JPH0454804Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

The present invention relates to the structure of an oil strainer that is attached to the lower end opening of an oil pipe connected to an engine oil pump.
This invention relates to a structure for reducing oil pan noise caused by pressure fluctuations within an oil pipe.

[Conventional technology]

Generally, in order to draw oil stored in an oil pan into an oil pump of an engine, an oil pipe is provided, the upper end of which is connected to the intake port of the oil pump, and the lower end of which is inserted into the oil.
An oil strainer is provided on the periphery of the lower end opening of the oil pipe, and includes an air entrainment prevention member that extends in the radial direction of the oil pipe, and a mesh that is integrally assembled with the air entrainment prevention member. 7 and 8 are vertical cross-sectional views showing the structure of the conventional oil strainer, FIG. 7 is a vertical cross-sectional view showing the main parts of the oil strainer, and FIG. 8 is a view showing how it is assembled into an engine. FIG. As shown in FIG. 7, the oil strainer 1
A flat plate 3 as a member for preventing air from entering the oil pipe 2 is integrally assembled by welding or other methods around the periphery of the lower end opening of the oil pipe 2 and extends in the radial direction. A net 4 is attached to prevent this. The net 4 is fixed to the flat plate 3 by annular clip members, rivets, caulking, etc. (not shown). As shown in FIG. 8, the upper end of the oil pipe 2 constituting the oil strainer 1 is connected to the suction port 14 formed in the cylinder block 12. The oil in 11 is the oil pump 13
It is pumped to. The oil pumped up by the oil pump 13 is supplied to the sliding parts of various parts of the engine via the discharge port 15. Figures 9 and 10 show the oil pump 1 described above.
FIG. 3 is an explanatory diagram schematically showing the operation of No. 3; The oil pump 13 is generally of a trochoid type, an external gear type, an internal gear type, etc., but to explain a trochoid type oil pump as an example, an outer rotor 13a and an inner rotor 1 inserted into an oil pump housing (not shown) are used.
3b. A shaft and a pulley (not shown) are attached to the inner rotor 13b, and the inner rotor 13b is rotated in the direction of arrow A in the figure by a timing belt wound around the pulley. Following this rotation of the inner rotor 13b, the outer rotor 13a is also rotated in the direction of arrow A, and the space formed between the outer rotor 13a and the inner rotor 13b is communicated with the suction port 14, so that the oil in the oil pan 11 is The oil is pumped up and communicated with the discharge port 15 to pressurize the oil and supply it to each part of the engine. When such an oil pump 13 is used to supply lubricating oil to various parts of the engine, pressure fluctuations (shock waves) occur within the oil pipe as the oil pump 13 rotates, causing the film on the bottom wall 11a of the oil pan 11 to Vibration may occur. To explain this phenomenon using FIGS. 9 and 10, as shown in FIG. 9, the oil pump 1
From the discharge stroke to the suction stroke of No. 3, a part of the oil that should be supplied to each part of the engine from the discharge port 15 remains in the space 16, and this space 1
6 is contracted as the inner rotor 13b and outer rotor 13a rotate. When the volume of the contracted space 16 is rapidly expanded during the suction stroke, the inside of the space 16 becomes temporarily in a vacuum state. Therefore, so-called cavitation occurs in which the gas in the oil remaining in the space 16 separates and bubbles are generated. That is, when the space 16 and the suction port 14 are brought into communication from a vacuum state in which the bubbles are separated and expanded, the bubbles are rapidly crushed by the atmospheric pressure, and an abnormally high pressure is generated locally. When pressure fluctuation occurs due to this cavitation, the shock wave propagates through the oil pipe 2 and acts as an excitation force on the bottom wall 11a of the oil pan 11, inducing membrane vibration of the oil pan 11. Further, as shown in FIG. 10, the outer rotor 13a, the inner rotor 13b, or the suction port 1
4. Depending on the shape of the discharge port 15, a space 21 is created in which oil sucked from the suction port 14 is stored and pressurized.
Before the communication with the suction port 14 is cut off, the discharge port 1
5, and the high-pressure oil pressurized in the space 22 may flow back to the suction port 14 through this space 21. If the oil flows back into the oil pan 11 from the oil pump 13 through the suction port 14 in this way, high-pressure oil will impact the oil pan 11 as shown by arrow B in FIG.
1, the bottom wall 11a causes membrane vibration and noise is generated. As a means of suppressing such noise from the oil pan 11, a barrier member having a shape opposite to the axis of the oil pipe is conventionally provided at the lower end opening of the oil pipe, so that the oil that flows back flows directly to the bottom wall 11a of the oil pan 11. A configuration that prevents collision has been proposed (for example, Japanese Utility Model Application Publication No. 57-003811). FIG. 11 is a longitudinal sectional view showing the main part of a conventional device provided with the above-mentioned barrier member. The oil pipe 2 opens into a space 24 surrounded by a lower plate 22 and an upper plate 23. The upper plate 23 has a plurality of oil holes 2 through which oil in the oil pan flows.
5 is bored, and oil flows in as shown by arrow C when negative pressure is generated as the oil pump rotates. The lower plate 22 functions as a barrier by being arranged to face the axis of the oil pipe 2, and has the effect of absorbing pressure fluctuations transmitted through the oil pipe 2 and the pressure of oil flowing backward. to do. Therefore, pressure acting impulsively on the bottom wall of the oil pan can be suppressed, so noise caused by membrane vibration on the bottom wall of the oil pan can be reduced.

