JPH03281979A - Lubricating oil supply control unit - Google Patents

Abstract

PURPOSE:To control the supply of lubricating oil for an optimum amount by correcting basic valve opening signals calculated from the rotational speed of a compressor with detected signals for the temperature and the pressure of the lubricating oil, and sending driving pulse signals instructing a proper valve opening to a lubricating oil injection valve. CONSTITUTION:A compressed air way 17 is connected to an air blast valve 16 injecting fuel into a combustion chamber 2 together with compressed air, the outlet 24 of a vane type air compressor 23 is connected to the compressed air way 17, and a lubricating oil supply unit 34 is provided on the intake 28 of the air compressor 23, and when an electromagnetic lubricating oil injection valve in the supply unit 34 is opened, the lubricating oil conveyed through a lubricating oil path 15 is supplied to the air compressor 23 as spray. Where, a temperature sensor to detect the temperature of the lubricating oil flowing in the lubricating oil injection valve, a pressure sensor to detect the pressure of the lubricating oil, and a rotational speed sensor to detect the rotational speed of the air compressor 23 are provided respectively. And an ECU 36 is made to send the lubricating oil injection valve driving signals to give proper valve opening for a specified amount of the lubricating oil flow corresponding to the rotational speed of the air compressor 23.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fuel injection device for, for example, an internal combustion engine, and particularly to a barrel-type fuel injection device called an air blast valve that injects fuel into a combustion chamber of an internal combustion engine using compressed air. In a fuel injection device equipped with a fuel injection valve, as in the case of an air compressor for supplying compressed air to the air blast valve, a lubricating oil constant supply control device that measures and supplies lubricating oil to the air compressor. Regarding.

[Conventional technology]

Japanese Patent Publication No. 60-501963 describes a method and apparatus for atomizing fuel with compressed air and injecting it into the cylinders of an internal combustion engine using an air blast valve as described above.

Generally, in such fuel injection devices, a vane type air compressor is used to supply compressed air for fuel atomization, but when using a vane type air compressor, air intake is A compressed air passage that has a lubricating oil injection valve at its mouth, supplies some of the engine's lubricating oil to it, sends the lubricating oil in the form of a spray into the air compressor, and communicates from its discharge port to the air blast valve. A cooler and oil separator are installed to separate and recover lubricating oil from compressed air.

Conventionally, no careful consideration was given to the amount of lubricating oil supplied to the air compressor in such cases, and since the lubricating oil pump was driven by the engine itself, other conditions were ignored (for the time being, The higher the rotational speed of the engine and lubricating oil pump, the more lubricating oil is supplied to the air compressor.

[Problem to be solved by the invention]

If the opening area of the lubricating oil injection valve is constant, the amount of lubricating oil injected within a unit time is determined by the viscosity and pressure of the lubricating oil. The viscosity of lubricating oil changes depending on its temperature, and the temperature of lubricating oil increases (changes) depending on how the engine warms up.It is better to increase the amount of lubricating oil as the rotation speed increases, but Although the number is a factor that reflects the lubricating oil pressure, if the numerical values of conditions other than pressure, such as temperature (viscosity) and injection time, change significantly, the amount of lubricating oil injected for the same valve opening will change significantly. It's coming.

If the supply of lubricating oil becomes excessive and exceeds the separation and recovery capacity of the oil separator, the unrecovered lubricating oil will enter the air blast valve together with the compressed air. There is concern that oil deposits may occur, which may change the characteristics or cause failures.

Conversely, when the supply of lubricating oil is low, the air compressor may seize, the temperature of the compressed air may rise excessively, causing thermal deterioration of the air blast valve, or the fuel may heat up and evaporate, causing fuel injection problems. Problems also arise, such as the inability to accurately control the amount.

The present invention addresses these problems and aims to solve the problem by controlling the amount of lubricating oil supplied to the air compressor to an optimum value.

[Means to solve the problem]

In order to solve the above problems, the present invention includes a lubricating oil injection valve attached to an air compressor, a temperature sensor that detects the temperature of the lubricating oil entering the lubricating oil injection valve, and a pressure sensor that also detects the pressure. and a rotation speed sensor that substantially detects the rotation speed of the air compressor, the temperature and pressure of the lubricating oil detected by the temperature sensor, the pressure sensor, and the rotation speed sensor, and the rotation speed of the air compressor. and an electronic control device that receives each signal and sends a drive pulse signal to the lubricating oil injection valve to give an opening degree that brings about a predetermined amount of lubricating oil flow rate corresponding to the rotational speed of the air compressor. The present invention provides a lubricating oil quantitative supply control device with features.

