JPH039308B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrohydraulic combustion control system such as a fuel injection timing detection device or an intake/exhaust valve opening/closing timing detection device in an internal combustion engine. As is well known, the function of the fuel injection system for internal combustion engines, especially diesel engines, is to inject fuel at high pressure and in a spray state into the high-pressure, high-temperature air inside the combustion chamber. The torque is
Since it is determined by the amount of fuel to be combusted, it is necessary to have a function to accurately control the amount of fuel injected into the combustion chamber. Furthermore, the temporal conditions of injection, such as injection timing, injection period, injection rate, and spray condition, are as follows:
Combined with the shape of the combustion chamber, it determines the formation of air-fuel mixture and the combustion pattern, which greatly affects engine performance, exhaust conditions, and exhaust smoke concentration. For this reason, fuel systems that utilize electronic technology have been developed to perform fine injection amount control that adapts to various external conditions. In terms of fuel injection timing detection devices, there is a device that uses the strength of a magnetic field that changes depending on the lift length of a nozzle valve to detect lift (Japanese Patent Laid-Open No. 57-52672
Publication No. 57-93679, Utility Model Publication No. 1987-9367-
Publication No. 109660, Publication No. 127362-127362 and Publication No. 127362
-132068 Publication), which is used for lift detection by providing a mechanical contact point depending on the lift length of the nozzle valve (Utility Model Application Publication No. 109657-1983, Publication No. 76283-1983) , the amount of light shielding that changes according to the lift length of the nozzle valve is used for lift detection (Japanese Utility Model Publication No. 56-109661), which changes according to the nozzle lift length using a sliding brush that works in conjunction with the nozzle valve. One that uses resistance value for lift detection (Japanese Utility Model Publication No. 56-109658), and one that uses capacitance change according to the lift length of the nozzle valve for lift detection (Utility Model Application Publication No. 56-109662) , the amount of strain that changes depending on the lift length of the nozzle valve is detected using a strain gauge (Japanese Patent Application Laid-open No. 118553/1983,
56-109659) and one in which a piezoelectric element detects a load that changes depending on the lift length of a nozzle valve (Japanese Patent Application Laid-open No. 113044/1982) has been proposed. However, in all of these fuel injection timing detection devices, the pressure intensifier, solenoid valve, etc. are installed close to the nozzle spring chamber, which complicates the structure of the nozzle spring chamber and makes it difficult to make it smaller and more compact. It is difficult and costly, the wiring is complicated, disassembly and the structure is complicated, and the serviceability of maintenance is poor.
It is difficult to maintain oil tightness, the temperature changes and increases due to the proximity to the combustion chamber, and the performance changes due to temperature changes of the detection device are large.Furthermore, in the case of a device that uses a light receiving element, the sensitivity of the light receiving element may be affected due to contamination. It includes problems such as change and poor service quality. In particular, when detecting the lift of a solenoid valve and using it as a fuel injection timing detection device, the coil resistance changes depending on the temperature of the solenoid coil portion, and the detection performance changes. That is, if the temperature becomes high, the detection will be delayed, which is a fatal drawback. The present invention was created in view of these conventional problems, and in particular, controls the fuel injection timing detection device or the intake/exhaust valve opening/closing timing detection device by combining electronic technology and hydraulic control technology. Then,
This is an attempt to solve these problems. The structure of the present invention will be explained in detail with reference to embodiments shown in the accompanying drawings. FIG. 1 is a system diagram of the combustion control system of the first embodiment, where 1 is a fuel tank, 2 is a fuel filter, and 3 is a system diagram of a combustion control system according to a first embodiment.
is a fuel oil supply pump, 4 is a fuel oil pressure regulating valve, 5 is a timing sensor in fuel injection valve A, 6 is a servo piston of same A, 7 is a plunger of same A,
8 is a nozzle, 8' is a nozzle spring, 9 is a flywheel, 10 is a rotational phase angle sensor, 11 is a solenoid coil of fuel injection valve A, 12 is a hydraulic valve of fuel injection valve A, that is, a spool valve, and 13 is the spool valve 12.
