which require finishing and precision assembly. If the parts of the solenoid valve are manufactured by different manufacturers, it will increase the manufacturing cost of the solenoid valve in the production process. cost

[0005] 3. The manufacturing cost of single pump is high

This will also increase the workload of the unit pump manufacturer in the development and final assembly of the unit pump, resulting in an increase in the manufacturing cost of the unit pump

[0006] 4. Poor product consistency

Due to differences in the technical equipment and process levels of different manufacturers, the precision and shape tolerances of the components of the individual pumps produced by different manufacturers are inconsistent. This inconsistency may cause the individual pumps to be distorted in the final overall assembly. Tolerance magnification

In particular, the solenoid valve is a control device that integrates electromagnetic force, mechanical force and hydraulic force. The action response and interaction of each part are coupled together in a complicated way. The enlarged tolerance and the error caused in the assembly will affect the single pump. The consistency between products and the consistency of the injection characteristics of the fuel injection system will reduce the control accuracy of the solenoid valve, increase the testing and calibration work of the fuel injection control system, and even lead to the inability to form a good cooperation between various parts

[0007] 5. It is difficult to maintain the electronically controlled unit pump, and the maintenance cost is high

The moving parts of the solenoid valve, such as the control valve stem and the armature, do high-speed reciprocating motion during work, withstand high-frequency impact, and are easily damaged

The reliability of the components of the electronically controlled unitary pump is also different. The reliability of the solenoid valve is worse than that of the plunger pressurizing part. Continue to use, and then make the plunger that forms a pair with the pump body unable to continue to use, thus greatly increasing the maintenance cost of the unit pump

In addition, since the solenoid valve body and the pump body are not independent, the maintenance and replacement of the solenoid valve components need to be carried out on the pump body, which also increases the maintenance difficulty of the solenoid valve.

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