JPH1054216A - Engine lubrication device - Google Patents

Abstract

(57) [Summary] In an engine lubrication device, a bypass filter can be protected from high-pressure lubricating oil when the engine is started. An oil pump has a suction side connected to an oil pan and a discharge side connected to a supply passage.
Then, the oil pump 2 supplies the lubricating oil to the lubrication target portion 6 of the engine body via the supply passage 4. In addition, a relief valve 5 is provided between the oil pump 2 and the supply passage 4. Furthermore, the inflow side 1 of the bypass pipe 11
1A is connected to the inflow side 4A of the supply passage 4, and the outflow side 11B
To the oil pan 1 side. In addition, the bypass line 11
Is provided with a shut valve 17 located upstream of the bypass filter 8. When the pressure of the lubricating oil discharged from the oil pump 2 exceeds a predetermined value, the shut-off valve 17 is closed, and the lubricating oil flowing through the bypass pipe 11 toward the bypass filter 8 is shut off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating apparatus for an engine suitable for use in an engine such as a construction machine for supplying lubricating oil in an oil pan to a portion to be lubricated such as a cylinder or a bearing. .

[0002]

2. Description of the Related Art A conventional lubricating device for an engine will be described with reference to FIG.

[0003] In the drawings, reference numeral 1 denotes an oil pan provided on the bottom side of a crankcase of an engine body.
A lubricating oil for lubricating a lubrication target portion 6 of the engine body described later is stored in the inside.

[0004] Reference numeral 2 denotes an oil pump provided in the engine main body. The oil pump 2 has a suction side 2A opened in the oil pan 1 and a discharge side 2B connected to a supply passage 4 described later. Then, the oil pump 2 discharges and supplies the lubricating oil in the oil pan 1 sucked from the suction side 2A toward the lubrication target portion 6 through the supply passage 4.

Reference numeral 3 denotes a wire mesh oil strainer attached to the suction side 2A of the oil pump 2. The oil strainer 3 filters relatively large foreign matters mixed in the lubricating oil.
The foreign matter is prevented from damaging the oil pump 2 and the like.

Reference numeral 4 denotes a supply passage provided in the engine main body. The supply passage 4 has an inflow side 4A connected to the discharge side 2B of the oil pump 2 and is directed toward each part of the engine main body to be a lubrication target portion 6. Extending. The inflow side 4A of the supply passage 4 is formed inside the engine body at a position near the outer wall of the engine body. On the other hand, a full-flow filter for filtering the lubricating oil supplied to the lubrication target portion 6 and a supply amount of the lubricating oil which communicates before and after the clogging of the full-flow filter are provided on the inflow side 4A of the supply passage 4. A bypass valve (neither is shown) or the like for ensuring the above is provided.

[0007] Reference numeral 5 denotes a relief valve provided between the discharge side 2B of the oil pump 2 and the inflow side 4A of the supply passage 4. The relief valve 5 is discharged from the oil pump 2 toward the supply passage 4. When the lubricating oil exceeds a predetermined relief pressure PR (for example, about 20 kg / cm ² ), the lubricating oil is relieved toward the oil pan 1 via the relief pipe 5A.

Reference numeral 6 denotes a portion to be lubricated of the engine main body which requires supply of lubricating oil. The portion to be lubricated 6 is, for example, a sliding surface of a cylinder with respect to a piston, or a bearing portion such as a crankshaft, a camshaft, a connecting rod, and the like. Includes movable parts such as a rocker arm and a turbocharger.

Reference numeral 7 denotes a bypass line for returning a part of the lubricating oil discharged from the oil pump 2 to the oil pan 1 side. The bypass line 7 has an inflow side 7A on the inflow side 4A of the supply passage 4.
And the outflow side 7B is connected to the oil pan 1 side.

Reference numeral 8 denotes a bypass filter provided in the middle of the bypass line 7. The bypass filter 8 filters the lubricating oil flowing in the bypass line 7, and removes fine wear powder and lubricating oil mixed in the lubricating oil. Oil oxides (sludge) and the like are removed. The bypass filter 8 has a predetermined withstand voltage value PB (for example, 15 kg / cm).
^{About 2} ).

Reference numeral 9 denotes a driving source for driving the oil pump 2 during operation of the engine. The driving source 9 may be constituted by an engine body, or may be constituted by an electric motor attached to the engine body. .

The lubricating device for an engine according to the prior art has the above-described configuration, and its operation will be described below.

First, when the oil pump 2 is driven by the drive source 9, the lubricating oil in the oil pan 1 is removed from the oil pump 2 via the supply passage 4 after relatively large dust and the like are removed by the oil strainer 3. Is supplied to the lubrication target portion 6. Then, the lubricating oil that has lubricated the lubrication target portion 6 is returned to the oil pan 1 via the inside of the crankcase or the like.