14 is an inlet, 14 is an outlet, 16 is a servo piston chamber, 17 is an outlet, 18 is a plunger chamber, 1
9 is a nozzle oil reservoir chamber, 20 is an active core, 21 is a supply valve, 22 is a solenoid spring in the timing sensor 5 provided at the top of fuel injection valve A, 23 is a solenoid spring provided at the bottom of fuel injection valve A, and 24 is an asian valve. shows the strike bolt, and also
In the intake/exhaust valve B, 36 is a piston, 37 is a timing sensor, 38 is a solenoid coil, 39 is a hydraulic valve, that is, a spool valve, 40 is an inlet of the spool valve 39, 41 is an outlet of the spool valve 39, 42 is a piston chamber, 43 is a piston chamber 4
2, an inlet and an inlet, 44 a plunger chamber, 45 an active core, 46 a solenoid spring in the timing sensor 37, 47 a solenoid spring provided at the bottom of the intake/exhaust valve B, 48 an adjustment bolt, and 49 an intake/exhaust valve B. An exhaust valve, 50 is an intake/exhaust spring, 51 is an intake/exhaust port, 52 is a valve seat, and 53 is a cylinder head. C is an electronic control system, 54 is a microcomputer, the one shown is for a 4-stroke, 6-cylinder diesel engine, 55 is a group of signal lines to the intake valve, and 56 is a group of signal lines to the exhaust valve. A group of signal lines, 57 is a group of signal lines to fuel injection valve A, 58 is a group of signal lines to exhaust valve timing sensor ₃₇₁ , 59 is a group of signal lines to intake valve timing sensor 3
7 Group of signal wires to ₂ , 60 is fuel injector A
The group of signal lines to the timing sensor 5 is shown in FIG. F is a commonly known piezoelectric ceramic (or a strain gate may be used) as shown in the prior art, and is not particularly shown, but as is well known, when force is applied, voltage increases. , on the other hand, utilizes the property that force is generated when a voltage is applied, and is an aggregate of microcrystals having an ABO ₃ perovskite structure. When the restricting portion 63 is compressed by applying an impact force, a positive voltage is generated. Based on this detection signal, combustion injection valve A or intake/exhaust valve B is
It can be used as a substitute for detecting the timing of valve opening or closing. That is, solenoid coil 1 of fuel injection valve A
1 is operated for a long time, solenoid coil 11
The temperature of the solenoid rises, the resistance value of the coil increases, the acting force of the solenoid weakens, and the time from energization until it collides with the lift limiter 63 becomes longer (that is, the valve opening timing is delayed), but the active core 2 of the solenoid
The present inventor has discovered that the time from when spool valve 12 starts moving until it collides with lift limiter 63 hardly changes;
Since the change in hydraulic pressure propagation time from 0 to nozzle 8 is small and can be ignored (this point has also been elucidated by the inventors, Japan Society of Mechanical Engineers paper, August 1973), in other words, the rotational phase angle sensor 10 and the active core 20
The timing of energization of the solenoid coil 11 can be controlled based on the timing of collision, and the timing of fuel injection can be controlled. In addition, D is a fuel oil supply system, E is an engine main body, 61 is an accumulator, and 62 is an oil pipe. The illustration in FIG. 1 shows the compression and expansion strokes of the engine, while the illustration in FIG. 2 shows the intake and exhaust strokes of the engine in the same figure.
B shows when the solenoid 38 in the intake/exhaust valve B is energized, ie, the intake/exhaust stroke. Now, in the first embodiment configured as described above, the following operations are performed. The microcomputer 54 calculates the signal from the rotational phase angle sensor 10 installed close to the flywheel 9 of the engine body E, and determines the energization timing of the solenoid coil 11 in the fuel injection valve A and the solenoid coil 38 in the intake/exhaust valve B. The current cutoff timing is controlled. Regarding the compression and expansion strokes of the engine, as shown in Figure 1, during fuel injection A, the piston of the engine body E energizes the solenoid coil 11 near the top dead center, so the active core 20 is attracted upward in the figure. The spool valve 12 is pushed up by the action of the solenoid spring 23, and the fuel oil flows into the servo piston chamber 16 via the inlet 13, and the fuel oil in the plunger chamber 18 flows between the servo piston 6 and the plunger 7. The pressure is increased to the cross-sectional area ratio, and the oil is sent to the nozzle oil reservoir chamber 19 and is injected from the nozzle 8. Note that the operating strokes of the active core 20 and the spool valve 12 are adjusted in advance using the adjusting bolt 24. Also, in the same process, in the intake/exhaust valve B, at the beginning of the compression stroke, the intake valve solenoid coil 38 ₁
