JP6809867B2 - Return oil confluence structure - Google Patents

Description

The present invention relates to a confluence structure of return oil.

Generally, lubricating oil used in an engine of an automobile or the like is circulated in the engine and used repeatedly, but when passing through the engine, it is a sliding portion between metals. Since the generated metal powder and sludge such as soot generated by combustion in the cylinder are mixed, such sludge is removed from the lubrication system by capturing it through an oil filter.

On the other hand, the blow-by gas leaking from the gap between the piston rings into the crankcase during the compression stroke and the explosion stroke of the engine fills the inside of the crankcase and the cylinder head cover communicating with the crankcase, and therefore from the inside of these. Although it is necessary to pull it out to the outside, the crankcase and connecting rod are moving at high speed inside the crankcase, and the rocker arm and valve are also operating inside the cylinder head cover that communicates with the crankcase, so the crankcase and cylinder The inside of the head cover is filled with oil mist.

Therefore, if the blow-by gas is released to the atmosphere as it is, the oil mist mixed with the blow-by gas may also be discharged to the outside. Therefore, a filter for separating and recovering the oil mist in the blow-by gas. A ventilator (CCV: Closed Crankcase Ventilator) with a built-in net or labyrinth structure is provided, and the blow-by gas extracted from the cylinder head cover of the engine is separated and recovered from the oil mist through the ventilator and then returned to the intake pipe (Patent Document). 1).

Then, as shown in FIG. 2, the oil 2 from which sludge has been removed by the oil filter 1 and the oil 4 separated and recovered from the blow-by gas by the ventilator 3 are merged and introduced into the oil cooler 5, and the oil cooler 5 is used. After being cooled, it is returned to the oil pan 6. At this time, the return pipe 7 that guides the oil 2 from the oil filter 1 and the drain pipe 8 that guides the oil 4 from the ventilator 3 are said. The single oil inlet 9 of the oil cooler 5 is fastened together by a joint bolt 10 and a union bolt 11 described later.

That is, as shown in detail in FIG. 3, the joint bolt 10 is screwed to the single oil inlet 9 formed in the cover 12 forming the inlet portion of the oil cooler 5 via the union bolt 11. The union bolt 11 and the joint bolt 10 are also screwed together in series, and the end of the drain pipe 8 of the ventilator 3 is fastened by the union bolt 11 and the oil filter 1 is fastened by the joint bolt 10. The end of the return pipe 7 is in a fastened state.

Here, the end of the drain pipe 8 is formed as a torus-shaped eye joint 8a, and the eye joint 8a is sandwiched between the head portion 11b and the cover 12 in a state where the eye joint 8a is fitted and mounted on the rod portion 11a of the union bolt 11. The end of the return pipe 7 is also formed as a torus-shaped eye joint 7a, and the head portion 10b is mounted on the rod portion 10a of the joint bolt 10 with the eye joint 7a fitted on the outside. The union bolt 11 is sandwiched between the union bolt 11 and the head portion 11b.

At this time, the inner peripheral side of each of the eye joints 7a and 8a is open, and the torus-shaped flow path 7b between the joint bolt 10 and the union bolt 11 rod portions 10a and 11a at the time of each fastening. 8b is defined, while the union bolt 11 is formed with a flow path 11c penetrating from the head portion 11b to the rod portion 11a over the entire length of the union bolt 11, and the flow path 11c provides a communication hole 11d. A flow path 10c is formed in the axial center of the rod portion 10a of the joint bolt 10 so as to communicate with the torus-shaped flow path 8b on the drain pipe 8 side, and the flow path 10c is a communication hole. It communicates with the torus-shaped flow path 7b on the return pipe 7 side via 10d.

Japanese Unexamined Patent Publication No. 2001-336413

However, in such a conventional structure, the return pipe 7 from the oil filter 1 and the drain pipe 8 from the ventilator 3 are connected to a single oil inlet 9 via a joint bolt 10 and a union bolt 11. Because they are connected together, the oils 2 and 4 of each system are merged in the middle of the narrow flow path 11c in the union bolt 11 and guided to the connecting flow path 13 of the oil cooler 5. The structure is such that the oil pressure at the confluence portion easily rises. In particular, in the head portion 11b of the union bolt 11, the oil 2 that has escaped from the narrow flow path 10c of the joint bolt 10 is once expanded and then again. Since the structure is such that the oil is narrowed down, when the flow rate of the oil 2 from the oil filter 1 increases more than a predetermined value depending on the operating conditions, the oil pressure at the confluence becomes higher than the oil pressure on the ventilator 3 side. There was a risk that the oils 2 and 4 would flow back toward the 3 side.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a return oil confluence structure capable of preventing backflow of oil to the ventilator side due to an increase in the flow rate of oil from the oil filter.

