JPH0618015Y2 - Lubricator for 4-cycle engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a lubrication device for a four-cycle engine.

[Conventional technology]

In a lubrication device for a four-cycle engine, a branch portion is generally provided in a main passage extending from an oil pump, and lubricating oil pumped from the oil pump through the branch portion is fed to a crankshaft system and a cylinder head system. It is distributed to each of them.

FIG. 3 conceptually shows such a lubricating device. In this lubricating device, the lubricating oil in the oil pan 1 is sucked by the oil pump 3 via the strainer 2 and is pumped from the oil pump 3 to the main passage 4. The lubricating oil pumped to the main passage 4 is distributed and supplied to the crankshaft system 6 and the cylinder head system 7 after passing through the oil filter 5 and the branch portion 9. The lubricating oil supplied to the crankshaft system 6 lubricates the bearings of the crankshaft, the bearings of the connecting rod, the cylinder, etc., and the lubricating oil supplied to the cylinder head system 7 is used for the bearings of the rocker arm and the camshaft. After lubricating the bearings and the like, they are returned to the oil pan 1. Incidentally, reference numeral 8 in FIG.
Is a jet that limits the flow rate of the lubricating oil supplied to the cylinder head system 7, and causes mechanical loss in the valve operating mechanism and the oil pan 1 caused by a large amount of lubricating oil supplied to the cylinder head system 7. It is intended to prevent problems such as shortage of the amount of stored lubricating oil.

By the way, in a normal four-cycle engine, the cylinder head system 7 is arranged at a position sufficiently higher than the crankshaft system 6.

Therefore, under a specific condition, that is, when the temperature of the lubricating oil is high and the oil pump 3 is in the low rotation state, in other words, the viscosity of the lubricating oil is lowered and the oil pump 3 is
When the discharge pressure and the discharge flow rate of the cylinder head are small, sufficient hydraulic pressure to supply the cylinder head system 7 at the branch portion 9 is not ensured, so that most of the lubricating oil is supplied to the crankshaft system 6, There was a possibility that the required amount of lubricating oil could not be supplied to the system 7.

[Purpose of device]

In view of the above situation, an object of the present invention is to increase the supply amount to the cylinder head system without increasing the supply amount to the cylinder head system when the temperature of the lubricating oil is low, and to increase the supply amount to the cylinder head system when the temperature of the lubricating oil is high. The object of the present invention is to provide a lubrication device for a four-cycle engine capable of ensuring the above-mentioned.

[Constitution of device]

Therefore, in the present invention, a valve that opens when the upstream hydraulic pressure reaches a predetermined value and a valve that is arranged in parallel with this valve in the passage that reaches from the branch portion to the crankshaft system are connected to the crankshaft system. A bypass passage is provided to limit the flow rate of the lubricating oil supplied, and to open the valve when the temperature of the lubricating oil is low, or when the temperature of the lubricating oil is high and the oil pump is rotating at high speed. is doing.

That is, the bypass passage influences the operation of the valve in response to the temperature change of the lubricating oil, and the amount of the lubricating oil supplied to the crankshaft system is appropriately changed in cooperation with the valve, whereby the crankshaft system is The amount of lubricating oil supplied to the cylinder head system arranged at a higher position is controlled.

According to the present invention, when the temperature of the lubricating oil is low, or when the oil pump is in the high rotation state even when the temperature of the lubricating oil is high, the pressure on the upstream side of the valve increases and Is opened, and a sufficient amount of lubricating oil is supplied to the crankshaft system as well as an appropriate amount of lubricating oil to the cylinder head system.

On the other hand, when the temperature of the lubricating oil is high and the oil pump is in the low rotation state, the valve is not opened,
The supply amount of lubricating oil to the cylinder head system is secured by restricting the supply amount of lubricating oil to the crankshaft system.

〔Example〕

The present invention will be described below with reference to the embodiments shown in the drawings.

1 and 2 are conceptual diagrams showing the essential parts of a lubrication device for a four-cycle engine according to the present invention.

In this lubricating device, a branch portion 10 is provided in a main passage 11 extending from the oil pump 20, and the branch portion 1
0 through the main passage 11 through the crankshaft system 1
2 and a cylinder head system 13 arranged at a higher position than the crankshaft system 12. A valve 15 and a bypass passage 14 ′ arranged in parallel with the valve 15 are interposed in the passage 14 of the crankshaft system 12. The valve element 16 of the valve 15 is urged by the spring 17 to close the passage 14 in the unloaded state as shown in FIG. The relationship between the cross-sectional area and the length of the bypass passage 14 'and the urging force of the spring 17 are set so as to satisfy the operations described later. Reference numeral 19 in the drawing is a jet interposed in the passage 18 of the cylinder head system 13,
By limiting the flow rate of the lubricating oil supplied to the cylinder head system 13, it is possible to prevent problems such as mechanical loss in the valve mechanism and insufficient amount of stored lubricating oil in the oil pan.