[For production]

The lubricating oil injection valve attached to the air compressor should supply lubricating oil to the air compressor at a flow rate commensurate with the rotational speed of the air compressor. If only the lubricating oil is controlled, the desired flow rate cannot be obtained, and the amount of lubricating oil will be too much or too little.

The reason for this is that the lubricating oil flow rate changes greatly even with the same valve opening due to changes in viscosity caused by temperature changes in the lubricating oil. Therefore, in the present invention, the valve opening calculated from the rotation speed of the air compressor is In contrast, the temperature, which determines the viscosity of the lubricating oil, and the pressure of the lubricating oil, which is also a direct factor determining the lubricant flow rate of the injection valve, are detected by each sensor, and these signals are used to calculate the rotation speed. The electronic controller uses a drive pulse signal that commands the appropriate valve opening so that the air compressor is supplied with lubricating oil at just the right flow rate commensurate with the rotational speed. is sent to the lubricating oil injection valve.

〔Example〕

FIG. 1 shows the overall configuration of an internal combustion engine including an embodiment of the lubricating oil constant supply control device of the present invention.

In the figure, 1 is the internal combustion engine body, 2 is the combustion chamber, 3 is the piston, 4
is the intake passage, 5 is the intake valve, 6 is the exhaust valve, 7 is the intake surge tank, 8 is the cylinder head, 9 is the PCV passage, 10
1 is a cylinder block, 11 is an oil pan, 12 is a lubricating oil reservoir, 13 is an oil strainer, 14 is an oil filter element, and 15 is a lubricating oil discharge pipe, through which part of the lubricating oil pressurized by a lubricating oil pump (not shown) is supplied. , through the discharge pipe 15 towards the air compressor.

16 is an air blast valve that injects fuel into the combustion chamber 2 together with compressed air, 17 is a compressed air passage, and 18 and 19 are oil separators installed in two stages in the middle of the compressed air passage 17 to separate lubricating oil. is when the valves 20 and 21 are opened (when the engine is stopped, etc., the valves are opened by the control device described later).
, the lubricating oil returns to the lubricating oil reservoir 12 through a lubricating oil return passage 22 .

Reference numeral 23 denotes a vane type air compressor, the discharge port 24 of which is connected to the compressed air passage 17, and a cooler 25 is provided upstream of the oil separator 18. The compressed air is cooled by the fins of the cooler 25, and the lubricating oil particles (oil mist) contained therein are easily aggregated and separated from the air in, for example, cyclone-type oil separators 18 and 19. and remains at the bottom of the separator until valves 20 and 21 open.

Note that 26 is an eccentric rotor of the compressor 23, 27 is a vane, and 28 is a suction port.

29 is an air cleaner, and most of the air taken in through there is passed through the air flow meter 30, throttle valve 31,
It passes through the supercharger 32, is sent to the surge tank 7 as the intake air of the engine body 1, passes through the intake passage 4, and enters the combustion chamber 2 when the intake valve 5 is opened.

A part of the air sucked from the air cleaner 29 is diverted to the air passage 33 and sucked into the air compressor 23 from the suction port 28. A lubricating oil supply device 34 is provided at the suction port 28, and when the electromagnetic lubricating oil injection valve included therein is opened, an amount of lubricating oil (lubricating oil from the engine body 1) corresponding to the valve opening time is supplied. The pressurized lubricating oil sent through the passage 15 is supplied into the air compressor 23 in the form of a spray. This lubricating oil lubricates the sliding surfaces of the vanes 27 of the compressor 23 and the casing 35, and the like. The air compressed in the air compressor 23 passes through the compressed air passage 17, is cooled by the cooler 25 as described above, is stripped of lubricating oil by the oil recoverers 18 and 19, and then enters the air blast valve 16. When the air injection valve opens, the air blast valve 1 is
6 and injected in a required amount, the valve port is pushed open and the fuel is injected into the combustion chamber 2 of the internal combustion engine main body 1. The fuel spray is atomized by the expansion of the compressed air and mixed into the intake air drawn into the combustion chamber 2 from the intake passage 4 through the intake valve 5, and the formed air-fuel mixture is compressed by the rise of the piston 3. It is ignited by a spark plug (not shown) and combusts.

The air injection valve and fuel injection valve of the air blast valve 16 are electromagnetic valves, and opening and closing are controlled by an electronic control unit (ECU) 36. In the embodiment of the present invention shown in FIG. 1, the ECU 36 also controls the opening and closing of the injection valve of the lubricating oil supply device 34. For this purpose, in addition to the engine speed signal N1 from the engine speed sensor (not shown) in the engine body 1 and the battery voltage E, the EICo 36 also receives signals from the lubricating oil supply device 34 as shown in an enlarged view in FIG. A temperature signal T1 transmitted by a lubricating oil temperature sensor 37 and a pressure signal P transmitted by a lubricating oil pressure sensor 38 are input.