On the other hand, a part (for example, about 20%) of the lubricating oil discharged from the oil pump 2 flows into the bypass pipe 7 from the inflow side 4A of the supply passage 4, and the fine abrasion powder is formed by the bypass filter 8. After the sludge and the like are removed, it is returned to the oil pan 1 side.

[0015]

In the prior art described above, for example, when the oil having a high viscosity is discharged from the oil pump 2 at the time of starting the engine or the like, an excessive pressure may be generated. The valve 5 relieves the excess pressure toward the oil pan 1 to protect a lubrication system such as the oil pump 2 and the supply passage 4.

However, the relief pressure P of the relief valve 5
When R is set to a low pressure, the pressure of the lubricating oil discharged from the oil pump 2 decreases, and the lubricating oil cannot always be sufficiently supplied to the lubrication target portion 6 of the engine body. Therefore, in the prior art, the relief pressure PR of the relief valve 5 is set to a pressure value of about 20 kg / cm ² .

On the other hand, the bypass filter 8 is used to efficiently remove fine wear powder, sludge and the like in the lubricating oil.
Since the bypass filter 8 is formed of a filter having a fine mesh diameter, the withstand voltage value PB of the bypass filter 8 is, for example, 15 k
g / cm ² .

For this reason, in the prior art, the relief pressure PR of the relief valve 5 is less than the withstand pressure value PB of the bypass filter 8.
When the pressure of the lubricating oil rises to a pressure close to the relief pressure PR of the relief valve 5 by setting the pressure higher than the pressure, the pressure exceeding the pressure resistance value PB acts on the bypass filter 8, and the bypass filter 8 There is a problem that is damaged.

On the other hand, by setting the relief pressure PR of the relief valve 5 to a pressure lower than the pressure resistance value PB of the bypass filter 8 or by providing a throttle in the middle of the bypass line 7, the pressure of the lubricating oil can be reduced. May be lower than the withstand voltage value PB of the bypass filter 8.

However, when the engine is started in a cold region, for example, a surge pressure greater than the relief pressure PR of the leaf valve 5 is likely to be generated because the high-viscosity lubricating oil is discharged from the oil pump 2. . When such a surge pressure is generated in the bypass pipe 7 or the like, a pressure exceeding the withstand voltage value PB is instantaneously applied to the bypass filter 8, and there is a problem that the bypass filter 8 is damaged early.

The present invention has been made in view of the above-mentioned problems of the prior art, and the present invention ensures that the bypass filter is not damaged even when the pressure of the lubricating oil discharged from the oil pump becomes high. It is an object of the present invention to provide an engine lubricating device that can prevent such problems and improve the durability and reliability of a bypass filter.

[0022]

According to the present invention, there is provided an oil pan provided in an engine body for storing lubricating oil, and lubricating oil in the oil pan is lubricated by the engine body. An oil pump that discharges and supplies a portion of the lubricating oil discharged from the oil pump, a bypass pipe that returns a part of the lubricating oil discharged from the oil pump to the oil pan side, and a bypass pipe that is provided in the middle of the bypass pipe. The present invention is applied to a lubricating device for an engine including a bypass filter for filtering flowing lubricating oil.

A feature of the structure adopted by the first aspect of the present invention is that the bypass pipe is located at a position upstream of the bypass filter and is always open, and is discharged from the oil pump. Valve means for closing when the pressure of the lubricating oil exceeds a predetermined set value, wherein the valve means prevents the lubricating oil from flowing toward the bypass filter when the valve is closed. I did it.

According to the above configuration, the valve means is closed at a pressure lower than the withstand pressure value of the bypass filter.
The valve means can be closed before the pressure of the lubricating oil discharged from the oil pump exceeds the pressure resistance value of the bypass filter, and high-pressure lubricating oil can be prevented from flowing toward the bypass filter.

According to the second aspect of the present invention, the valve means forms a part of the bypass pipe with a mounting bolt for mounting an end of the bypass pipe to an engine body. A lubricating oil passage formed in the mounting bolt, a valve body located in the lubricating oil passage and movably provided in the mounting bolt, and a valve body that is constantly urged in a valve opening direction. And a spring provided in the mounting bolt to allow the valve body to close when the pressure of the lubricating oil discharged from the oil pump exceeds the set value.