The present invention is a structure for merging the oil guided from the oil filter via the return pipe and the oil guided from the ventilator via the drain pipe and guiding the return pipe to a single connecting flow path. A first oil inlet for connecting and a second oil inlet for connecting the drain pipe are individually provided, and a bifurcated branch flow path is provided between the first and second oil inlets. It is characterized in that it is connected to the connecting flow path through the passage and the flow path cross-sectional area at the oil confluence from the first and second oil inlets is relatively expanded to form a plenum chamber for decompression. It is related to the structure of the confluence of the return oil.

Thus, in this way, the return pipe and the drain pipe are individually connected to the first and second oil inlets via joint bolts and the like, and the first and second oil inlets are connected. Since it is possible to join the oils introduced from each while securing the necessary and sufficient flow path cross-sectional area by the branch flow path, the conventional joint bolts are connected in series with the union bolts and the union bolts are narrow. It is not necessary to adopt a structure in which the oils of the respective systems are merged in the middle of the flow path, and even if the flow rate of the oil from the oil filter increases, the backflow of the oil to the ventilator side is less likely to occur.
Moreover, since the cross-sectional area of the flow path at the confluence of oils from the first and second oil inlets is relatively expanded to form a plenum chamber for decompression, the confluence of the branch flow paths is formed. Since the plenum chamber for decompression is formed, the increase in the oil pressure at the confluence is suppressed, and the backflow of oil to the ventilator side is more likely to occur.

Further, in carrying out the present invention more specifically, the section from the first oil introduction port to the inlet of the connecting flow path is linearly communicated and directed to the downstream side in the middle of the linear section. It is preferable to form a branch flow path so that the oil from the second oil inlet merges diagonally, and in this way, the oil is introduced from the return pipe to the first oil inlet by the Venturi effect and goes straight. The pressure on the drain pipe side decreases in proportion to the flow rate of the oil, and the backflow of the oil to the ventilator side becomes more difficult to occur.

According to the confluence structure of the return oil of the present invention described above, various excellent effects can be obtained as described below.

(I) According to the invention according to claim 1 of the present invention, the return pipe and the drain pipe can be individually connected to each of the first and second oil inlets via a joint bolt or the like. The oil introduced from each of the first and second oil inlets can be merged by the branch flow path while securing the necessary and sufficient flow path cross-sectional area , and moreover, for decompression at the junction of the branch flow paths. it is possible to prevent the Runode can suppress an increase in hydraulic pressure in the combined portion, back flow of oil to the ventilator side by the flow rate increase of the oil from the oil filter by the plenum chamber is formed.

(II) According to the invention according to claim 2 of the present invention, the pressure on the drain pipe side is reduced in proportion to the flow rate of the oil introduced from the return pipe to the first oil inlet and traveling straight by the Venturi effect. It is possible to further prevent the backflow of oil to the ventilator side.

It is sectional drawing which shows an example of the embodiment of this invention. It is an overall system diagram explaining a conventional example. It is sectional drawing which shows the detail of the main part of FIG. 2 in an enlarged manner.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an example of an embodiment of the present invention, which is guided from an oil filter 1 (see FIG. 2) via a return pipe 7 as in the case of the conventional structure described above with reference to FIGS. 2 and 3. The structure is such that the oil 2 and the oil 4 led from the ventilator 3 (see FIG. 2) via the drain pipe 8 are merged and led to a single connecting flow path 13 of the oil cooler 5. In the example, the oil introduction port 14 (first oil introduction port) for connecting the return pipe 7 and the oil introduction for connecting the drain pipe 8 to the cover 12 forming the inlet portion of the oil cooler 5 Ports 15 (second oil introduction ports) are individually provided, and the oil introduction ports 14 and 15 are connected to each other via a bifurcated branch flow path 16 to the communication flow path 13. ..

Here, both the end of the return pipe 7 and the end of the drain pipe 8 are formed as torus-shaped eye joints 7a and 8a as in the conventional structure, and the joint bolts 17 and 18 form the oil inlets 14 and 15. It is designed to be concluded for each. That is, each of the eye joints 7a and 8a is sandwiched between the head portions 17b and 18b by the head portions 17b and 18b in a state of being externally fitted to the rod portions 17a and 18a of the joint bolts 17 and 18.