In FIG. 2, the lubricating oil supply device 34 is connected to the engine main body 10.
A lubricating oil pump 39 that receives pressurized lubricating oil from a lubricating oil pump (not shown) through a lubricating oil discharge pipe 15, an electromagnetic lubricating oil injection valve 40 that injects lubricating oil, and an air compressor that injects the injected lubricating oil. An outlet 41 leading to the suction port 28 of 23
has. The lubricating oil that has entered the passage 42 from the population 39 to the injection valve 40 comes into contact with a temperature sensor 37 and a pressure sensor 38 to have its temperature and pressure measured.
Enters 0. The lubricating oil injection valve 40 is connected to the ECU via the terminal 43.
When a pulsed drive signal is received from 36, lubricating oil is sprayed into the outlet 41 from the valve port 46, which is opened by the needle 45 which is pulled up by the solenoid 44 for the duration of the pulse signal, and is sucked. It enters the air compressor 23 together with air through the port 28 to lubricate the inside.

By the way, the amount of lubricating oil supplied from the lubricating oil supply device 34 to the air compressor 23 within a unit time, that is, the lubricating oil flow rate Q
should be increased or decreased in proportion to the rotational speed N of the engine body l, as shown in FIG. This is because the air compressor 23 is driven by the engine body 1, and its rotation speed is the same as the rotation speed N of the engine body 1, or is proportional to the rotation speed N of the engine body 1, so the rotation speed of the compressor 23 is This is because increasing or decreasing the flow rate Q of lubricating oil in accordance with the increase or decrease is the same as controlling it in accordance with the increase or decrease in the rotation speed N of the engine body 1. In this case, there is no problem in practice even if the control shown in FIG. 4 is performed in a stepwise manner without performing the strictly proportional control as shown in FIG. 3.

However, as mentioned earlier, when the lubricating oil flow rate Q is increased or decreased at a constant rate as shown in Figures 3 and 4 in response to changes in the engine speed N, the viscosity of the lubricating oil is Because it changes greatly with T, even though the lubricating oil pump's discharge pressure is proportional to the rotation speed when the viscosity is constant,
This alone cannot keep the relationship between the engine speed N and the lubricating oil flow rate Q constant under all conditions. Moreover, B
Even if the CU 36 sends a drive pulse to the lubricating oil injection valve 40 for the same amount of time, if the height (voltage value) of the pulse, that is, the battery voltage E, changes in magnitude, the response speed of the injection valve 40 will change. There is also the problem that this causes a difference in the actual lubricating oil flow rate Q.

Therefore, in the embodiment of the present invention, the lubricating oil flow rate Q is controlled by the control procedure shown in the flowchart of FIG. First, in 101, a signal of the rotation speed N of the engine main body 1 instead of the rotation speed of the compressor 23 is read from a rotation speed sensor (not shown) into the computer (CPU) of the ECU 36, and in 102, a signal of the rotation speed N of the engine main body 1 instead of the rotation speed of the compressor 23 is read into the computer (CPU) of the ECU 36, and in 102, a signal of the rotation speed N of the engine main body 1 instead of the rotation speed of the compressor 23 is read into the computer (CPU) of the ECU 36. Figure 3 or 4
The required lubricating oil flow rate Q corresponding to the rotational speed N at that time is determined by comparing with the map shown in the figure. Then, proceeding to step 103, the relationship between the pressure (hydraulic pressure) P and temperature (oil temperature) T that causes such a lubricating oil flow rate Q is measured in advance, and εCal is calculated.
Select a specific map like the one shown in Figure 6, which is set in the ROM in the 36, from among the many maps, and use it as an RA.
Let M memorize it.

Next, the oil temperature T and oil pressure P signals sent by the temperature sensor 37 and the pressure sensor 3B are read into the CPU at 104 and 105, compared with the map adopted at 103 (Fig. 6), and the lubricating oil is then Calculate the frequency T of the drive pulse signal to be sent to the solenoid 44 of the injection valve 40 (106
). As shown in the enlarged view of FIG. 6, the map records frequencies Tf corresponding to oil pressure P and oil temperature T. Basically, if the lubricating oil injection valve 40 is duty-controlled by the pulse of the frequency T calculated in this way, as shown in FIG. (lower row), the total valve opening time of injection 40 changes,
The lubricating oil flow rate Q can be made to almost match the required amount.

