JPH0138168B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention includes an injector device that increases the pressure of fuel oil and injects it using a hydraulic servo mechanism, and a hydraulic valve drive device that controls the opening and closing of an intake valve and an exhaust valve. The present invention relates to an electro-hydraulic control device for an internal combustion engine in which hydraulic control of an intake and exhaust valve device is performed by an electronic control device.

Conventionally, in this type of electronic hydraulic control device for an internal combustion engine, the hydraulic oil for the injector device and the injection oil are supplied from the same hydraulic source (that is, the same fuel oil is used for the hydraulic oil and the injection oil). However, when fuel oil supplied from the same hydraulic source is used as both hydraulic oil and injection oil, for example, if low-quality oil is used as fuel oil, The servo mechanism and solenoid mechanism may become damaged due to rust or abnormal wear on the sliding parts due to increased viscous resistance due to excessive viscosity of the fuel oil, or due to water, sulfur, foreign matter, etc. contained in the fuel oil. An operational failure occurs in the hydraulic actuator, and as a result, responsiveness to changes in the operating state of the engine deteriorates.

In addition, there are some models in which the hydraulic oil for the injector device and the hydraulic oil for the suction and exhaust valve devices are supplied from separate hydraulic sources, but in this case, the structure is complicated and the cost increases. There was a problem that it led to

On the other hand, in terms of controlling the fuel injection amount in the injector device, in the conventional electro-hydraulic control device, the injection amount is adjusted by the energization time length or the energization cutoff time length of the solenoid valve built into the injector device. However, in this case, the temperature of the solenoid coil increases due to the relatively long energization time, which deteriorates its operating characteristics. If the voltage applied to the solenoid coil is suppressed as a countermeasure, a new problem arises in that the excitation attraction force of the solenoid coil decreases and the operating characteristics deteriorate.

In view of the problems of the conventional electro-hydraulic control device for internal combustion engines as described above, the present invention provides a hydraulic oil hydraulic source and an injection oil hydraulic source that are separate systems, and uses the same hydraulic oil for the injector device and the intake and exhaust valve devices. The main purpose is to improve the responsiveness of the hydraulic actuating part, reduce costs, and simplify the structure by configuring it so that it can be supplied from the hydraulic power source. This was done for the other purpose of preventing the deterioration of operating characteristics caused by the temperature rise by minimizing the temperature of the fuel supply driven by the internal combustion engine. A fuel oil supply device having a pump, a hydraulic oil supply device having a hydraulic oil supply pump driven by an internal combustion engine, and a hydraulic servo mechanism to increase the pressure of fuel oil fed from the fuel oil supply device from a nozzle valve. An injector device having an injector section for injecting the fuel and a solenoid valve section for controlling the flow of hydraulic oil that operates the hydraulic servo mechanism, and for controlling the amount of fuel oil supplied from the fuel oil supply device to the injector device side. a hydraulic valve drive device each having a fuel control device, a valve operating mechanism that opens and closes the valve by hydraulic pressure, and a solenoid valve that controls the flow of hydraulic oil that operates the valve operating mechanism. A hydraulically driven intake valve device, a hydraulically driven exhaust valve device, a solenoid coil of a solenoid valve portion of the injector device, a solenoid coil of a solenoid valve portion of the intake valve device and an exhaust valve device, depending on the operating state of the internal combustion engine. It is characterized by comprising an electronic control device having a microcomputer for appropriate control.

Hereinafter, the electro-hydraulic control device for an internal combustion engine of the present invention will be explained with reference to the system diagram shown in FIG.
This electro-hydraulic control device for an internal combustion engine is an internal combustion engine 6.
a fuel oil supply system S having a fuel supply pump 69 driven by the internal combustion engine 8; and a hydraulic oil supply system P having a hydraulic oil supply pump 76 driven simultaneously with the fuel supply pump 69 by the internal combustion engine 68; An injector device T that injects fuel oil, a fuel control device Q that controls the supply amount of fuel oil (injection oil) supplied from the fuel oil supply device S to the injector device T side, and a hydraulic valve drive device that has a hydraulic valve drive device. A driven intake valve device X, a hydraulically driven exhaust valve device Y (details not shown), and an electronic control device R that controls the injector device T, the intake valve device It has

The fuel oil supply device S is configured to pressurize the fuel oil in the fuel tank 71 to an appropriate pressure using the fuel supply pump 69 and supply it to the injector device T via the fuel supply pipe 73.