Further, as already described in the explanation regarding the conventional structure, the inner peripheral side of each eye joint 7a, 8a is opened, and a torus shape is formed between the joint bolts 17 and 18 and the rod portions 17a, 18a at the time of fastening, respectively. The flow paths 7b and 8b are defined, and the flow paths 7b and 8b and the flow paths 17c and 18c at the axes of the rod portions 17a and 18a communicate with each other through the communication holes 17d and 18d. It is designed to do.

Further, particularly in this embodiment, the section from the oil introduction port 14 to the inlet of the connecting flow path 13 is linearly communicated, and the oil introduction port 15 is directed to the downstream side in the middle of the straight section. The branch flow path 16 is formed so that the oil 4 from the oil 4 merges diagonally, and the cross-sectional area of the flow path at the confluence of the oils 2 and 4 from the oil introduction ports 14 and 15 is relatively expanded. A plenum chamber 19 for depressurization is also formed.

Thus, in this way, the return pipe 7 and the drain pipe 8 are individually connected to the oil inlets 14 and 15 via the joint bolts 17 and 18, respectively, and from the oil inlets 14 and 15 respectively. Since the oils 2 and 4 to be introduced can be merged by the branch flow path 16 while securing the necessary and sufficient flow path cross-sectional area, the conventional joint bolt 10 (see FIG. 3) is replaced with the union bolt 11 (FIG. 3). It is not necessary to adopt a structure in which the oils 2 and 4 of the respective systems are merged in the narrow flow path 11c in the union bolt 11 (see FIG. 3) by connecting them in series (see 3), from the oil filter 1. Even if the flow rate of the oil 2 is increased, the backflow of the oils 2 and 4 to the ventilator 3 side is less likely to occur.

Further, particularly in this embodiment, the section from the oil introduction port 14 to the inlet of the connecting flow path 13 is linearly communicated, and the section from the oil introduction port 15 is directed to the downstream side in the middle of the linear section. Since the branch flow path 16 is formed so that the oil 4 merges diagonally, the drain pipe 8 side is proportional to the flow rate of the oil 2 introduced from the return pipe 7 to the oil introduction port 14 and traveling straight due to the Venturi effect. The pressure drops and the backflow of oils 2 and 4 to the ventilator 3 side is more unlikely to occur, but the formation of the plenum chamber 19 for decompression at the confluence of the branch flow path 16 also makes it more difficult for the oil at the confluence to flow back. The rise is suppressed, and the backflow of oils 2 and 4 to the ventilator 3 side is less likely to occur.

Therefore, according to the above embodiment, the return pipe 7 and the drain pipe 8 can be individually connected to the oil inlets 14 and 15 via the joint bolts 17 and 18, respectively, and the oil inlets 14 and 15 can be individually connected. Since the oils 2 and 4 introduced from each can be merged by the branch flow path 16 while securing the necessary and sufficient flow path cross-sectional area, the oil to the ventilator 3 side due to the increase in the flow rate of the oil 2 from the oil filter 1 It is possible to prevent a few backflows.

In particular, in the example of this embodiment, the pressure on the drain pipe 8 side can be reduced in proportion to the flow rate of the oil 2 introduced from the return pipe 7 to the oil inlet 14 and traveling straight by the venturi effect, and further, branching. Since the plenum chamber 19 for decompression is formed at the merging portion of the flow path 16, it is possible to suppress the increase in the oil pressure at the merging portion, so that the backflow of the oils 2 and 4 to the ventilator 3 side can be more reliably performed. Can be prevented.

The structure of the confluence of the return oil of the present invention is not limited to the above-mentioned embodiment, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

1 Oil filter 2 Oil 3 Ventilator 4 Oil 7 Return pipe 8 Drain pipe 13 Communication flow path 14 Oil inlet (first oil inlet)
15 Oil inlet (second oil inlet)
16 Branch flow path 19 Plenum chamber

Claims (2)

It is a structure for merging the oil guided from the oil filter via the return pipe and the oil guided from the ventilator via the drain pipe and guiding them to a single connecting flow path, and for connecting the return pipes. A first oil inlet and a second oil inlet for connecting a drain pipe are individually provided, and the first and second oil inlets are communicated with each other via a bifurcated branch flow path. A return oil that is connected to the flow path and has a plenum chamber for decompression formed by relatively expanding the flow path cross-sectional area at the confluence of oils from the first and second oil inlets . Confluence structure. The section from the first oil inlet to the inlet of the connecting flow path is linearly communicated, and the oil from the second oil inlet merges diagonally toward the downstream side in the middle of the linear section. The return oil confluence structure according to claim 1, wherein the branch flow path is formed as described above.

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