RU2290523C1 - Electronic speed governor to control fuel delivery by high-pressure fuel pump - Google Patents

Abstract

FIELD: mechanical engineering; diesel engines.

SUBSTANCE: invention relates to design of electric speed governors of diesel engine fuel-injection pumps. Proposed electronic speed governor to control fuel delivery by high-pressure fuel pump contains electronic control unit, actuating mechanism, control rack position pickup made integral with rack, and magnetic circuit rigidly secured on fuel pump body. Rack position pickup arranged is inside actuating mechanism and winding of position pickup are arranged on inner surface of magnetic circuit.

EFFECT: optimization of layout of electronic speed governor component, reduced overall dimensions from side of drive of fuel injection pump, provision of convenience in repair.

Description

The invention relates to the field of engine engineering, in particular to the design of electronic regulators of high pressure fuel pumps (TNVD) of diesel engines.

The regulator is one of the main components of the diesel high pressure fuel pump. It maintains the constancy of the diesel mode, set from the control panel, limits the maximum and minimum engine speed.

The design of the electronic regulator of the Bosh company (Gorbachenkov V.K. et al. Electronic control systems for fuel supply in diesel engines. - M .: TsNII-TEIavtoprom, 1989, p.15-21) is known, which expands the functions of the regulator, namely, it allows to regulate the flow fuel depending on temperature, pressure at the air inlet to the cylinder, coolant temperature, exhaust smoke, etc.

The design of the electronic controller includes such integral elements as the actuator, sensors for moving the rack and speed, load adjuster, electronic unit, cable network and other sensors necessary to take into account the impact and increase the efficiency of diesel engines (atmospheric and charge air pressure sensors, coolant temperature, air, fuel, etc.).

A disadvantage of the known design of the electronic controller is the use of a rather complex, and therefore less reliable and expensive load adjuster. At the heart of his device is a potentiometric pedal position sensor that sets the mode of operation. The setter is placed in a protective casing, in one of the cavities of which there are two duplicated return springs and a friction disk, which provides normalization of the moments of forward and reverse strokes with the necessary hysteresis for reliable determination of the pedal stroke. To implement the boost mode (“kick-down”), a set-up device is provided in the control unit that creates increased resistance to rotation shortly before the end of the driver’s pedal stroke. Such a surge in the moment of resistance is necessary for a clear fixation of the inclusion of forced modes. The device is regulated by means of spring-loaded balls, turning when turning to a surface of a smaller radius. A potentiometer is located in another cavity of the setter. To achieve high reliability and durability, the conductive path of the potentiometer and movable contact are carefully made of high-quality materials.

Closest to the claimed is the design of the electronic controller (patent No. 2066386, F 02 D 1/08, publ. 09/10/96), containing a control unit, an electromagnetic actuator, while the armature of the electromagnet and the core of the position sensor are made in one piece with the fuel rail a high-pressure pump or a draft roller located parallel to the rail, rigidly connected to it and controlling its movement.

A disadvantage of the known construction is the location of the fuel pump rail position sensor on the high pressure pump side opposite to the actuator, which increases the dimensions of the fuel pump and complicates its design, and considering that it is possible to locate pump drive parts covered by a casing on the sensor side, complicates the process of repairing it.

The invention solves the problem of optimizing the layout of electronic controller devices and the necessary reduction in overall dimensions on the part of the high pressure fuel pump drive, and improving the convenience of repair.

This problem is solved in that in an electronic speed controller for controlling the fuel supply by a high-pressure fuel pump, comprising a control unit, an actuator, a rack position sensor integral with the rack, according to the invention, a position sensor is located inside the actuator, and the sensor windings positions are located on the inner surface of the magnetic circuit.

The location of the rail position sensor and the windings in this way reduce the size of the controller and simplify access to the sensor during repair.

The scheme implements the main feedback on the frequency of rotation of the crankshaft of the diesel engine and additional feedback on the position of the rail of the fuel pump and on the current of the winding of the actuator. Feedback on the frequency of rotation of the crankshaft of the diesel engine is used to maintain a given speed. Feedback on the position of the rail of the fuel pump is designed to provide the necessary range of movement of the rail of the fuel pump. When a signal for setting the speed of the crankshaft (the signal is set in the form of a voltage) is supplied, the controller compares the reference signal and the feedback signal from the speed sensor and generates a control signal (error signal). The amplified error signal, the feedback signal on the position of the fuel pump rail, the signal of the rail speed calculated by direct differentiation of the signal on the position of the rail, and also the current feedback signal are summed, after which it is fed to the input of a power switch operating in a pulsed mode, to the output of which is connected to the armature of the actuator associated with the rail of the high pressure fuel pump. The actuator changes the amount of fuel supply, increasing or decreasing the speed of the crankshaft.

The electronic controller contains a control unit (not shown) connected to all controller nodes via a wired network, an actuator 1, in which the rod 2 of the armature 3 is rigidly fixed to the core 4 of the position sensor 5 of the rail 6, made in one piece with the rail 6 of the high fuel pump pressure 7. The regulator also contains a magnetic circuit 8, rigidly fixed to the fuel pump housing, exciting 9 and measuring 10 of the winding of the position sensor of the rail 4 of the injection pump, located on the inner surface of the magnetic circuit 8, and a core 4 position sensors placed inside the magnetic circuit 8.

Spurious interference induced by the anchor winding of an electromagnet on the measuring winding of the high pressure fuel pump rail position sensor is taken into account by special filters of the control unit and neutralized.

The electronic controller is a closed circuit for automatic control of the diesel engine speed.

The principle of operation of the actuator of the electronic controller is based on the magnetic interaction of a conductor with alternating current, placed in a uniform magnetic field. The magnetic circuit coil 8 connected to a constant voltage source creates a constant magnetic field, in the gap of which is the armature winding 3. The armature winding 3 is supplied with a control current from the control unit. Depending on the magnitude and direction of the control current, the armature 3, rigidly fixed to the rod 2, made in one piece with the rail 6 of the fuel pump, will move left and right, increasing or decreasing the fuel supply.

The proposed design in comparison with the prototype has a reduced size and provides improved repair convenience through the use of the internal space of the actuator.

The proposed modification of the electronic regulator is applicable for all types of diesel engines, does not require a change in the design of the fuel pump, and its cost remains at the same level as its counterparts, with its advantages achieved, which contributes to its introduction into production.

Claims (1)

An electronic speed controller for controlling the flow of fuel by a high-pressure fuel pump, comprising an electronic control unit, an actuator, a rack position sensor integral with the rack, a magnetic circuit rigidly fixed to the fuel pump housing, characterized in that the position sensor is located inside the actuator mechanism, and the position sensor windings are located on the inner surface of the magnetic circuit.