The hydraulic oil supply device P pressurizes the hydraulic oil in the hydraulic oil tank 77 to an appropriate pressure by the hydraulic oil supply pump 76 and supplies it to the injector device T, the intake valve device X, and the exhaust valve via the hydraulic oil supply pipe 74. It is designed to supply equipment Y.

In the figure, reference numeral 70 is a filter, 75 is a pressure regulating valve, and 72 is an accumulator or collecting pipe for regulating the pressure of fuel oil or hydraulic oil fed from the fuel supply pump 69 or hydraulic oil supply pump 76.

The injector device T includes, in the injector turbo day 1, an injector section 32 that increases the pressure of fuel oil and injects it by a hydraulic servo mechanism 33, and a solenoid valve section 31 that controls the flow of hydraulic oil of the hydraulic servo mechanism 33. are doing. This hydraulic servo mechanism 33 is composed of a large-diameter servo piston 4 and a small-diameter plunger 3, and is connected to a hydraulic oil inlet 22 formed on the side of the injection turbo day 1 through a solenoid valve section 31, which will be described in detail later. By appropriately controlling the introduction and discharge of the hydraulic oil introduced into the servo piston chamber 5 by the solenoid valve section 31, the fuel oil supplied into the fuel oil inlet 40 is transferred to the fuel oil filling oil passage 23. The high-pressure fuel oil is introduced into the plunger chamber 6 through the provided supply valve 21 to increase the pressure, and this high-pressure fuel oil is introduced into the oil reservoir chamber 20 through the high-pressure fuel oil passage 24, and the oil pressure of the fuel oil increases the pressure. Open the nozzle valve 2 and the nozzles 19, 19
It is now being sprayed from... Further, hydraulic oil is introduced into the nozzle valve seat insertion hole 17 provided on the back pressure side of the nozzle valve 2 via a fourth hydraulic oil passage 34, and the opening pressure of the nozzle valve 2 is It is set by the hydraulic pressure in the nozzle valve seat insertion hole 17 and the spring force of the nozzle valve biasing spring 16. Note that the leaked oil from the servo piston 4 is transferred to the fuel tank 7 via the fourth discharge oil passage 30.
Reflux is made to the first side.

