JPH07286529A - Lubricating oil pressure adjusting method according to load of supercharger and device thereof - Google Patents

Abstract

PURPOSE:To realize a lubricating oil pressure adjusting method according to the load of a supercharger and a device thereof, by which lubricating oil pressure decreases in the low rotating speed territory so as to increase the mechanical efficiency of the supercharger, and insures regular lubricating oil pressure in the high rotating speed territory. CONSTITUTION:The supercharger inlet of a lubricating oil line 4 toward the supercharger branched from a main engine lubricating oil line 5 is controlled by means of a flow adjusting valve with cylinder 10 communicated to the discharge air of the supercharger, so as to restrict the passage at low discharge air pressure, and enlarge the passage at high pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating oil pressure adjustment for improving the mechanical efficiency of a supercharger in a low rotation range.

[0002]

2. Description of the Related Art A conventional example will be described with reference to FIG. FIG. 4 is a diagram of a lubricating oil line of a conventional diesel engine supercharger. In the figure, the lubricating oil to the supercharger 1 is supplied by a lubricating oil line 4 branched from a lubricating oil line 5 of the main engine. That is, the orifice 2 or the pressure regulating valve 3 is provided at the inlet of the supercharger 1 from the lubricating oil line 4 to adjust the lubricating oil pressure. Next, the operation of the conventional example will be described. When the lubricating oil pressure is adjusted using the orifice, the orifice diameter is adjusted so that the specified lubricating oil pressure (about 1 kgf / cm ² ) is obtained at 100% load of the engine. Therefore, in the low rotation speed range, the lubricating oil flow rate is lower than in the high rotation speed range, and the lubricating oil pressure becomes higher than the specified pressure. When using a pressure regulating valve, the specified pressure is always maintained regardless of the rotation speed.

[0003]

In the prior art, the lubricating oil pressure becomes the specified pressure or higher in the low rotation speed range. Since the PV value (D is the bearing surface pressure, V is the shaft surface speed) is small in the low rotation range, lubricating oil having a specified pressure is not required. If more lubricating oil is supplied in the low speed range, mechanical efficiency will decrease. Therefore, in the conventional technique, as described above, the lubricating oil pressure is unnecessarily high, so that there is a problem that the mechanical efficiency in the low rotation range is lowered.

The object of the present invention is to eliminate the above-mentioned problems, reduce the lubricating oil pressure in the low speed region, increase the mechanical efficiency of the supercharger, improve the combustion in the low load region, and improve the normal in the high speed region. The present invention provides a method and apparatus for adjusting the lubricating oil pressure according to the load of the supercharger, in which the reliability of the bearing is not impaired because the lubricating oil pressure is secured.

[0005]

A method of adjusting a lubricating oil pressure according to a load of a supercharger according to a first aspect of the present invention is a flow control valve 10 provided in a lubricating oil line 4 branched from a lubricating oil line 5 of a main engine.
Is controlled by the discharge air pressure 11 of the supercharger, and the passage area of the control valve 10 is narrowed in the low rotation range of the supercharger to keep the lubricating oil pressure of the supercharger at the minimum necessary pressure, while increasing the high load. The region is characterized by opening the lubricating oil control valve to ensure a regular lubricating oil pressure.

The lubricating oil pressure adjusting device according to the load of the supercharger of the second invention is installed in the lubricating oil line 4 for lubricating the supercharger 1 branched from the lubricating oil line 5 of the main engine, and in the oil line. It is characterized by including a flow rate adjusting valve 10 capable of varying the area of the oil passage, and a pipe line 11 for guiding the discharge air pressure of the supercharger into the cylinder of the flow rate adjusting valve.

[0007]

When the discharge air pressure of the supercharger is low, that is, in the low rotation speed range, the low discharge air pressure acts on the pneumatic cylinder to reduce the lubricating oil passage area to the supercharger, so that the supercharger is supplied to the supercharger. Since the lubricating oil pressure is reduced, the minimum required amount of lubricating oil flows, improving the mechanical efficiency of the turbocharger. In the high discharge air pressure, that is, in the high rotation range, the high discharge pressure acts on the pneumatic cylinder to increase the cross-sectional area of the lubricating oil passage to the supercharger. Sex is not impaired.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment according to the present invention will be described with reference to FIGS. 1 is a diagram of a lubricating oil line of a supercharger according to a first embodiment of the present invention, FIG. 2 is a sectional view of a needle valve with a cylinder according to a first embodiment of the present invention, and FIG. FIG. 4 is a diagram showing a relationship between a discharge pressure, a supercharger lubricating oil pressure, and a clearance area between a valve and a valve seat in one embodiment. In the figure, a cylinder needle valve 10 is provided at the inlet of the supercharger 1 of the lubricating oil line 4 to the supercharger 1 branched from the main oil line 5. In order to control the throttle of the needle valve with cylinder 10, the air discharged from the supercharger 1 is guided to the needle valve with cylinder 10 by an air line 11. FIG. 2A is a diagram of a state of the needle valve with cylinder 10 in a low rotation range. Valve stem 20
A valve 20b is attached to one side and a piston 20a is attached to the other side. Needle valve with cylinder 10 has valve rod 2
0, a casing 24, a cylinder 22, a spring 21, and stoppers 23 and 31. The lubricating oil line 4 is connected to the casing 24. Cylinder 22 spring 2
The discharge air line 11 is connected to the port 26 on the side opposite to 1. FIG. 2B is a sectional view showing a state of the needle valve with cylinder 10 in a high rotation range. The piston 20a is located between the stopper 23 and the stopper 31.

