JPS6312813A - Oil supplying system for internal combustion engine - Google Patents

Abstract

PURPOSE:To improve the low temperature starting performance of an internal combustion engine, by providing a means for limiting an oil flow rate and a means for heating the oil at the suction side of an oil pump to heat efficiency only a small amount of oil to lower viscosity of the oil. CONSTITUTION:Oil in a tank 1 is supplied to the respective parts of an engine 5 through a strainer 2 and a pipe 3 from a pump 4 and returned to the tank 1. In this constitution, means, such as a shut valve 6, for limiting an oil flow rate is provided in the suction side pipe of the pump 4, and a heater 7 is provided in a pipe line between the shut valve 6 and the pump 4. In case that cooling water temperature sensed by a sensor S is below the preset level, electricity is sent to VSV valve 9 by a controller 11 so as to actuate vacuum in a diaphragm chamber 8 for shutting said pipe 3 by said shut valve 6, and at the same time electricity is sent to the heater 7. Thereby, only a small amount of oil is heated efficiency to lower viscosity of the oil.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an oil supply system for improving the starting performance of an internal combustion engine, particularly a diesel engine, at low temperatures.

[Conventional technology and its problems]

Conventional diesel engines have poor starting characteristics at low temperatures,
It takes a considerable amount of time to obtain a stable rotational speed. One of the reasons for this is thought to be that the viscosity of engine oil increases significantly at low temperatures, which significantly increases the driving resistance of the oil pump.

[Means for solving problems]

The purpose of the present invention is to solve the problems in the conventional technology, and by keeping the viscosity of the oil sucked into the oil pump low during cold start, the drive resistance of the oil pump is reduced, and the engine runs stably. This shortens the time it takes to reach .

That is, this object is to provide an oil for an internal combustion engine, which is characterized in that a means for restricting the flow rate of oil and a means for heating the oil are provided on the suction side of an oil pump in a circulation system that supplies oil to the internal combustion engine. This is achieved through a feeding system.

This system will be explained based on a typical pipe diagram of the present invention shown in FIG.

Oil for engine lubrication is stored in an oil tank 1, passes through a strainer 2 and a strainer pipe 3 under the action of an oil pump 40, lubricates each engine part 5, and then returns to the oil tank 1 again to repeat a circulation cycle. Note that 20 is a relief valve for bypassing oil when the pressure on the discharge side of the oil pump 4 increases excessively.

As mentioned above, when the engine is started at a low temperature, the viscosity of the oil is high, so the load on the oil pump 4 increases, the engine is not sufficiently lubricated, and it takes a considerable amount of time to reach a predetermined stable engine speed. was. In order to solve this problem, in the present invention, the suction side of the oil pump 4 (
An oil flow rate restricting means such as a shut valve 6 is provided in the pipe line on the upstream side, and a heater 7 is further installed in the pipe line between the shut valve 6 and the oil pump 4.

The shaft valve 6 has a diaphragm chamber 8 as shown in the figure.
while the diaphragm chamber 8 is connected to the lever 12 connected to the output side of the ? Under the control of the ■S■ valve 9, which will be described later, is controlled by the tillia2S 11.
9, operated by pressure supplied from a vacuum tank 10;
Move the shirt 1 to valve 6 via the lever 12 to open the pipe 3.
is configured to block.

As shown in FIG. 2, the structure of the VS■ valve 9 includes an E boat 51 communicating with the diaphragm chamber 8, and a vacuum tank 10.
F boat 52 that communicates with the air, G port 53 that communicates with the atmosphere.
It has three openings.

In the illustrated state, the E-boat 51 communicates with the internal opening of the G-boat 53 inside the valve 9 through the gap at the lower end of the plunger 54, but the internal opening of the F-boat 52 is blocked by the upper end of the plunger 54. Closed. This makes the diaphragm chamber 8 equal to atmospheric pressure.

A coil 56 is provided surrounding the plunger 54, and is configured to pull down the plunger 54 against the force of a spring 55 when energized.

Therefore, when the coil 56 is energized, the plunger 54 moves downward away from the internal opening of the F port 52 to close the internal opening of the G boat 53 and at the same time opens the internal opening of the F boat 52 to communicate with the E port 51. . This makes the diaphragm chamber 8 equal to the negative pressure within the vacuum tank 10.

With the above configuration, the pressure within the diaphragm chamber 8 can be switched between negative pressure and atmospheric pressure depending on whether or not the coil 56 is energized.

Next, the operation of the system shown in FIG. 1 will be explained. When the temperature of the cooling water detected by the water temperature sensor S is below a predetermined temperature (for example, -20°C), when a key signal is input to the controller 11 by inserting the engine key, the controller 11
The coil 56 of the SV valve 9 is energized by a command from the SV valve 9, negative pressure is applied to the diaphragm chamber 8 by the mechanism described above, and the shaft valve 6 shuts off the vibrator 3. At the same time, the heater 7 is also energized and the oil near it is heated. During cracking by the starter, only a small amount of oil blocked by the shaft valve 6 is efficiently heated and sucked into the oil pump 4 in a reduced viscosity state, allowing the oil pump to operate with less driving resistance. . When the engine starts and the starter is stopped, the stop signal is input to the controller 11, ■ energization to the SV valve 9 and heater 8 is stopped, the shaft valve 6 is opened, and the oil is transferred from the oil tank 1 to the vibrator 3 as usual. The oil is sucked into the oil pump 4 through the oil pump 4 and begins to circulate to each part 5 of the engine. The relationship between these signals is shown in the diagram of FIG.

