JPS5862330A - Electronic control governer - Google Patents

Abstract

PURPOSE:To improve the countermeasure to exhaust gas and the economical efficiency of fuel in a control governer of an internal combustion engine by providing an electromagnetic solenoid to control the amount of displacement of a plunger for controlling the timing and the amount of fuel injection with high accuracy. CONSTITUTION:Fuel is compressed by the vertical reciprocation of a plunger 1. This vertical reciprocation of the plunger 1 is carried on by a coil 2 and a permanent magnet 3, and the electric supply to the coil 2 is changed for controlling the timing and the amount of fuel injection. The fuel is supplied from a pump 8 of a low discharge pressure into a low-pressure chamber 9, and compressed into a high pressure in a high-pressure chamber 11. This construction permits to control the timing and the amount of fuel with high accuracy, and therefore, is advantageous in the countermeasure to exhaust gas and the economical efficiency of fuel. Since the pump 8 is available in a low discharge pressure, the economical efficiency and the controllability are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a governor that controls fuel injection timing and injection amount in a system such as a diesel engine that supplies fuel directly to a combustion chamber at high pressure, and is particularly suitable for electronic control. It is something that

In conventional governors for engines that directly supply fuel to the combustion chamber, the mechanism for controlling injection timing and injection amount was performed mechanically using a cam or the like.

Even in governors that incorporate electronic control, only the injection timing is electronically controlled, and the injection amount is controlled mechanically. , Such mechanical control has the disadvantage that optimal control is not performed and K cannot be applied to exhaust gas countermeasures.

1+, us, P4219, 1 s 4 includes a method of controlling the stroke of the pressure booster piston using an electromagnetic switching valve, U, aP4
No. 022166 discloses a method of controlling the opening and closing of an injection valve using an electrostrictive element, but the mechanism is complicated.

An object of the present invention is to provide a governor for an in-cylinder direct injection system that can electrically control fuel injection timing and injection amount.

The governor of the present invention uses the attraction and repulsion forces of opposing magnets to raise and lower the plunger, which compresses fuel to high pressure, and one of the magnets is an electromagnetic solenoid. The amount of displacement of the plunger is controlled by the magnitude of the supplied current.

FIG. 1 shows the overall configuration of an electronically controlled governor according to the present invention. Here, the fuel is compressed by moving the plunger 1 up and down. This vertical movement of the plunger 1 is performed by the attractive force and repulsive force of the coil 2 and the permanent magnet 3. The plunger is also rotated by a shaft 4 that rotates at 1/2 the rotation speed of the crankshaft, and is connected to a distribution passage 5 in the plunger 1 and a nozzle 6.
The fuel passages 7 are communicated with each other at appropriate times. Here, fuel is pumped into a low pressure chamber 9 by a pump 8 with a low discharge pressure.
As the plunger 1 descends, the fuel passes through the Chetsuta valve 10 and is sent to the high pressure chamber 11, where the compressed fuel passes through the fuel passage 7 and delivery valve 12 and is supplied to the automatic valve 13. Since the fuel is compressed to a high pressure in this high pressure chamber 11, the pump 8 may have a low discharge pressure. Here, the check valve lO is configured such that when the plunger 1 is lowered by an arbitrary distance,
This is to supply an amount of fuel proportional to the amount of movement to the high pressure chamber 11, and when the fuel is compressed in the high pressure chamber, to prevent backflow of fuel to the low pressure chamber 9 side. Valve 1
Second, the purpose is to improve fuel exhaustion and to prevent fuel from flowing back from the automatic valve 13 side to the high pressure chamber 11 side after injection. Although there is only one distribution passage 5, the number of fuel passages 7 is equal to the number of cylinders in the housing 6.Next, the rotation and vertical movement mechanism of the plunger 1 will be explained. The rotational movement is achieved by the shaft 4 being connected to the crankshaft via a transmission mechanism, and the rotational movement is at a crank rotation speed of 17.
It is rotating at a speed of 2. FIG. 2 shows the part of the magnet that causes the vertical movement. FIG. 2(a) shows the permanent magnets attached to the plunger 1 side viewed from above, and eight permanent magnets 3 are arranged in a circumferential shape with alternating polarities.

FIG. 2(b) is a view of the coil 2 on the housing 6 side seen from the bottom of FIG. be. The arrow in FIG. 2(a) indicates the opening direction of the distribution passage 5 provided with the plunger IK, and the arrow in FIG. 2(b) indicates the opening direction of the distribution passage 5 provided with the plunger IK.
This is the opening direction of the fuel passage 7 provided in the housing 6. FIG. 3 shows the vertical movement of plunger l. FIG. 3(a) is a diagram when the S pole of the permanent magnet 3 on the plan key 1 side matches the N pole on the housing 6 side. In this case, the distribution passage 5 and the fuel passage 7 match. It is also a time when At this time, when a current is passed through the coil 2, the plunger 1 rises due to the attraction force, compressing and injecting the fuel. FIG. 3(b) shows a state where the ON pole on the plunger 1 side and the coil on the maggot puffer fish 6 side coincide with each other, and when a current is passed through the coil 2 at this time, the plunger 1 is lowered by the repulsive force.

FIG. 4 is an enlarged view of the vicinity of the distribution passage 5 within the plunger l. An enlarged groove 14 is provided at the tip of the distribution passage 5 so that the passage can be connected even if the plunger 1 moves up and down by the lift width A.

Moreover, this enlarged groove 14 has a rotational angle at which injection is possible, that is, an angle within the angle between the S pole of the plunger 1 and the coil 2.
They are also provided in the circumferential direction with a width of 5°.

