RU1775006C - Diesel engine fuel system - Google Patents

Abstract

Usage: engine, in particular diesel fuel equipment. SUMMARY OF THE INVENTION: A fuel supply system in an internal combustion engine consists of a booster and control unit, a high pressure unit. The pumping unit is formed by a housing (K) 1 with a longitudinal cylindrical hole 2, with an outlet channel 4 and an inlet 3 with a valve, of variable cross-section by a plunger (P) 12, a sleeve 5, an elastic diaphragm 18 with rings 19 rigidly connected to it and to each other. forming a rigid center. The diaphragm divides the space in the 2 K 1 hole into a pumping chamber. VI VI sl Os

Description

chamber 20 and chamber 21 for accommodating spring 22 and can be moved along P 12, having a drive from it and spring 22. The control unit 26 acts as a local variable hydraulic resistance to the flow of fluid leaving the pumping unit. The high-pressure assembly is formed by a sleeve 5 having a longitudinal cylindrical hole 6 with a restrictive protrusion 7, which also represents an adjustment element, an inlet channel 8, shut-off channels 8, 9a, and the like. (each for its internal combustion engine cylinder), a drain channel 10 for leaking fuel and air bypass, an opening 11 for introducing a manual fuel pumping element, a plunger 12 and a piston 23 with a spring 24 inside the opening 6 of the sleeve 5. P 12 moves back and forth and rotates at a certain angle (drive P 12 is not shown) in the hole 6 and has an inlet channel 13 connected to an annular groove 17, compatible with the inlet channel 8 of the sleeve

for filling the pressure chamber 25 with fuel, the discharge valve 16 (installed for better sealing, it is not necessary to use it) in the channel 14 connected to the shut-off hole 15, compatible with one of the shut-off channels 9, 9a and the like. for displacing fuel to the nozzle 31.31a and the like. The spring-loaded piston 23 has the possibility of axial movement inside the bore 6 of the sleeve 5, changing the volume of the pressure chamber 25 under its lower face, which is important for controlling the amount of fuel injected into it when changing the operating modes of the internal combustion engine. Fuel enters the system through the fuel line 32 from the fuel tank 34. For primary fuel cleaning, use the filter 33 located after the fuel tank, to better clean the fuel before it enters the high-pressure unit, filter 27 is used. Sealing 28, technological 29, fixing 30 Elements ensure the health of the system. 1 C.p. f-ls, 2 ill.

The invention relates to mechanical engineering, and more specifically to engine manufacturing. Designed for use in diesel internal combustion engines (ICE).

Various systems are known for supplying fuel to diesel ICEs, the main disadvantages of which are the complexity of construction, adjustment, and the need to use additional support units.

To the application number 59-45812, cl. F 02 D 02, F 02 M 59/20, published 11.08.81 in Japan, a solution has been proposed in a device for injecting fuel into a diesel engine that eliminates some of the drawbacks of existing fuel systems. In this application, it is proposed to change the phase of fuel injection by changing its volume. This is a noteworthy technical solution, but the disadvantage of this application is that a complex microprocessor automation system has been proposed to implement the idea.

In the application No. 5137-70, cl. F 02 M 41/04, registered by Czechoslovakia Patent No. 148078 and published on 05/31/72, in a distribution injection pump for multi-cylinder internal combustion engines, a simple method for changing the amount of fuel injected into the cylinders of an engine is carried out by using a positioning piston in the injection pump. The design of this injection pump is simpler than the others and has a number of operational advantages over them. But in this invention does not solve the problem of changing the lead angle

a fuel injector with a change in the internal combustion engine operating modes, since the start of fuel injection by the pump remains constant in all modes, and only the end time of the injection changes. In the proposed pump

large area of precision surfaces with a very high cost of production. At the same time, both considered technical solutions without additional nodes cannot provide work

ICE.

The normal operation of a diesel ICE is currently provided by fuel systems incorporating various support units.

A known system consisting of a fuel tank, a diaphragm booster pump in communication with a fuel tank, a filter, a distribution type high pressure fuel pump in communication with a fuel booster pump and cylinder nozzles, a fuel injection advance clutch and an operating mode regulator operating mode adjustment

ICE operations through appropriate adjustment of the characteristics of the high-pressure fuel pump (see, for example,

Finelab B.N. Fuel equipment of automotive diesel engines. Directory. - Leningrad: Engineering, Leningrad Branch, 1974. - p. 59 ... 61). The system under consideration allows the operator to easily change the operating modes of the internal combustion engine and automatically return to the initial state of work selected earlier by the operator in a certain range when the applied load suddenly changes. In this case, the internal combustion engine operating modes proceed with the optimum angle of advance of fuel injection.

But the specified system for the implementation of its functionality must have additional support units: a clutch for changing the fuel injection advance angle with changing engine operating modes, complex and insufficiently reliable automatic mode controller and an engine control unit for the engine operator, a separate drive to the booster pump.

On the whole, this complicates and increases the cost of design and operation, and makes increased demands on repair equipment and personnel operating and setting up fuel systems.

The aim of the present invention is to provide a simple system for supplying fuel to a diesel engine, which requires the smallest number of units providing its operation and, having an appropriate design, is self-regulating.