The solenoid valve section 31 is a hydraulic servo mechanism 3
3. A spool valve 7 that controls the flow of hydraulic oil introduced into the servo piston chamber 5 to operate the servo piston chamber 5.
and an active core 9 which is driven by the attraction force of the solenoid coil 12 are arranged coaxially. By being displaced in the axial direction, the spool valve 7 opens its two land portions 7.
A first hydraulic oil passage 25 that communicates the hydraulic oil inlet 22 and the spool chamber 8 at a and 7b, and the spool chamber 8.
A second hydraulic fluid that connects the servo piston chamber 5 and the servo piston chamber 5
The oil passage 26 and the third hydraulic oil passage 29, which communicates the spool chamber 8 and the hydraulic oil tank 77, are opened and closed appropriately to control the flow of the hydraulic oil. That is,
When the spool valve 7 is pulled upward,
The first hydraulic oil passage 25 and the second hydraulic oil passage 26 communicate with each other, and hydraulic oil is introduced into the servo piston chamber 5 from the hydraulic oil inlet 22 (FIG. 1, the illustrated position; hereinafter, this valve position will be referred to as (referred to as the first valve position), and conversely, when pushed downward, the hydraulic oil second oil passage 26
This spool valve 7 communicates with the third hydraulic oil passage 29, and the hydraulic oil in the servo piston chamber 5 is discharged to the hydraulic oil tank 77 side (the valve position in this case is referred to as the second valve position). The valve position is controlled by the balance between the attractive force of the solenoid coil 12 and the spring forces of the first spring 14 provided on the active core 9 side and the second spring 15 provided on the spool valve 7 side. That is, in this embodiment, the spring force of the first spring 14 on the active core 9 side is set larger than the second spring 15 on the spool valve 7 side, and when the attraction force of the solenoid coil 12 disappears (in other words, Then solenoid coil 12
), the spool valve 7 and the active core 9 are integrally connected to the first spring 1.
4 and the spring force of the second spring 15 to set the spool valve 7 to the second valve position, and a suction force is generated in the solenoid coil 12 (in other words, the solenoid coil 12
is energized), the active core 9 is first pulled upward against the spring force of the first spring 14 by the suction force, and then the spool valve 7 is pulled up by the spring force of the second spring 15. Therefore, it is pushed upward and set to the first valve position. The stroke of this active core 9, that is, the active core 9
The operating stroke of the active core 9 is adjusted by setting the upward movement limit of the active core 9 using an adjusting bolt 13 provided on the upper surface 9a side of the active core 9.
In addition, the leaked oil from the spool valve 7 is transferred to the first discharge oil path 2.
7 to the hydraulic oil tank 77 via the oil passage hole 11 provided in the active core 9 and the second discharge oil path 28.

The fuel control device Q includes a fuel control valve 80 having a needle valve 79 driven by a solenoid coil 78, and is installed in the fuel supply pipe 73 of the fuel oil supply device S. This fuel control valve 85 is controlled by the microcomputer 65 of the electronic control device R, and is opened only during the fuel filling process, and is opened from the fuel oil supply device S side to the pump nozzle 1.
It acts to allow the flow of fuel oil to the side.
In this case, the solenoid coil 12 of the injector device T is energized only during injection.

The intake valve device
A hydraulic valve drive device 61 is installed to open and close the intake valve 3 using hydraulic pressure.
6 is opened and closed by the spring force of a valve spring 39 and the hydraulic pressure of a hydraulic valve drive device 61. The hydraulic valve drive device 61 includes an intake valve 3 in a cylinder body 42 fixed to the cylinder head 35 side by fixing bolts 59, 59, . . .
6 in the valve opening direction by hydraulic pressure, and a solenoid valve section 63 that controls the flow of hydraulic oil introduced into the working chamber 43 of the piston 44. This solenoid valve section 63 has almost the same configuration as the solenoid valve section 31 of the injector device T, and has an active core 47 driven by the attraction force of the solenoid coil 48 and a spool valve 45 disposed coaxially. And this spool valve 45,
A second spring 5 attached to the spool valve 45 side
1 and the active core 47 side, and the two land portions 45a,
45b, the hydraulic oil inlet 52 and the piston chamber introduction oil passage 5
3 and piston chamber discharge oil passage 54 as appropriate to move the piston 44 up and down.
It is designed to open and close the valve. That is, in this embodiment, the spring force of the first spring 50 is
The spring force is set to be larger than the spring force of the spring 51, and when the solenoid coil 48 is de-energized, the spool valve 45 is pushed down by the difference in the spring force between the first spring 50 and the second spring 51, and the piston chamber is closed. The introduction oil passage 53 and the piston chamber discharge oil passage 54 are made to communicate with each other to discharge the hydraulic oil from the working chamber 43 (hereinafter, the valve position of the spool valve 45 in this case will be referred to as the first valve position), and conversely, the solenoid coil 48 is energized, its suction force pulls up the active core 47 against the spring force of the first spring 50, and the spool valve 45 is pushed upward by the spring force of the second spring 51. The hydraulic oil inlet 52 and the piston chamber introduction oil passage 53
is brought into communication and the hydraulic oil is introduced into the working chamber 43 (hereinafter, the valve position of the spool valve 45 in this case will be referred to as the second valve position). Note that the stroke of the active core 47 is adjusted by the screwing amount of the adjusting bolt 49. In addition, leakage oil from the spool valve 45 is drained from the first discharge oil path 56 to the active core 4.
7 through the oil passage hole 64 provided in the second discharge oil passage 55.
leakage oil from the piston 44 is transferred from the third discharge oil path 57 to the hydraulic oil tank 77 side.
7 side, respectively.