Next, the operation of the first embodiment will be described. Since the discharge air pressure guided to the port 26 is low in the low rotation range, the valve rod 20 is pushed toward the valve seat 25 by the spring 21 via the piston 20a. The piston 2 is shown in FIG.
0a hits the stopper 23. At this time, the gap 40 between the valve seat 25 and the valve 20b becomes the minimum, and the required minimum lubricating oil pressure in the low rotation range is obtained. Since the pressure of the discharge air 30 guided to the port 26 is high in the high rotation range, the piston 20a is moved to the spring 2
The push valve 20b moves away from the valve seat 25 against the force of 1, and the gap 40 between the valve seat 25 and the valve 20b becomes large (the cross section of the lubricating oil passage becomes large), and the lubricating oil pressure after passing through the valve is in the low rotation range. It will be higher than when. When the discharge air pressure further increases, the piston 20a finally hits the stopper 31 and the valve seat 25
The gap 40 between the valve and the valve 20b does not expand any further.

FIG. 3 shows the relationship between the discharge pressure and the clearance area F between the valve seat 25 and the valve 20b and the lubricating oil pressure P _{LO at} the inlet of the supercharger 1. When the discharge pressure is 0, the piston 20b hits the stopper 23 and the clearance area between the valve seat 25 and the valve 20b becomes the minimum value F ₁ . When the discharge pressure reaches P ₁ , the piston 20a hits the stopper 31 and the clearance area between the valve seat 25 and the valve 20b reaches its maximum value F ₂ . The lubricating oil pressure P _LO at the inlet of the supercharger becomes a normal pressure above the discharge pressure P ₁ and hardly changes. The characteristics can be changed by changing the shape of the needle valve.

[0011]

The discharge air pressure of the supercharger changes according to the rotation speed of the supercharger, and the lubricating oil supply pressure to the supercharger changes accordingly. In the low rotation range, the lubricating oil pressure decreases and the supercharger decreases. The mechanical efficiency of the engine is increased, the rotation speed of the supercharger is increased, and the discharge pressure is increased, thereby improving the combustion of the engine in the low load region. The reliability of the bearing is not impaired because the conventional regular lubricating oil pressure is secured in the high rotation range.

[Brief description of drawings]

FIG. 1 is a diagram of a lubricating oil line of a supercharger according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a needle valve with cylinder according to a first embodiment of the present invention.

FIG. 3 is a diagram showing a relationship between a discharge pressure of a supercharger, an inlet pressure of lubricating oil of the supercharger, and a clearance area between a valve seat and a valve according to the present invention.

FIG. 4 is a diagram of a lubricating oil line of a turbocharger of a conventional diesel engine.

[Explanation of symbols]

1 ... Supercharger, 2 ... Orifice, 3 ... Throttle valve, 4 ... Lubricating oil line, 5 ... Lubricating oil line, 11 ... Air line, 10 ...
Cylinder needle valve (flow rate adjusting valve), 20 ... valve rod, 2
0a ... Piston, 20b ... Valve, 21 ... Spring, 22 ... Cylinder, 23 ... Stopper, 24 ... Casing, 25 ... Valve seat, 26 ... Port, 31 ... Stopper, 40 ... Gap between valve and valve seat.

Claims (2)

[Claims] 1. A supercharger in which a flow control valve (10) provided in a lubricating oil line (4) branched from a lubricating oil line (5) of a main engine is controlled by a discharge air pressure (11) of the supercharger. In the low rotation range, the passage area of the control valve (10) is throttled to keep the supercharger lubricating oil pressure at the minimum necessary pressure, while in the high load range, the lubricating oil control valve is opened to maintain the normal lubricating oil pressure. A method for adjusting the lubricating oil pressure according to the load of the supercharger, which is characterized by ensuring. 2. A lubricating oil line (4) for lubricating a supercharger (1) branched from a lubricating oil line (5) of a main engine, and a flow rate adjusting valve installed in the oil line and capable of varying an oil passage area. A lubricating oil pressure adjusting device according to the load of the supercharger, comprising: (10) and a pipe line (11) for guiding the discharge air pressure of the supercharger into the cylinder of the flow control valve.