The operation of the lubricating device will be described below, and the configuration will be described in more detail.

When the temperature of the lubricating oil is low, the resistance when passing through the main passage 11 and the passage 14 increases due to the influence of the viscosity of the lubricating oil. Therefore, regardless of the rotation state of the oil pump 20, the branch portion 10 is always provided with the cylinder. Sufficient hydraulic pressure is supplied to supply to the head system 13.

Therefore, in the above-mentioned state, as shown in FIG. 2, the valve body 16 of the valve 15 is moved rightward against the biasing force of the spring 17, and the oil pump 2
The lubricating oil pressure-fed from 0 to the branch portion 10 via the main passage 11 is supplied to the crankshaft system 12 via the valve 15 and the bypass passage 14 ', and is also supplied to the cylinder head system 13 via the jet 19 in an appropriate amount. The Rukoto.

On the other hand, when the temperature of the lubricating oil is high, the viscosity of the lubricating oil is reduced and the resistance when passing through the main passage 11 and the passage 14 is reduced. It is not possible to expect an increase in hydraulic pressure due to the effect of oil viscosity. Therefore, while the oil pump 20 is in the low rotation state and the discharge pressure and the discharge flow rate thereof are small, there is a fear that sufficient hydraulic pressure to be supplied to the cylinder head system 13 at the branch portion 10 may not be secured.

However, in the above-described state, as shown in FIG. 1, the valve body 16 of the valve 15 is kept closed by the urging force of the spring 17, and the lubricating oil supply path to the crankshaft system 12 is bypassed. Since the lubricating oil is restricted to the passage 14 'only,
The hydraulic pressure of the branch portion 10 is increased by the resistance when passing through, and the supply of the lubricating oil from the branch portion 10 to the cylinder head system 13 is secured.

Even when the temperature of the lubricating oil is high, the oil pump 20
In the high rotation state, the discharge pressure and the discharge flow rate of the oil pump 20 increase, so that the sufficient hydraulic pressure to supply the cylinder head system 13 at the branch portion 10 is secured.

Therefore, as in the case of the low oil temperature described above, the valve body 16 of the valve 15 is moved to the right against the biasing force of the spring 17, and the oil pump 20 moves from the main passage 1 to the main passage 1.
The lubricating oil pressure-fed to the branch portion 10 via
And through the bypass passage 14 ', the crankshaft system 1
2 is supplied to the cylinder head system 13 via the jet 19.

In the above embodiment, the bypass passage 14 'is connected to the valve 1
Although it is formed separately from 5, the valve of the present invention may of course incorporate a bypass passage.

[Effect of device]

As described above, according to the lubrication device for a four-cycle engine of the present invention, the valve is operated when the temperature of the lubricating oil is low or when the oil pump is in the high rotation state even when the temperature of the lubricating oil is high. Since the valve is closed when the temperature of the lubricating oil is high and the oil pump is in the low rotation state, the supply amount to the cylinder head system is increased when the temperature of the lubricating oil is low. In addition, it is possible to secure the supply amount to the cylinder head system when the temperature of the lubricating oil is high.

[Brief description of drawings]

1 and 2 conceptually show the essential parts of a lubrication device for a 4-cycle engine according to the present invention. FIG. 1 shows a closed state of a valve, and FIG. FIG. 3 is a diagram showing a valve open state, and FIG. 3 is a conceptual diagram showing a conventional four-cycle engine lubricating device. 10 ... Bifurcation part, 11 ... Main passage, 12 ... Crankshaft system, 13 ... Cylinder head system, 14 ... Passage, 14 '
... bypass passage, 15 ... valve, 16 ... valve body, 17 ... spring, 18 ... passage, 19 ... jet, 20 ... oil pump.

Claims (1)

[Scope of utility model registration request] 1. A branch is provided in a main passage extending from an oil pump, and lubricating oil is supplied from this branch to a crankshaft system, and a location higher than the crankshaft system is provided through a jet from the branch. In a four-cycle engine lubrication device adapted to supply lubricating oil to a cylinder head system arranged in the above, the oil pressure on the upstream side is interposed in a passage reaching from the branch portion to the crankshaft system. And a valve that opens in parallel with this valve to limit the flow rate of the lubricating oil supplied to the crankshaft system, and when the temperature of the lubricating oil is low and And a bypass passage for opening the valve when the oil pump rotates at a high speed. Jin of the lubricating device.