Since the exhaust valve device Y has the same configuration as the intake valve device X, detailed illustration and explanation thereof will be omitted.

The electronic control device R includes a rotational phase angle sensor 6 mounted close to the flywheel 67 of the internal combustion engine 68.
6 and the signal from the rotational phase angle sensor 66 to set the energization start timing, energization cutoff timing, etc. of the solenoid coil 12 of the injector device T, the solenoid coil 48 of the intake valve device X, and the exhaust valve device Y. It has a microcomputer 65 that controls the amount and timing of fuel injection, the rotational speed of the internal combustion engine 68, and the timing of opening and closing the intake and exhaust valves.

Next, the operation of the electro-hydraulic control system for the internal combustion engine of the illustrated embodiment will be explained. When the internal combustion engine 68 is operated, first, the fuel oil in the fuel tank 71 is pressurized to an appropriate pressure by the fuel supply pump 69. from the fuel supply pipe 73 to the fuel control valve 80 of the fuel control device Q.
The fuel oil inlet 40 of the injector device T via
will be pumped to. Further, the hydraulic oil in the hydraulic oil tank 77 is pressurized to an appropriate pressure by the hydraulic oil supply pump 76 and is passed through the hydraulic oil supply pipe 74 to the hydraulic oil inlet 22 of the injector device T and the hydraulic oil inlet of the intake valve device X. 52 and the hydraulic oil inlet of the exhaust valve device Y (not shown)
They are each pumped to

The fuel oil pressure-fed to the fuel oil inlet 40 side of the injector device T is supplied from the fuel oil filling oil passage 23 into the plunger chamber 6 of the hydraulic servo mechanism 33. Further, the hydraulic oil forced to the hydraulic oil inlet 22 side is branched from the third hydraulic oil passage 34 to the nozzle valve seat insertion hole 17 and from the first hydraulic oil passage 25 to the servo piston chamber 5. Supplied.
If the solenoid coil 12 is now energized, the active core 9 is pulled upward by the attractive force of the solenoid coil 12, and the spool valve 7 is set to the first valve position. When the spool valve 7 is set to the first valve position, the first hydraulic oil passage 25 and the second hydraulic oil passage 26 communicate with each other, so the hydraulic oil inlet 2
2 to the hydraulic oil first oil passage 25 and the hydraulic oil second oil passage 2
Hydraulic oil is introduced into the servo piston chamber 5 through the servo piston chamber 5, and the plunger 3 is moved downward together with the servo piston 4 by the hydraulic oil pressure in the servo piston chamber 5, increasing the amount of fuel oil in the plunger chamber 6. The fuel is then injected into the cylinder from the nozzle ports 19, 19, . . . (fuel injection stroke, FIG. 1, position shown).

When the power to the solenoid coil 12 is cut off, the attraction force of the solenoid coil 12 disappears, so the active core 9 and the spool valve 7 are connected to the first spring 1.
4 and the second spring 15, the spool valve 7 is pushed downward, and the spool valve 7 is set to the second valve position. When the spool valve 7 is set to the second valve position, the second hydraulic oil passage 26 and the third hydraulic oil passage
The servo piston 4 is moved upward by the pressure of the fuel oil introduced into the plunger chamber 6 by pushing open the supply valve 21 from the fuel oil filling oil path 23, and the servo piston 4 The hydraulic oil in the plunger chamber 5 is discharged to the hydraulic oil tank 77 side, and at the same time, the plunger chamber 6 is filled with fuel oil (fuel filling process). By repeating this fuel injection stroke and fuel filling stroke, the internal combustion engine 68 is continuously operated.