Thus, the valve means can be constituted by mounting bolts for mounting the end side of the bypass pipe to the engine body or the like.
By the valve means (mounting bolt), the end side of the bypass pipe can be connected to the engine body side (discharge side of the oil pump). When the pressure of the lubricating oil discharged from the oil pump exceeds the set value, the valve element in the mounting bolt is closed against the spring, and the lubricating oil passage in the mounting bolt is shut off by the valve element. it can.

[0027]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIGS. 1 to 4 show an embodiment of the present invention. In this embodiment, the same components as those of the prior art are denoted by the same reference numerals, and the description thereof will be omitted.

In the figure, reference numeral 11 denotes a bypass line formed in the same manner as in the prior art.
A is connected to the inflow side 4A of the supply passage 4 and the outflow side 11B
Are connected to the oil pan 1 side. However, in the present embodiment, the bypass pipe 11 is connected to the pipes 12 and 13, the mounting bolt 15 and the lubricating oil passage 2 of the shut valve 17, which will be described later.
1 and so on.

Numerals 12 and 13 are pipes constituting a part of the bypass pipe 11, and joints 14, 14,... Described later are attached to both ends of the pipes 12, 13 as shown in FIG.
As shown in FIG. 4, an end 12 </ b> A of the pipe 12 is fastened to a wall 16 of the engine body by a mounting bolt 18 (shut valve 17), which will be described later, inserted into the joint 14.

The end 13A of the pipe 13 is connected to the oil pan 1 via a mounting bolt 15 inserted into the joint 14, and the ends 12B, 13 of the pipes 12, 13 are connected.
B is similarly connected to the bypass filter 8 via each mounting bolt 15.

Are joints attached to both end portions of the pipes 12, 13, and the joints 14 are, as shown in FIG.
7 has an insertion hole 14A through which the hole 7 is inserted, and an annular recess 14B formed around the insertion hole 14A.
The inside is communicated with the pipes 12 and 13.

Are mounting bolts for the pipes 12, 13, each of which is formed in a bottomed cylindrical shape with an open end at the tip end as shown in FIG. 15A. A radial passage 15 </ b> B is formed on the base end side surface of the mounting bolt 15. These mounting bolts 15 are actually used in the prior art.

Reference numeral 16 denotes a wall of the engine body to which the end 12A of the pipe 12 is fastened. The wall 16 is located in the engine body as shown in FIG.
Are formed. In addition, a screw hole 16 </ b> A communicating with the inflow side 4 </ b> A of the supply passage 4 is formed in the wall portion 16.

When the shut-off valve 17 is opened, a part of the lubricating oil discharged from the oil pump 2 flows from the inflow side 4A of the supply passage 4 in the direction of arrow A in FIG.
2 and flows through the pipe 12 in the direction of arrow B. Further, the lubricating oil is supplied to the bypass filter 8.
After flowing through the inside of the pipe 13 in the direction of arrow C through the inside, the pipe 13 is returned from the end 13A of the pipe 13 to the oil pan 1 side of the engine.

Reference numeral 17 denotes a shut-off valve as valve means according to the present embodiment. As shown in FIGS. 1 and 2, the shut-off valve 17 is located on the upstream side (inflow side) of the bypass filter 8 and has a bypass pipe. As shown in FIG. 4, the mounting bolt 18 and the lubricating oil passage 2
1, a ball valve body 22 and a spring 23. The shut valve 17 is inserted into an insertion hole 14A of a joint 14 attached to an end 12A of the pipe 12, and is screwed into a screw hole 16A of a wall 16 of the engine body.

Reference numeral 18 denotes a mounting bolt forming a valve casing of the shut-off valve 17. The mounting bolt 18 is formed in a bottomed cylindrical shape having an open end at the distal end, and has a small-diameter hole 18A at the proximal end inside the mounting bolt. And the large-diameter hole 1 on the tip (opening end) side
8B. Further, radial passages 18C, 18C are formed on the side surface of the mounting bolt 18 so as to communicate with the small-diameter hole 18A.

Further, the small-diameter hole 18A and the large-diameter hole 18B
An annular enlarged diameter portion that expands in a tapered shape is formed between the two, and this enlarged diameter portion serves as a valve seat 19 on which the ball valve body 22 separates and sits. The mounting bolt 18 is formed, for example, with two caulking portions 20, 20 located on the opening end side of the large-diameter hole portion 18 </ b> B so as to face each other in the diametrical direction.
Holds the ball valve body 22 in the large-diameter hole portion 18B in a retaining state. The mounting bolt 18 can be manufactured, for example, by drilling the mounting bolt 15 from the opening end side of the shaft hole 15A to form a large-diameter hole 18B.