FIG. 5 shows a fuel injection chart.

The plunger 1 rotates once while the crankshaft rotates twice. Plunger control position is plunger 1
When the S pole and the coil match, it can be raised and N
The injection timing control width is within 90' of crank angle, indicating that the pole and coil can be lowered when they become high. When current is applied to the coil during the period when the plunger control position is lowered, the plunger is raised by the repulsive force of the magnet, and the plunger lift is lowered as shown in the figure. Also, if a current is passed through the coil during the lift, the Pushinger lift will return to its original position due to the attractive force of the magnet. In order to control the tamp injection timing, it is sufficient to control the timing at which current is passed through this coil.

Furthermore, in order to control the amount of fuel, if the amount of descent of the plunger 1 after injection is controlled by changing the current flowing through the coil, the amount of fuel entering the high pressure chamber 11 through the check valve 1o will be q. ” k l (1) where q: amount of fuel injected at one time / descending distance of the nib plunger: constant Since it is as shown in equation (1), the amount of fuel is controlled. The relationship between the amount of jar movement l and the current ■ is determined by the following equation.

2-□ N 2 j t a 3 3 ,, (2) Here F:
Force applied to the plunger N: Number of turns of the coil ■: Current S: Cross-sectional area μ: Permeability , is always assumed to be constant. Therefore, equation (2) is l! oe I
(3), the amount of plunger movement and the current are proportional, and it becomes possible to control the amount of fuel using the current.

Immediately after the plunger has finished measuring a large amount of fuel by descending, the fuel pressures in the high pressure chamber 11 and the low pressure chamber 9 are equal. However, due to the difference in pressure receiving area, the plunger As the force is applied, the fuel pressure in the high pressure chamber 11 becomes somewhat high, the check valve 1° closes, and the plunger remains in place until the attraction force is generated by the next current pulse. I will do it.

FIG. 6 shows the relationship between the stroke of the plunger 1 shown in FIG. 1 and the force generated therein, that is, the suction force. The curve changes depending on the current supplied to the coil. But big suction power with small strokes? It can be seen that there are parts where injection pressure can be obtained.

Furthermore, FIG. 7 shows the relationship between the current supplied when the plunger descends, that is, when measuring fuel, and the amount of injected fuel, which is a straight line and is suitable for electronic control of fuel metering.

In Fig. 5, when the plunger control position is in the raised position, a coil current is applied to create an electromagnetic force, and when the plunger 1 rotates, the electromagnetic force is automatically increased and the plunger 1 is moved upward. Push up. At this time, the start of movement of the plunger 1 is determined by the coil current. When reciprocating the plunger 1 using a conventional electromagnetic solenoid, the response is affected by the inductance of the electromagnetic solenoid, but in the present invention, it is not affected by the inductance.

FIG. 8 shows another application example of FIG. 1, in which a coil 16 is also provided in the housing 15 on the shaft 4 side! The interaction with recoil 2 increases the suction force and improves responsiveness.

FIG. 9 is an example of an application of the arrangement of magnets and coils shown in FIG. 2. Here, the S-pole permanent magnet at the position where the attractive force is generated is increased in size, which has the effect of increasing the attractive force and widening the control range of the injection timing. Note that the N pole may be made smaller since it is sufficient to measure at the same place every time.

Conventionally, when reciprocating motion is performed using electromagnetic force, the response is affected by the inductance of the electromagnetic coil, and
It was difficult to obtain a response of less than s. In contrast, in the present invention, since the magnet is forcibly moved by rotation, the reciprocating motion follows the rotation without delay and is not affected by the inductance of the electromagnetic coil. Therefore, a response time of 1 ms or less can be ensured, and fuel can be accurately measured even in an operating range where the engine speed is high.

According to the present invention, in a high-pressure fuel cylinder injection system such as a diesel engine, injection timing 1. Since the injection amount can be electrically controlled freely and accurately, it has the effect of being more advantageous than conventional mechanical systems in terms of exhaust gas countermeasures and fuel economy.

Since the fuel is compressed in a high-pressure chamber, a low-pressure pump is sufficient, making this a major advance in terms of economy and controllability compared to conventional high-pressure pumps.

The movement of the plunger 1 can also be detected electrically and fed back.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention, and FIG. 2 (aX
b) is a magnet arrangement diagram, Figure 3 (aXb) is a diagram of the principle of operation of the plunger, Figure 4 is an enlarged view of the distribution passage in the plunger, Figure 5 is a chart diagram of injection control, and Figure 6 is a diagram showing the relationship between plunger stroke and attraction force, Figure 7 is a diagram showing the relationship between coil current and injection amount, Figure 8 is a configuration diagram of an application example of Figure 1, and Figures 9 (a) and (b) are diagrams showing the relationship between coil current and injection amount. FIG. 2 is a diagram showing an application example of FIG. 2; DESCRIPTION OF SYMBOLS 1...Plunger, 2...Coil, 3...Permanent magnet, 4...Shaft, 5...Distribution passage, 6...
Housing, 7... Fuel passage, 8... Pump, 9...
...Low pressure chamber, 10...Check valve, 11...High pressure chamber, 12...Delivery valve, 13...Automatic valve Lesson Pi'i Distortion No. 6 Hard Straw Loaf ￥7 Eye Coil Electric Age No. 84 JP)tI Ward

Claims (1)

[Claims] 1. In the governor of an internal combustion engine, which injects high-pressure fuel directly into the combustion chamber, the fuel is kept at high pressure, and the timing and amount of fuel injection are controlled by setting magnets and coils facing each other and changing the coil current. An electronically controlled governor featuring