In this case, the fuel supply pipe 73 of the fuel oil supply device S
Since the fuel control valve 80 is installed inside, the solenoid coil 12 is energized at the end of the filling stroke, that is, at the start of the injection stroke, and the solenoid coil 12 is energized at the end of the injection stroke (i.e., when the plunger 3 has moved down to the lower limit position). Even if the power to 12 is cut off (i.e.,
Since the fuel control valve 80 is closed until the start of the next filling (even if the injector device T is ready to fill fuel), the plunger chamber 6 is not filled with fuel oil, and therefore the plunger 3 and servo The piston 4 is held at the lower limit position. Therefore, even if the energization to the solenoid coil 12 is cut off at the end of the injection stroke, the plunger chamber 6 will not be filled with more fuel oil than necessary, and the solenoid coil 12 only needs to be energized during the actual injection. Since the energization time is shortened, solenoid coil 1
2 temperature rise can be suppressed.

The fuel injection amount is controlled by the microcomputer 65 by adjusting the energization cutoff time of the solenoid coil 12 and the opening timing of the fuel control valve 80 to change the fuel filling amount. That is, by lengthening the energization cutoff time and advancing the opening timing of the fuel control valve 80, the amount of fuel charged increases, and the amount of fuel injection increases accordingly.

The fuel injection timing is adjusted by controlling the start timing of energization of the solenoid coil 12 based on the signal from the rotational phase angle sensor 66. For example, when performing an advance angle operation, the energization start timing is advanced.

Further, the rotational speed of the internal combustion engine 68 is controlled by changing the time interval of the energization cycle to the solenoid coil 12. For example, when increasing the rotational speed, the time interval between energization cycles is reduced.

In this injector device T, since fuel oil with low viscosity (for example, high-quality oil such as light oil or kerosene) is used as the hydraulic oil for the hydraulic servo mechanism 33, the spool valve 7 or the hydraulic servo mechanism 33
The operating resistance is small, and the fuel injection characteristics can be controlled in a responsive manner to changes in the operating state of the internal combustion engine 68 (improved responsiveness).

In addition, in the illustrated embodiment, the leaked oil from the spool valve 7 is made to flow through the oil passage hole 11 provided in the active core 9 and discharged to the fuel tank 71 side. 9. That is, the temperature rise of the solenoid coil 12 can be suppressed, and thereby the suction force characteristics of the solenoid coil 12 can be maintained stably and favorably over a long period of time.

On the other hand, the solenoid coil 48 of the intake valve device X and the solenoid coil of the exhaust valve device Y (not shown)
is energized or de-energized depending on the operating stroke of the internal combustion engine 68. That is, the solenoid coil 48 of the intake valve device X is energized near the end of the exhaust stroke, and de-energized at the beginning of the compression stroke. That is, when the solenoid coil 48 is energized, the active core 47 is pulled upward by its suction force, and the spool valve 45 is set to the second valve position, so that hydraulic oil is introduced into the working chamber 43. The intake valve 36 is opened as the piston 44 moves downward. On the other hand, when the power to the solenoid coil 48 is cut off, the spool valve 45 is set to the first valve position, and the intake valve 36 is closed by the spring force of the valve spring 39.

Further, the solenoid coil of the exhaust valve device Y is energized near the end of the expansion stroke to open the exhaust valve, and is deenergized at the beginning of the suction stroke to close the exhaust valve.

Both the intake valve device There is little operating resistance due to the viscosity of the oil, and there is no rust or abnormal wear on the sliding parts due to contained moisture or mixed foreign matter, which makes the intake valve 36 and exhaust valve more suitable for the internal combustion engine 68. Opening/closing operations can be performed with good response depending on the operating state, and the intake characteristics and exhaust characteristics of the internal combustion engine 68 are improved.

