JPH01285614A - Forced lubricating device for engine and the like - Google Patents

Abstract

PURPOSE:To enable the sudden rise of an oil temperature during the starting by a method wherein during the low temperature starting of an engine, lubricating oil is guided to the cylinder and piston side from the crank chamber side through a bypass oil passage, and the heat of a part heated to a high temperature relatively rapidly is absorbed. CONSTITUTION:In the starting of an engine, when an engine is in a cold state and a lubricating oil temperature is low and thus viscosity of the lubricating oil is increased, the delivery pressure of an engine-driven oil pump 2 is increased to a value higher than a given value. Thereby, a relief valve 7 is opened widely, a large quantity of the lubricating oil passes a bypass oil passage 3, and injected from terminal ends 4... toward the interior of a cylinder 6. After the lubricating oil injected in the cylinder 6 absorbs heat from the cylinder 6 and a piston, not shown, both heated by combustion to increase temperature, it is returned to an oil pass after the passage of it through a crank chamber 5. When an oil temperature is increased and kept at a stable value, viscosity of the lubricating oil is decreased, and the opening of a relief valve 7 is decreased.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a forced lubrication system for engines, compressors, etc., and more particularly to a forced lubrication system for engines, etc. that allows the oil temperature to rapidly rise at the time of startup. It is.

<Prior art> Generally, in forced lubrication systems for engines, compressors, etc., lubricating oil is pumped up from an oil pan using an oil pump, and the pressure oil discharged from the oil pump is adjusted to a predetermined pressure using a pressure regulating valve or relief valve. The oil is supplied to each lubricating part. The pressure regulating valve or relief valve described above maintains the internal pressure of the oil gear at a predetermined pressure by removing a portion of the pressure oil from the oil gear through which the pressure oil discharged from the oil pump flows, and the extracted pressure oil is returned directly to the oil pan. has been done.

In addition, the terminal end of one of the branch oil gears branched from the main oil gear gallery that distributes the pressure-regulated pressure oil is opened from the crank chamber side into the cylinder, and in particular, the sliding contact between the cylinder and the piston skirt is There are things that strengthen the lubrication of the parts.

<Problems to be Solved by the Invention> In the conventional forced lubrication systems for engines, etc., as described above, when the lubricating oil is in the engine, it is heated due to combustion, and when the lubricating oil is in the engine, it is The heat dissipation to and the above heat generation are in equilibrium and stable. Until the oil temperature stabilizes, the viscosity of the lubricating oil is high and the discharge pressure of the oil pump increases, so a large amount of lubricating oil is extracted from the pressure regulating valve or relief valve and returned to the oil pan without serving any purpose. As a result, the amount of oil supplied from the oil gear to each lubricating part tends to be insufficient. As a result, oil is more likely to run out, especially when starting an engine that has been out of operation for a long time. Piston seizure due to piston scuffing (viston scuff)
There is a high possibility that this will occur.

In order to solve these problems, the most effective way is to quickly raise the oil temperature at startup and stabilize the oil temperature within a short period of time.

The terminal end of one of the branch oil gears branched from the main oil gear gallery that distributes the pressure-regulated pressure oil is opened from the crank chamber side toward the inside of the cylinder. In conventional systems that enhance lubrication, a portion of the pressure oil is supplied between the cylinder and piston at the same time as the engine starts, which prevents the occurrence of piston scuff compared to systems that do not have such a branch oil gear rally. It will be advantageous at the top.

However, in order to prevent excessive cooling after the oil temperature has stabilized, the amount of oil in this branch oil gear is set to the amount required after the oil temperature has stabilized. There is no change in the fact that the amount of oil supplied to the oil gear is less than the required amount of oil, and this is not satisfactory in terms of preventing the occurrence of piston scuff.

Conventionally, in order to solve this problem, the circulation of the coolant is stopped until the coolant temperature rises to a predetermined value, and the temperature of the aircraft body such as the engine and the coolant temperature are rapidly raised to lower the oil temperature. Attempts have also been made to make the rise steeper.

In this case, although the oil temperature rise characteristics are considerably improved, the reality is that only unsatisfactory results are obtained.

The present invention has been made in consideration of the above-mentioned circumstances, and an object of the present invention is to provide a forced lubrication device for an engine or the like that allows the oil temperature to rapidly rise at the time of startup.

<Means for Solving the Problems> In order to achieve the above object, the forced lubrication system for an engine, etc. according to the present invention, for example, as shown in FIG. 1 or FIG. A bypass oil passage 3 is provided in the oil pump 2 provided in the oil pump 2 to lead out a portion of the lubricating oil discharged from the oil pump 2, and a terminal end 4 of the bypass oil passage 3 is opened from the crank chamber 5 side into the cylinder 6. In addition, variable flow valves 7 and 8 are provided in the bypass oil passage 3 to increase the flow rate when the viscosity of the lubricating oil is higher than a predetermined value.
It is characterized by the intervention of

The variable flow rate valves 7 and 8 may be configured such that the flow rate becomes large when the viscosity of the lubricating oil is high.
As shown in the figure, the oil pan 10 may be configured with a relief valve that adjusts the oil pressure of pressure oil supplied to each part of the aircraft body 1, or as shown in FIG. The control circuit 11 may be configured with a shutoff valve 8 that opens when the oil temperature in the interior is below a predetermined value, or may be controlled when the cooling water temperature, the aircraft body temperature, etc. are below a predetermined value instead of the oil temperature. The circuit can be configured with a shutoff valve that opens and closes.