Numeral 21 denotes a lubricating oil passage formed in the mounting bolt 18. The lubricating oil passage 21 has a small-diameter hole portion 18 A, a large-diameter hole portion 18 B and a radial passage 18 C of the mounting bolt 18.
And constitutes a part of the bypass pipeline 11.

Numeral 22 designates a ball valve as a valve movably disposed in the mounting bolt 18 in the middle of the lubricating oil passage 21, and the ball valve 22 has an outer diameter of the mounting bolt 18. The diameter of the large-diameter hole 1 is larger than the inner diameter of the small-diameter hole 18A.
It is formed so as to have a smaller diameter than the inner diameter of 8B.

When the shut-off valve 17 is opened, the pipe 12 of the bypass pipe 11 and the inflow side 4 A of the supply passage 4 are communicated via the lubricating oil passage 21. When the shut valve 17 is closed, the ball valve body 22 is
9, the lubricating oil passage 21 is shut off halfway, and the lubricating oil in the supply passage 4 is connected to the pipe 1 toward the bypass filter 8.
2 is blocked.

Reference numeral 23 denotes a spring which constantly urges the ball valve body 22 in the valve opening direction. The spring 23 is disposed in the small-diameter hole 18A of the mounting bolt 18 so as to set the shut valve 17 to a set value. The pressure PS is determined.
When the pressure of the lubricating oil flowing into the large-diameter hole portion 18B of the mounting bolt 18 exceeds the valve closing pressure PS, the spring 23 closes the ball valve body 22 by sitting on the valve seat 19. It is configured to allow.

Here, the valve closing pressure PS is equal to the relief valve 5
Pressure PR and withstand pressure value P of bypass filter 8
This is a preset value that is smaller than B (PR>PB> PS), and is set to a pressure value of, for example, about 12 kg / cm ² .

Are packings for sealing the lubricating oil, and each packing 24 is mounted between the mounting bolt 15 or the shut valve 17 and the wall 16 side with a tight allowance.

The engine lubricating apparatus according to this embodiment has the above-described configuration, and its operation will be described below.

First, the lubricating oil discharged from the oil pump 2 is supplied from the oil pump 2 to the supply passage 4 as in the prior art.
Is supplied to the lubrication target portion 6 through the lubrication oil, and a part of the pressure is supplied to the relief pressure PR of the relief valve 5 by the pressure of the lubricating oil.
When the pressure is smaller than the valve closing pressure PS of the shut valve 17, the oil flows into the bypass pipe 11 through the lubricating oil passage 21 in the shut valve 17 and returns to the oil pan 1 through the bypass pipe 11. It is.

That is, as shown in FIG. 4, a part of the lubricating oil flows from the supply passage 4 (inflow side 4A) in the wall 16 of the engine body to the lubricating oil passage 21 in the shut valve 17 in the direction of arrow A as shown in FIG. The gas flows into the pipe 12 via the lubricating oil passage 21 and the like, and flows in the direction indicated by the arrow B in FIG.

On the other hand, when the pressure of the lubricating oil discharged from the oil pump 2 rises and exceeds the valve closing pressure PS of the shut valve 17, the ball valve body 22 shown in FIG. It is pushed in the direction of arrow A against 23 and seated on the valve seat 19. As a result, the lubricating oil passage 21 is shut off, the shut valve 17 is closed, and the lubricating oil is prevented from flowing into the bypass pipe 11.

Thus, in this embodiment, since the shutoff valve 17 is provided in the bypass pipe line 11 at the upstream side (inflow side) of the bypass filter 8, the pressure of the lubricating oil discharged from the oil pump 2 is increased. Is shut valve 1
7, the shut-off valve 17 is exceeded.
Is closed, the lubricating oil can be reliably prevented from flowing into the bypass filter 8 side.

Therefore, according to the present embodiment, even when the pressure of the lubricating oil discharged from the oil pump 2 rises, for example, when the engine is started, and becomes higher than the pressure resistance value PB of the bypass filter 8, Damage to the bypass filter 8 by this lubricating oil can be reliably prevented, and the durability and reliability of the bypass filter 8 can be greatly improved.

Further, the shut valve 17 is attached to the mounting bolt 1.
8, the valve means provided in the bypass pipe 11 can be reduced in size, and the shut valve 17 can be easily mounted without newly providing a space for the shut valve 17 in the bypass pipe 11. .

Further, by providing the shut-off valve 17, the valve closing pressure PS can be appropriately set according to the withstand pressure value PB of the bypass filter 8, and the like. Therefore, the relief pressure PR of the relief valve 5 can be set according to other design requirements. It can be set freely according to the conditions.