Furthermore, in this electro-hydraulic control device, the structure of the solenoid valve section 31 of the injector device T, the structure of the solenoid valve section 61 of the intake valve device X and the structure of the solenoid valve section of the exhaust valve device Y are almost the same. Each part of the injector device T, intake valve device X, and exhaust valve device Y is compatible with each other, so the number of types of parts can be reduced, and the structure can be simplified and costs can be reduced.

Next, to explain the effects of the present invention, the electro-hydraulic control device for an internal combustion engine of the present invention has hydraulic oil supplied to the hydraulic servo mechanism of the injector device and the hydraulic valve drive device of the intake valve device and the exhaust valve device. Since the fuel oil injected into the cylinder from the injector device and the fuel oil injected into the cylinder are supplied from separate hydraulic sources, the hydraulic servo mechanism of the injector device, intake valve device, and exhaust valve are supplied regardless of the type of injected oil. As the hydraulic oil for the valve mechanism of the device, we use high-quality oil with an appropriate viscosity and low water content and foreign matter to reduce the viscous resistance of the hydraulic oil and prevent sliding due to the water content and foreign matter. Rust and abnormal wear on moving parts can be suppressed as much as possible.
The responsiveness of the injector unit and the intake/exhaust valve units is improved accordingly, and the injection characteristics and intake/exhaust characteristics of the internal combustion engine are improved.

Furthermore, since the hydraulic fluid for the injector device and the hydraulic fluid for the suction and exhaust valve devices are simultaneously supplied from one hydraulic source, hydraulic oil is supplied to the injector device and the suction and exhaust valve devices from separate hydraulic sources. There is also the effect that the structure of the entire device can be simplified and the cost can be lowered compared to the case where .

In addition, by providing a fuel control device that controls the amount of fuel oil supplied between the injector device and the fuel oil supply device, the time for energizing the solenoid coil of the injector device is shortened.
This also has the effect of suppressing performance deterioration due to temperature rise of the solenoid coil and maintaining good fuel injection characteristics over a long period of time.

[Brief explanation of drawings]

FIG. 1 is a system diagram of an electro-hydraulic control device for an internal combustion engine according to an embodiment of the present invention. 2... Nozzle valve, 12... Solenoid coil, 31... Solenoid valve section, 32... Injector section, 33... Hydraulic servo mechanism, 36...
...Intake valve, 48...Solenoid coil, 61...
Hydraulic valve drive device, 62... Valve mechanism section, 63...
... Solenoid valve unit, 65 ... Microcomputer, 68 ... Internal combustion engine, 69 ... Fuel supply pump, P ... Hydraulic oil supply device, Q ... Fuel control device, R ... Electronic control device, S ... Fuel Oil supply device, T... Injector device, X... Intake valve device, Y... Exhaust valve device.

Claims (1)

[Claims] 1. A fuel oil supply device S having a fuel supply pump 69 driven by an internal combustion engine 68, and a hydraulic oil supply pump 7 driven by the internal combustion engine 68.
6, and a hydraulic servo mechanism 3 for supplying fuel oil pressure-fed from the fuel oil supply device S.
3, an injector device T includes an injector unit 32 that increases pressure and injects from the nozzle valve 2, and a solenoid valve unit 31 that controls the flow of hydraulic oil that operates the hydraulic servo mechanism 33;
A fuel control device Q for controlling the supply amount of fuel oil supplied from the fuel oil supply device S to the injector device T side, a valve operating mechanism section 62 that drives the valve 36 to open and close by hydraulic pressure; Valve mechanism section 62
a hydraulically driven intake valve device an electronic control device having a microcomputer 65 that appropriately controls the solenoid coil 12 of the section 31, the solenoid coil 48 of the solenoid valve section 63 of the intake valve device X and the exhaust valve device Y according to the operating state of the internal combustion engine 68; An electro-hydraulic control device for an internal combustion engine, characterized by comprising: R.