[Problem that the idea aims to solve]

However, in the conventional device provided with the lower plate as the barrier member described above, a large amount of air bubbles in the oil present in the upper part of the upper plate 23 is sucked into the oil hole 25 formed in the upper plate 23, and the oil pump In some cases, the pumping amount decreased. This is because when the engine is operating, oil is supplied to various parts of the engine, so the oil level is lowered and undulating, causing a large amount of air bubbles to flow in due to the suction force of the oil pump. Furthermore, according to the conventional structure described above, since the lower end opening of the oil pipe 2 is inserted into the space 24 surrounded by the lower plate 22 and the upper plate 23, pressure fluctuations due to rotation of the oil pump and oil leakage are prevented. There was a problem in that the pressure in the space 24 increased due to the backflow, and the inflow resistance of the oil flowing in from the oil hole 25 increased. When the oil inflow resistance increases in this way, it becomes necessary to increase the capacity of the oil pump. In order to increase the capacity of the oil pump, it is possible to increase the size of the oil pump itself or to increase the storage space inside the oil pump, but if the oil pump itself is enlarged, the timing belt will drive the oil pump. If the power increases and the engine drive loss increases, resulting in a decrease in output, or if the storage space is increased, the rate of increase in the storage space during the intake stroke (the degree of expansion of the space relative to the amount of rotation of the rotor) will be large. This makes it easier to induce cavitation. Therefore, an object of the present invention is to reduce the generation of noise by suppressing membrane vibration of an oil pan due to cavitation and backflow of oil, and to suppress an increase in inflow resistance due to an oil strainer.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention is characterized in that the structure of the barrier member provided to reduce membrane vibration on the bottom wall of the oil pan due to cavitation and backflow of oil is changed. Specifically, the lower end openings 9, 90 of the oil pipe 2 whose upper end is connected to the suction port of the oil pump
is attached to oil pipe 2.
In the oil strainer 1 of the engine, which is located in the interior 33 of a space surrounded by the air entrainment prevention member 3 extending in the radial direction of the air entrainment prevention member 3 and the net 4 integrally assembled with the air entrainment prevention member 3, Inside 33 of the strainer, an oil pipe 2 is formed smaller than the air entrainment prevention member 3 and is located close to the air entrainment prevention member 3.
Barrier members 35 and 36 are provided which are arranged opposite to each other in the axis of the oil pipe, and substantially the lower end opening 9 of the oil pipe.
90 is oriented toward the side wall 11b of the oil pan 11.

[Effect]

According to the above means, pressure fluctuations due to cavitation and backflow of oil transmitted through the oil pipe collide with the barrier member, so that they are prevented from being directly transmitted to the bottom wall of the oil pan. The opening oriented toward the side wall quickly opens toward the side wall of the oil pipe. Further, since the barrier member is formed smaller than the air entrainment prevention member, air intrusion from above during oil intake is suppressed. Furthermore, the barrier member is disposed inside the air surrounded by the air entrainment prevention member and the net, and even if the air entrainment prevention member and the barrier member are placed close to each other at the lower end opening of the oil pipe, the net is not removed. Since there is no need to make it small, a sudden increase in oil suction resistance when the mesh becomes clogged is suppressed.

【Example】

Hereinafter, embodiments of the present invention will be described based on the drawings.