<Function> In the forced lubrication system for engines, etc. of the present invention, when the viscosity of the lubricating oil is high, the flow rate of the variable flow valve increases, and a large amount of lubricating oil flows from the crank chamber side into the cylinder through the bypass oil passage. is discharged.

While lubricating between the cylinder and piston, a large amount of lubricating oil is heated by absorbing heat from the cylinder and piston that are heated due to combustion or air compression, and is returned to the oil pan. This will speed up the rise in temperature.

(Example> Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a lubricating oil circuit diagram of essential parts of a forced lubrication system for an engine according to an embodiment of the present invention.

The forced lubrication system for this engine includes an oil pump 2 provided at the front side of the crankcase 12 that supplies lubricating oil from an oil pan 10 formed continuously below the crank chamber 5 in the fuselage 1.
Pressure oil can be pumped out and supplied to parts of the fuselage 1 that require lubrication, that is, each lubricating part, via the oil gear gallery 13.

A relief valve 7 is connected to a starting end portion of the oil gear rally 13, and a terminal end 4 of a bypass oil passage 3 led out from a drain lower a of the relief valve 7 is opened toward the inside of the cylinder 6 from the crank chamber 5 side.

In this forced lubrication system for an engine, when the lubricating oil temperature is low at the time of starting the engine, etc., and therefore the viscosity of the lubricating oil is high, the discharge pressure of the oil pump 2 becomes higher than a predetermined value, and the relief valve 7 opens wide. A large amount of lubricating oil is injected from the crank chamber 5 side into the cylinder 6 through the bypass oil passage 3. The lubricating oil injected into the cylinder 6 absorbs heat from the cylinder 6 heated by combustion and a piston (not shown), and then passes through the crank chamber 5 and returns to the oil pan. Therefore, at the time of starting, a part of the lubricating oil that was conventionally returned to the oil pan 10 without playing any role can form an oil film between the cylinder 6 and the piston to lubricate it. By being heated, the temperature of the lubricating oil can be rapidly raised. When the oil temperature rises and becomes stable, the viscosity of the lubricating oil becomes lower than a predetermined value, and the flow rate of the relief valve 7 is reduced. This reduces the amount of heat absorbed from the cylinder 6 and the piston, making it possible to prevent an excessive rise in oil temperature and an increase in oil consumption.

FIG. 2 is a lubricating oil circuit diagram of a main part of a forced lubrication system for an engine according to another embodiment of the present invention.

The forced lubrication system for this engine includes a bypass oil passage 3 branched from the starting end of an oil gear gallery 13 connected to a discharge port of an oil pump 2, a cutoff valve 8 interposed in the bypass oil passage 3, and an oil pan 10. The control circuit 1 includes an oil temperature sensor 14 that detects the oil temperature in the
1 opens the cutoff valve 8 when the oil temperature in the oil pan 10 detected by the oil temperature sensor 14 is below a predetermined value, and closes the cutoff valve 8 when it exceeds the predetermined value.

The rest of the structure is the same as that of the above-described embodiment, except that the drain oil from the relief valve 7 is returned to the oil pan lO as in the conventional case.

In this embodiment, the viscosity of the lubricating oil is represented by the oil temperature, which has a certain relationship with it, and when the oil temperature is below a predetermined value, that is, when the viscosity of the lubricating oil is below a predetermined value, a shutoff valve is activated. 8 is opened, and a portion of the pressure oil discharged from the oil pump 2 can be applied to the cylinder 6 and the piston to strengthen the lubrication between them, and the heat of the cylinder 6 and the piston can be absorbed into the lubricating oil to lower the lubricating oil temperature. can accelerate the start-up.

<Effects of the Invention> According to the forced lubrication device for an engine, etc. of the present invention, as explained above, when the viscosity of the lubricating oil is higher than a predetermined value, such as when starting an engine, or when the lubricating oil temperature is a predetermined value, When the temperature is lower than The oil temperature can be raised rapidly, and by pouring pressure oil onto the cylinder and piston, it is possible to lubricate the space between them, and the gap between the cylinder and piston can be sufficiently maintained even when starting up after a long period of rest. Can be lubricated to prevent piston scuff from occurring. Moreover, when the viscosity of the lubricating oil decreases or the oil temperature exceeds a predetermined value, the flow rate of the bypass oil path is throttled or shut off, which can reduce excessive oil temperature rise and oil consumption. be.

[Brief explanation of the drawing]

FIG. 1 is a lubricating oil circuit diagram of the main parts of a forced lubrication system for an engine according to an embodiment of the present invention, and FIG. 2 is a lubricating oil circuit diagram of the main parts of a forced lubrication system for an engine according to another embodiment of the invention. It is a circuit diagram. ■... Airframe, 2... Oil pump, 3... Bypass oil 4... End of bypass oil passage 3, 5... Crank chamber, 6... Cylinder, 7... Relief valve ( 8... Shutoff valve (variable flow rate valve). Patent applicant Kubota Iron Works Co., Ltd. Figure 1 Figure 2

Claims (1)

[Claims] 1. Oil pump (
2) is provided with a bypass oil passage (3) that leads out a portion of the lubricating oil discharged from the oil pump (2), and the terminal end (4) of this bypass oil passage (3) is connected from the crank chamber (5) side to the cylinder ( 6) It is characterized by opening inward and interposing variable flow rate valves (7) and (8) in the bypass oil passage (3) that increase the flow rate when the viscosity of the lubricating oil is higher than a predetermined value. Forced lubrication equipment for engines, etc.