Further, since the shut-off valve 17 is provided in the bypass line 11 and the return of the lubricating oil through the bypass line 11 is shut off only when the pressure of the lubricating oil is high, the lubrication target portion 6 Without interrupting the flow of the lubricating oil supplied to the filter and stopping the filtering of the lubricating oil by the bypass filter 8 for a long time.
Can be reliably protected.

On the other hand, a shut valve 17 is provided with a mounting bolt 18 formed from the same mounting bolt 15 as the prior art,
Since the configuration includes the ball valve element 22 and the spring 23, the shut valve 17 can be manufactured by a simple processing operation, and the mounting bolt 15 attached to the end 12A of the pipe 12 in the related art is replaced with the shut valve 17. By doing so, the bypass filter 8 can be easily protected.

That is, when the shut valve 17 is formed,
The spring 23 and the ball valve body 22 are inserted into the mounting bolts 18 formed by, for example, drilling the mounting bolts 15, and then a part of the opening end side of the mounting bolts 18 is connected to the lubricating oil passage. By swaging inward into each other and forming each caulking portion 20, the shut valve 17 is formed.
Can be easily formed.

In the above embodiment, the shut valve 1
Although the pipe 12 is fastened to the wall 16 of the engine body by the mounting bolts 7 (the mounting bolts 18), the present invention is not limited to this, and the valve is closed when the pressure of the lubricating oil exceeds a predetermined set value. The shut valve may be provided in the bypass line 11 in the engine body, for example.

In the above embodiment, the lubricating device for an engine mounted on a construction machine has been described as an example. However, the present invention is not limited to this. The present invention can be applied, for example, to an engine of an automobile, an engine of an industrial machine, an agricultural machine, or the like.

[0058]

As described above in detail, according to the first aspect of the present invention, since the valve means is provided on the bypass pipe located upstream of the bypass filter, the oil is discharged from the oil pump. When the pressure of the lubricating oil exceeds a predetermined set value, the lubricating oil can be reliably prevented from flowing into the bypass filter by the valve means. Therefore, even when the pressure of the lubricating oil discharged from the oil pump becomes high, for example, at the time of starting the engine, it is possible to reliably prevent the bypass filter from being damaged, thereby improving the durability and reliability of the bypass filter. Can be greatly improved.

According to the second aspect of the present invention, the valve is formed by the mounting bolt for mounting the end of the bypass pipe to the engine body, the lubricating oil passage in the mounting bolt, the valve element and the spring. Since the means is configured, the size of the valve means can be reduced, and the valve means can be easily attached to the bypass pipe. Further, the valve means can be easily formed from the mounting bolts of the current product, and the bypass filter can be easily protected only by replacing the mounting bolts of the current product with the valve means.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an engine lubrication device according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a bypass pipe, a shut valve, a mounting bolt, a bypass filter, and the like.

FIG. 3 is a longitudinal sectional view showing a mounting bolt in FIG. 2;

4 is a longitudinal sectional view showing a state in which a pipe is fastened to an engine body side by a shut valve in FIG. 2;

FIG. 1 shows a conventional engine lubrication apparatus.
It is a circuit diagram similar to.

[Explanation of symbols]

 Reference Signs List 1 oil pan 2 oil pump 6 lubrication target part 8 bypass filter 11 bypass pipe 16 wall of engine body 17 shut valve (valve means) 18 mounting bolt 21 lubricating oil passage 22 ball valve element (valve element) 23 spring PS closing valve Pressure (set value)

Claims (2)

[Claims] 1. An oil pan provided in an engine main body for storing lubricating oil, an oil pump for discharging lubricating oil in the oil pan toward a lubrication target portion of the engine main body, and discharging from the oil pump. Engine lubrication comprising: a bypass pipe for returning a part of the lubricating oil returned to the oil pan side; and a bypass filter provided in the middle of the bypass pipe for filtering the lubricating oil flowing in the bypass pipe. In the device, the bypass pipe is located at an upstream side of the bypass filter and is always open, and when the pressure of the lubricating oil discharged from the oil pump exceeds a predetermined set value. A lubricating device for an engine, comprising: valve means for closing a valve, wherein the valve means is configured to prevent the flow of lubricating oil toward the bypass filter when the valve is closed. 2. The valve means according to claim 1, wherein said valve means includes a mounting bolt for mounting an end portion of said bypass pipe to an engine body side, and a lubrication formed in said mounting bolt so as to form a part of said bypass pipe. An oil passage, a valve body located in the middle of the lubricating oil passage and movably provided in the mounting bolt, and provided in the mounting bolt so as to constantly bias the valve body in a valve opening direction; 2. The engine lubricating device according to claim 1, further comprising a spring that allows the valve body to close when the pressure of the lubricating oil discharged from the oil pump exceeds the set value.