In the case of this embodiment, correction is also made for changes in the responsiveness of the injection valve 40 due to fluctuations in the battery voltage E. At 107 in FIG. 5, the battery voltage signal E is read into the CPU and stored in the ROM. The 8th set to
From the map shown in the figure, the pulse width (length) ti corresponding to the battery voltage E at that time is read at 108. In this map, corresponding numerical values are measured and recorded in advance, such as, for example, when the voltage E is 14V, the pulse width ti is 5ms.

A driving pulse having the frequency T and width t1 thus determined as shown in FIG. If the valve is turned on, the oil temperature T1 oil pressure P at that time
1 and the battery voltage E are taken into consideration, the lubricating oil is injected at an accurate target flow rate Q for the rotational speed N at that time, and the air compressor 23 is injected without excess or deficiency. can be lubricated, eliminating the conventional problems.

The present invention is not limited to the duty control as shown in FIG. 7, but also controls the opening and closing of the lubricating oil injection valve 40 by keeping the pulse frequency constant and changing only the pulse width τ as shown in FIG. A similar effect can also be obtained.

The control procedure in this case is based on the pulse width τ based on the oil pressure P and oil temperature T, rather than the map shown in FIG. 6, which is determined in step 103 of the flowchart shown in FIG. Use something that can be read. Then, the correction based on the battery voltage E at 108 is the basic pulse width, that is, the basic injection amount τ. A calculation is performed to multiply the battery voltage E by a correction value for the battery voltage E recorded separately in the map, and a pulse width T that matches the rotational speed N at that time is calculated.
1 or τ3, etc., and the lubricating oil injection valve 40 is driven to open and close accordingly.

〔Effect of the invention〕

According to the present invention, lubricating oil is accurately measured and supplied to the air compressor at a flow rate commensurate with its rotational speed, so there is no excess or shortage of lubricating oil, and this can be used, for example, as fuel for internal combustion engines. When used in an injection device, lubricant oil may be supplied in excess of the separation capacity of the oil separator installed upstream of the fuel injection device, causing damage to the fuel injection device, or the air compressor may be damaged due to lack of lubricant oil. There is no risk of burning or excessive rise in the temperature of the compressed air, causing various problems.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the overall configuration of an embodiment of the present invention, and FIG.
The figure is a sectional view showing an enlarged main part of the embodiment, FIGS. 3 and 4 are diagrams showing the target lubricating oil flow rate, and FIG. 5 is an example of the control procedure in the control device of the present invention. Flow chart, FIG. 6 is a diagram illustrating a control map built into the control device of the present invention, FIG. 7 is a diagram illustrating an example of a drive pulse signal sent to the lubricating oil injection valve of the present invention, FIG. FIG. 8 is a line diagram showing one of the control maps built into the control device in the embodiment of the present invention, and FIG. 9 is a line diagram showing another example of the drive pulse signal sent to the lubricating oil injection valve of the present invention. It is a diagram. DESCRIPTION OF SYMBOLS 1... Internal combustion engine body, 3... Piston, 5... Intake valve, 7... Surge tank, 9... PCv passage, 11... Oil pan, 13... Oil strainer, 14 ...Oil filter element, 15...Lubricating oil discharge pipe, 16...Air blast valve, 17...
compressed air passage, 18.19... oil separator, 20.
21... Valve, 22... Lubricating oil return passage,
23...Air compressor, 24...Discharge port, 25
...Cooler, 26...Rotor, 27...Vane,
28... Suction port, 29... Air cleaner, 30...
・Air flow meter, 31... Throttle valve, 2... Combustion chamber, 4... Intake passage, 6... Exhaust valve, 8... Cylinder head, 10... Cylinder block, 12... Lubricating oil reservoir, 32... Supercharger, 33... Air passage, 34... Lubricating oil supply device, 35... Casing, 36... Electronic control unit (ECU), 37... Temperature Sensor, 38... Pressure sensor, 39... Lubricating oil inlet, 40... Lubricating oil injection valve, 41... Outlet,
42... passage, 43... terminal, 44...
・Solenoid, 45...needle, 46...valve port.

Claims (1)

[Claims] A lubricating oil injection valve attached to the air compressor, a temperature sensor that detects the temperature of the lubricating oil entering the lubricating oil injection valve, a pressure sensor that also detects the pressure, and substantially the rotation speed of the air compressor. a rotational speed sensor that detects the temperature and pressure of the lubricating oil detected by the temperature sensor, the pressure sensor, and the rotational speed sensor, and the rotational speed of the air compressor; A lubricating oil constant supply control device comprising: an electronic control device that sends a drive pulse signal that provides an opening degree that provides a predetermined amount of lubricant flow rate corresponding to the rotational speed of the air compressor.