JP2542110Y2 - Lubricating oil circuit of internal combustion engine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating oil circuit for an internal combustion engine, and more particularly to a lubricating oil circuit for an engine such as a construction machine.

[0002]

2. Description of the Related Art FIG. 4 is a system diagram of a lubricating oil circuit of an engine of a conventional construction machine. An oil pan 1 of the engine is composed of a deep oil reservoir 2 and a shallow oil receiver 3 due to the structure of the vehicle body. . The main oil pump 4 sucks up the lubricating oil from the oil reservoir 2 through the oil strainer 5, sends the lubricating oil to the lubrication unit 7 through the full flow oil filter 6, performs necessary lubrication, and returns the oil to the oil reservoir 2. In recent years, the time interval between cleaning or replacement of the full flow oil filter 6 due to dirt has been extended, and a bypass oil filter has been used. That is, a bypass circuit 17 is provided in a circuit from the main oil pump 4 to the full flow oil filter 6, and a part of the lubricating oil is returned to the oil reservoir 2 through the bypass oil filter 13. Therefore, dirt of the lubricating oil and clogging of the oil filter are reduced, and the time interval between cleaning and replacement can be extended.

When the vehicle body is tilted due to work on a slope or the like, as shown in FIG. 5, the lubricating oil moves from the oil reservoir 2 to the oil receiver 3, and the oil strainer 5 of the main oil pump 4 comes out into the air, and May not be sucked in and may burn the engine. Therefore, an oil scavenging pump 10 is provided to transfer the lubricating oil moved to the oil receiver 3 to the oil strainer 11.
And is returned to the oil sump 2 by the scavenging circuit 14.

[0004]

However, according to the above configuration, the main oil pump flows the lubricating oil to both the full flow oil filter and the bypass oil filter, so that the discharge amount is larger than that required for lubrication. There is a need. In addition, the oil scavenging pump is always driven, even though it is unnecessary on a flat ground or a slightly sloping ground, and is uneconomical.

The present invention has been made in view of the above-mentioned problems. An economical lubricating oil circuit for an internal combustion engine, in which the discharge amount of the main oil pump is small and the oil scavenging pump operates efficiently. It is intended to provide.

[0006]

In order to achieve the above object,
In a first invention of a lubricating oil circuit for an internal combustion engine according to the present invention, in a lubricating oil circuit for an internal combustion engine including a main oil pump, a full flow oil filter, a bypass oil filter, and an oil scavenging pump, A circuit from the main oil pump to the lubrication section via the full flow oil filter, and a circuit from the oil scavenging pump to the bypass oil filter and the scavenging circuit via a directional switching valve. In the second invention, an inclination angle detector that detects an inclination angle of a vehicle and issues a signal when a predetermined angle is reached, and receives a signal from the inclination angle detector and sends the signal to the direction switching valve. And a control device that emits a signal to perform control.

[0007]

According to the above construction, the main oil pump has independent circuits for the full flow filter and the lubricating section, and pumps the lubricating oil to a necessary portion. A directional control valve is provided between the oil scavenging pump and the bypass oil filter and the scavenging circuit, and a control device for controlling the directional control valve by a signal from the vehicle body inclination angle detecting device is provided. The pump sends the lubricating oil to the bypass oil filter, and when the inclination angle of the vehicle body reaches a predetermined angle, switches the direction switching valve to send the lubricating oil from the oil receiver to the oil reservoir.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a lubricating oil circuit for an internal combustion engine according to the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram of a lubricating oil circuit according to the present invention.
From an oil reservoir 2 of an oil pan 1 having a main oil pump 4
Sucks up the lubricating oil through the oil strainer 5 and sends it to the lubricating unit 7 through the full flow filter 6. The discharge amount of the main oil pump 4 is an amount necessary for lubrication. The oil scavenging pump 10 sucks up lubricating oil from the oil receiver 3 via an oil strainer 11, and connects to a bypass oil filter 13 and a scavenging circuit 14 via an electromagnetic directional switching valve 12 having a and b2 positions. I have.
The tilt angle detector 15 mounted on the vehicle body is connected to a control device 16 that receives a signal from the tilt angle detector 15 and controls the direction switching valve 12.

Next, the operation of the oil scavenging pump will be described. Normally, the direction switching valve 12 is at the position a, and the lubricating oil is sent from the oil scavenging pump 10 to the bypass oil filter 13 and returned to the oil pan 1. As construction work is often performed on uneven terrain,
As shown in (1), the lubricating oil in the oil pan swings and the lubricating oil in the oil reservoir 2 often moves to the oil receiver 3. Therefore, a considerable amount of lubricating oil is filtered through the bypass filter 13,
This contributes to extending the replacement time interval of the full flow filter 6. When the vehicle body leans, such as when working on a slope, when the vehicle reaches a predetermined angle α as shown in FIG. 3, the tilt angle detector 15 sends a signal to the control device 16, and the control device 16 receiving the signal sends the signal to the control device 16. The direction switching valve 12 is switched from the position a to the position b, and the lubricating oil moved to the oil receiver 3 is returned to the oil sump 2 by the scavenging circuit 14 to prevent seizure of the engine.

[0010]

[Effects of the Invention] As described above, in the present invention, the circuit of the main oil pump is only a circuit leading to the lubrication section through the full flow oil filter, so that the discharge amount required for lubrication is sufficient, and the pump can be downsized. . Also, a direction switching valve is provided on the discharge side of the oil scavenging pump so that the lubricating oil is always sent to the bypass oil filter, and the lubricating oil in the oil receiver is sent to the oil sump when the vehicle body reaches a predetermined inclination angle. As a result, the oil scavenging pump can always perform effective work, extend the oil filter replacement time interval, and obtain an economical lubricating oil circuit for internal combustion engines that does not burn the engine even when working on slopes. Can be

[Brief description of the drawings]

FIG. 1 is a system diagram of a lubricating oil circuit of the present invention.

FIG. 2 is a system diagram showing a state of the lubricating oil circuit according to the present invention during operation.

FIG. 3 is a system diagram showing a state of the lubricating oil circuit of the present invention on a slope.

FIG. 4 is a system diagram of a conventional lubricating oil circuit.

FIG. 5 is a system diagram showing a state of a conventional lubricating oil circuit on a slope.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 oil pan 2 oil reservoir 3 oil receiver 4 main oil pump 6 full flow oil filter 7 lubrication unit 10 oil scavenging pump 12 directional switching valve 13 bypass oil filter 14 scavenging circuit 15 inclination angle detector 16 controller

Claims (2)

(57) [Scope of request for utility model registration] In a lubricating oil circuit of an internal combustion engine including a main oil pump, a full flow oil filter, a bypass oil filter, and an oil scavenging pump, a lubricating portion is provided from the main oil pump through the full flow oil filter. A lubricating oil circuit for an internal combustion engine, comprising: a circuit from the oil scavenging pump to the bypass oil filter and a scavenging circuit via a directional switching valve. 2. A tilt angle detector which detects a tilt angle of a vehicle and issues a signal when a predetermined angle is reached, and receives a signal from the tilt angle detector and issues a signal to the direction switching valve. The lubricating oil circuit for an internal combustion engine according to claim 1, further comprising a control device for controlling.