In addition, from the viewpoint of safety, it is preferable that the heater 7 be made of a PTC element, which has a low electrical resistance at low temperatures and instantly raises the temperature, and as the temperature rises, the resistance value increases and the amount of current decreases. . Power for operating this system is also supplied by a battery 13.

〔Example〕

FIG. 4 shows a system according to a second embodiment of the present invention. In this example as well, a heater and flow rate limiting means are provided in the pipe line just before the suction side of the oil pump, but in order to simplify the structure, the shaft valve 6 as the flow rate limiting unit in the system shown in Figure 1 is replaced. A metal mesh 16 is used. Other corresponding parts are designated by the same reference numerals as in FIG. This principle is basically the same as the former, and the viscosity of the oil changes greatly depending on the temperature, that is, at low temperatures, the viscosity is high and the 1ffi excess resistance against the metal mensch 16 is large, so the flow rate decreases. This method takes advantage of the fact that as the flow rate increases, the viscosity gradually decreases, the passage resistance also decreases, and the flow rate increases.

To explain this effect, when both a key signal and a water temperature signal below a predetermined temperature are input to the controller ti at the same time, the heater 7 (preferably composed of a PTC element) is connected to the battery 1.
3 is applied, raising the temperature of the oil in its vicinity. When the starter starts, the oil whose viscosity has been reduced by heating is easily sucked into the oil pump 4 and circulates through the pipe with low driving resistance. While the oil temperature is low, the flow rate passing through the metal mesh 16 is limited, so it can be efficiently heated by the heater 7, and as the oil temperature rises, the passage resistance decreases, so gradually The flow rate increases and the desired lubrication effect can be achieved.

FIG. 5 shows a third embodiment of the system of the present invention. In this example, a metal mesh is used as the flow rate restricting means as in the case of the second embodiment, but the structure in combination with the heater is further devised. That is, the metal mesh 26 is installed inside the strainer pipe 3 on the suction side of the oil pump, and the metal mesh 26 is surrounded by a heater. A bypass passage 14 is provided with a PTC element (preferably a PTC element).

To explain the operation of this system, at startup, both the key signal and the water temperature signal lower than a predetermined temperature are sent to the controller 1 at the same time.
1, power from the battery 13 is applied to the heater 7. When the starter starts, the oil has a high viscosity due to its low temperature, so it is difficult for it to pass through the metal mesh 26 in the pipe, so it mainly bypasses the bypass passage 14 and is heated by the heater 7. The oil is then sucked into the oil pump 4. Therefore, at the time of starting the engine, oil whose viscosity has been reduced due to heating is circulated through the pipes, reducing the driving resistance of the oil pump and making it possible to start the engine smoothly. When the engine rotation becomes stable and the oil temperature rises, the resistance to passing through the metal mesh 26 decreases, so the amount of oil passing through the metal mesh 26 increases rather than through the bypass passage 14.
It becomes a steady state. At this point, power supply to the heater 7 is stopped.

According to the third embodiment, compared to the second embodiment, it is possible to prevent troubles due to oil shortage immediately after starting when the oil temperature is low, and the reliability of the system is improved.

〔Effect of the invention〕

As described in detail above, according to the present invention, the oil flow rate limiting means and the oil heating means are provided on the suction side of the oil pump of the oil circulation system for the internal combustion engine, and the oil flow rate limiting means and the oil heating means are provided on the suction side of the oil pump of the oil circulation system for the internal combustion engine, and the activate the means,
Since a small amount of oil is efficiently heated to lower its viscosity and then supplied to the oil pump, the drive resistance of the pump is reduced and smooth engine starting is possible.

If a PTC element is used as a heating means, rapid heating is possible and overheating of the heater can be prevented, improving safety. Further, if a fixed metal meningle is used as the oil flow rate restricting means, the structure becomes simple and there is an advantage that the flow rate can be self-controlled in accordance with the oil pump.

[Brief explanation of drawings]

Figure 1 shows a typical oil v+! of the present invention! A schematic diagram of the ring system; Fig. 2 is a diagram showing the relationship of each signal in the system of Fig. 1; Fig. 3 is a sectional view showing the structure of the ■S■ valve used in the system of Fig. 1; The figure is a schematic diagram of a system according to a second embodiment of the present invention, and FIG. 5 is a schematic diagram of a system according to a third embodiment of the present invention. - Oil tank 2 - Strainer 3 - Strainer vibe 4 - Oil pump 5 - Engine parts 6 - Shut valve 7 - Heater 8 - Relief valve 9 - VSV valve 1 - Vacuum tank 11 - Controller 12 - Lever 13--Battery 14-Bypass passage 16.26--Metal mesh 51-G boat 52-F boat 5:3-G boat 54-Plunger 55-Spring 56--Coil Atmosphere Figure 3 Figure 4

Claims (1)

[Scope of Claims] 1. An internal combustion engine characterized in that, in a circulation system that supplies oil to the internal combustion engine, means for restricting the flow rate of oil and means for heating the oil are provided on the suction side of the oil pump. oil supply system. 2. The oil supply system for an internal combustion engine according to claim 1, wherein the oil heating means is provided between the oil flow rate limiting means and the oil pump. 3. The oil supply system for an internal combustion engine according to claim 1, wherein the oil heating means is provided in an oil circulation system in parallel with the oil flow rate limiting means. 4. The oil supply system for an internal combustion engine according to any one of claims 1 to 3, wherein the oil flow rate restricting means is variable. 5. The oil supply system for an internal combustion engine according to any one of claims 1 to 3, wherein the oil flow rate restricting means is of a fixed type. 6. The oil supply system for an internal combustion engine as set forth in any one of claims 1 to 5, wherein the oil heating means is a PTC heater.