The current to is cut off. At this point, the current to the exhaust valve solenoid coil 38 ₂ is also cut off. Therefore, when the power to the solenoid coil 38 is cut off, the active core 45 is pushed down by the action of the solenoid spring 46, the oil passage between the fuel oil inlet 40 and the piston chamber 42 is closed, and the piston chamber is closed. 42 flows out from the outlet 41 to the fuel oil tank 1. The pressure in the piston chamber 42 decreases, and the intake/exhaust valve 49 is pushed up by the spring 50 to close the valve seat 52 of the cylinder head 53. Next, regarding the intake and exhaust strokes of the engine,
As shown in the figure, in the combustion injection valve A, when the power to the solenoid coil 11 is cut off, the active core 20 and the spool valve 12 move downward because the downward force of the solenoid spring 22 is greater than the upward force of the solenoid spring 23. is pushed down. Therefore, the oil passage between the servo piston chamber 16 and the fuel oil inlet 13 is closed, and the oil passage to the outlet 14 leading to the fuel tank 1 is opened, and the pressure in the servo piston chamber 16 and the linked plunger chamber 18 is reduced. Go down. Then, the fuel oil supplied to the fuel injection valve A pushes the supply valve 21 downward and flows into the plunger chamber 18. Note that the amount of fuel filled in the plunger chamber 18 is determined by the length of time during which the solenoid coil 11 is de-energized. Also, in the same process, in the intake/exhaust valve B, the solenoid coil 38 of the exhaust valve near the end of the expansion stroke
When power is applied to the intake valve solenoid coil 38 ₁ near the end of the exhaust stroke, the active core 45 is attracted upward, and the spool valve ₃₉
is pushed upward from the solenoid spring 47, fuel oil flows into the piston chamber 42 via the inlet 40 and the outlet 43, and the spring 50
To overcome the load, the intake/exhaust valve 41 is pushed down and the valve seat 52 is opened. Here, to describe the method of controlling the injection amount and rotational speed, the injection amount is changed by changing the length of the energization cutoff time of the solenoid coil 11 of the fuel injection valve A, thereby changing the filling stroke length of the plunger 7. changes. Further, the rotation speed is determined by changing the time interval of the energization cycle (or the time interval of the cutoff cycle) to the solenoid coil 11 of the fuel injection valve A. That is, if the time interval is small, the rotation speed increases. Fuel injection timing control is performed using a rotational phase angle sensor 10 that indicates the position of the piston as a reference cylinder, for example, No. 1 in the figure or reference cylinder No. 1.
This is done by inputting signals from the injection timing sensor 5 of the fuel injection valves A of a plurality of cylinders including 1 and signals such as solenoid temperature to the microcomputer 54, and controlling the energization timing to the solenoid coil 11. Next, FIG. 3 shows a second embodiment of the present invention, in which the same parts as in the first embodiment are denoted by the same reference numerals and their explanations are omitted. A hydraulic oil supply system was included in System D. However, in the second embodiment, the system F is separated. That is, in FIG. 3, 27 is a hydraulic oil tank, 28 is a hydraulic oil filter, 29 is a supply pump, and 30 is a pressure regulating valve, which are connected together with the fuel oil supply pump 3 by a transmission device 64 from the engine body E. , drives the supply pump 29 for hydraulic oil. Furthermore, what is shown in FIG. 4 is a third embodiment of the present invention, in which a fuel oil control system H is further added to the second embodiment. That is, when the solenoid coil 31 of the fuel oil control system H is energized, the solenoid valve 34 is attracted upward against the solenoid spring 32, and the fuel oil supplied from the fuel oil control system H flows through the inlet 33 and the outlet 35. The supply valve 21 of the fuel injection valve A is pushed open downward to flow into the plunger chamber 18 via the fuel injection valve A. Therefore, plunger chamber 1
The fuel filling amount of No. 8 is determined by the energization time of the fuel control system H. In summary, the present invention provides an on-off valve that is mounted on the cylinder head of an internal combustion engine and is opened and closed by hydraulic pressure and a spring, and includes a hydraulic valve that controls the supply of the hydraulic pressure, and an active core that is mounted in the hydraulic valve and the solenoid. This is a control device for a combustion on-off valve of an internal combustion engine by connecting these hydraulic valves or the lift limiting part of the active core and detecting the impact force when they collide with each other, so that it has the following effects. ○…

Claims (1)

[Claims] 1. An on-off valve that is installed in the cylinder head of an internal combustion engine and opens and closes using hydraulic pressure and a spring.
A hydraulic valve for controlling the supply of the hydraulic pressure is provided, the hydraulic valve is connected to an active core installed in a solenoid, and an impact force at the time of collision is detected at a lift limiting portion of the hydraulic valve or the active core. A control device for the combustion on-off valve of an internal combustion engine that controls the on-off valve.