This is achieved by the fact that when the DVM operating modes change, the amount of fuel pumped by the pump and its injection moment through the nozzle into the cylinders are controlled by changing the hydraulic resistance of the control unit and the pressure applied to the spring-loaded piston in the cap by the pressure of the fuel passing through the control unit to the high pressure unit. The feed and control units, as well as the high-pressure unit, are structurally integrated and share a common drive.

The unit that regulates the operating modes of the engine also serves to automatically adjust when the load on the internal combustion engine changes. Such adjustment is carried out: - by the angle of advance of the fuel injection based on the coordination of the amount of fuel pumped for a given operating mode and the height of the liquid column in the high-pressure chamber; - by load - based on the coordination of fuel consumption through the control unit and the load on the internal combustion engine. For manual pumping of fuel, the system allows manual pumping.

In FIG. 1 shows a longitudinal section of the fuel system in the position of displacing fuel from the pumping unit through the control unit with significant

filling the high-pressure unit at an engine operating mode close to maximum; in FIG. 2 schematically shows the dependence of the increase in the fuel injection advance angle with the increase in the engine operating mode (increase in the crankshaft speed).

ICE fuel supply system can

to ensure the operation of a diesel engine.

The system has a booster unit,

5 formed by a housing 1 with a longitudinal cylindrical hole 2, of variable cross-section by a plunger 12, a sleeve 5, an elastic diaphragm 18 with rings 19 rigidly connected with it and with each other, forming a rigid center. A fixed-center diaphragm 18 divides the space in the housing .1 into a booster chamber 20 and a chamber 21 for receiving a return spring 22 and is free to

5 movement along the plunger 12, alternately changing the volume of the pumping chamber 20 and providing fuel injection through the inlet 3 with the valve and forcing it out at the outlet 4 (the valve is not covered in this case) through the control unit 26 and the fuel filter 27 to the high pressure unit. The rigid center of the diaphragm 18 is driven by the moving

5 reciprocatingly and rotationally of a plunger 12 of variable section and a return spring 22 mounted in the chamber 21.

For manual swapping

0 of fuel in the pumping unit, an opening 11 is provided for guiding a special element engaging with a coil of spring 22.

The regulatory unit 26 plays the role of

5 variable resistance to liquid fuel flow.

The high-pressure unit is formed by a sleeve 5 having a longitudinal cylindrical hole 6, an inlet channel 8, cut-off channels 9, 9a, for example, a channel 10 for draining leaked fuel and air bypass, a hole 11 for introducing a manual fuel pumping element, plunger 12, a piston 23 with a spring 24, a limiting 5 protrusion 7, which performs the functions and an adjusting element (changing its vertical position when screwing in and out on the thread). A plunger 12 of variable cross section with an inlet channel 13 connected to an annular groove 17 around the plunger, with a discharge valve 16 (used for better sealing, but not obsolete) in the channel 14, the shut-off hole 15 moves reciprocally in the hole b sleeve 5 and rotates a certain angle (the actuator assembly of the plunger is not shown, as it may be traditional) to communicate the shut-off hole 15 with any of the shut-off channels 9, 9a and the like. The cut-off channels 9 in the sleeve are as many as the nozzles 31 in the engine.

Fuel enters the high-pressure unit when the inlet channel 13 of the plunger 12 is combined with the inlet channel 8 of the sleeve 5. In the hole b of the sleeve 5 above the plunger there is a freely moving piston 23 with a spring 24, while moving along the axis it changes the volume of the pressure chamber 25. (C in order to improve the manufacturability of the system and reduce the number of precision surfaces during manufacture, the piston 23 may be cut off from the plunger after creating the precision surfaces). The amount of fuel entering the high pressure unit depends on the position of the valve in the control unit 26.

A condition for the proper operation of the system is that the stiffness of the spring 22 in the pumping unit is higher than the stiffness of the spring 23 in the high-pressure unit.

Fuel is supplied to the system from the fuel tank 34 through a purification filter 33 through a fuel line 32. To improve process performance and maintainability, the system comprises sealing 28, technological 29 and fastening 30 elements.

The system is designed to work primarily with conventional nozzle valves.

The high-pressure unit of the system can be used in internal engines

Combustion having a fuel pump of a high pressure type.

Claims (2)

1. Diesel fuel supply system, containing a fuel tank, diaphragm a booster pump with a working cavity and a diaphragm in communication with the fuel tank, a filter, a distribution type fuel pump communicated through a filter with a diaphragm pump, nozzles connected to a distribution type fuel pump, the distribution type fuel pump being made in the form of a housing with a sleeve, a stepped plunger. installed in the sleeve with the possibility of translational movement, the piston with the adjusting element mounted coaxially with the plunger in the sleeve with the formation between the last discharge cavity, discharge valve, characterized in that, in order to simplify the design, the working cavity of the diaphragm booster pump is made in the housing of the distribution type fuel pump, the diaphragm of the booster pump is spring-loaded with a rigid center freely mounted on the part of the plunger of smaller diameter with the possibility of interaction a rigid center with end surfaces of the larger part of the plunger, the diaphragm at the periphery is rigidly connected to the housing, the adjusting element is made with protrusion and spring-loaded relatively piston, a cut-off cavity is made in the plunger, in communication with the discharge cavity through the discharge valve, a part of the housing with the sleeve is detachable, and the plunger is installed in the sleeve with the possibility of rotational movement. 2. The system according to claim 1, characterized in that it is equipped with an adjustable choke installed between the working cavity of the diaphragm pump and the filter. min them. o) filling Lh 5) injection Maxim.