[First Embodiment] FIGS. 1, 2, and 3 are vertical sectional views showing the specific structure of an oil strainer according to a first embodiment of the present invention, and FIG. 1 is a main part of the oil strainer. Fig. 2 is a vertical cross-sectional view showing - in Fig. 1.
A vertical cross-sectional view cut along a line and FIG. 3 are vertical cross-sectional views showing a state in which the oil strainer is assembled to an engine. In FIG. 1, the oil strainer 1 has an oil pipe 2 attached to the periphery of the lower end opening 9 of the oil pipe 2.
It consists of a flat plate 3 as an air entrainment prevention member that extends in the radial direction of the air, and a net 4 for removing foreign matter. The flat plate 3 as an air-inclusion prevention member prevents a large amount of air bubbles from getting into the oil pipe 2 even if the oil level above the flat plate 3 drops or becomes undulating. 31, or otherwise integrally attached. Further, the net 4 is assembled using annular clip members, rivets, caulking, or the like. In the interior 33 of the oil strainer 1, a baffle plate 35 is provided as a barrier member that faces the axis of the oil pipe 2. As shown in FIG. 2, this buff-full plate 35 is formed smaller than the flat plate 3, and is welded 42 close to the flat plate 3 via a plurality of stays 41. As shown in FIG. 3, the upper end of the oil pipe 2 is connected to an inlet 14 of an oil pump 13 formed in the cylinder block 12. Oil pressurized by the oil pump 13 is supplied to each sliding part of the engine via the discharge port 15. Further, due to the installation of the buff-full plate 35, the lower end opening 9 of the oil pipe 2 is substantially oriented toward the side wall 11b of the oil pan 11. The operation of this embodiment based on the above configuration will be explained. As shown in FIG. 3, the oil stored in the oil pan 11 is pumped up as shown by arrow D by the rotation of the oil pump 13 and is supplied to each sliding part of the engine through the discharge port 15. As the oil pump 13 rotates, pressure fluctuations (shock waves) occur due to cavitation as described above.
When a backflow of oil occurs, the pressure fluctuation is propagated from the oil pump 13 to the lower end opening 9 of the oil pipe 2, and the oil reaches the lower end opening 9 of the oil pipe 2. However, the oil in which this propagated pressure flows backward may directly propagate and collide with the oil pan bottom wall 11a due to the bump-full plate 35 as a barrier member installed to face the lower end opening 9 of the oil pipe 2. It is avoided, buffered, and released toward the oil pan side wall 11b. Therefore, the oil pan bottom wall 11 is damaged by strong shock waves.
The membrane vibration of a is avoided, and the generation of noise is suppressed. Furthermore, since the stays 41 are simply spaced around the lower end opening 9 of the oil pipe 2, the shock wave is quickly released toward the oil pan side wall 11b. Therefore, the pressure increase around the opening 9 can be suppressed, so that the flow of oil flowing into the oil pipe 2 is not obstructed. Furthermore, since the baffle plate 35 is disposed inside the space 33 surrounded by the flat plate 3 and the net 4 as air-mixing prevention members, even if the flat plate 3 and the buff full plate 35 are placed close to each other, the net 4
The net 4 does not become small and is blocked by foreign objects etc.
Even if there is some clogging, the resistance during oil intake will hardly change. Therefore, for oil suction, oil pump 1
There is no need to increase the capacity of engine 3, and problems such as reduction in engine output, cavitation, and backflow of oil can be avoided.

[Second Embodiment] FIGS. 4 and 5 are longitudinal sectional views showing the structure of an oil strainer according to a second embodiment of the present invention,
FIG. 4 is a longitudinal cross-sectional view showing essential parts of the oil strainer, and FIG. 5 is a view taken along the - line in FIG. 4. In addition, in this example, FIGS. 1 and 2
The same symbols as in FIGS. 1 and 2 are used for components corresponding to the symbols shown in the figures, and specific explanations are omitted. This embodiment differs from the first embodiment in that a buffer plate 45 made of rubber or the like is attached to the upper surface of the buffer plate 35. The buffer plate 45 is provided on the upper surface of the buffer plate 35 at a position opposite to the lower end opening 9 of the oil pipe 2. In this way, by providing the buffer plate 45, it is possible to more effectively absorb pressure fluctuations propagating through the oil pipe 2, and moreover, the pressure released toward the oil pan side wall 11b can also be reduced. can. Therefore, it is possible to further reduce noise caused by pressure fluctuations. In this embodiment, the effect of suppressing the inflow of air bubbles and the flow resistance of inflowing oil is the same as in the first embodiment.

[Third Embodiment] FIG. 6 is a longitudinal sectional view showing the main parts of an oil strainer according to a third embodiment of the present invention. In this embodiment, the barrier member is constructed by making the lower end of the oil pipe 2 a so-called closed end 36. Further, at this time, the lower end opening 90 is formed in the tube wall 2a of the oil pipe 2, and the opening is oriented toward the side wall 11b of the oil pan 11. Regarding other configurations, please refer to the above first embodiment and second embodiment.
Since this is the same as the embodiment, a detailed explanation will be omitted. As in this embodiment, if the lower end of the oil pipe 2 is formed as the closed end 36 and the opening 90 is provided in the pipe wall 2a of the oil pipe 2, a new barrier member is provided and welded to the air entrainment prevention member. There is no need to perform any installation work, and the structure can be simplified. At the same time, since only the lower end of the oil pipe 2 is inserted into the oil strainer 1, the oil strainer 1 does not become larger. Furthermore, since the propagated pressure fluctuations and the reversely flowing oil are immediately released into the oil pan 11 from the opening 90, an increase in pressure near the opening 90 (increase in inflow resistance) is avoided. In this embodiment, the opening 90 formed in the pipe wall 2a is described as a single hole, but a plurality of openings 90 may be formed so as to be oriented toward the four side walls in the oil pan 11. It may be. Although a specific embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and includes various embodiments within the scope of the claims for utility model registration. For example, the barrier member may be directly assembled to the lower end of the oil pipe by welding or the like. With this configuration, as in the third embodiment, it is possible to increase noise and inflow resistance without increasing the size of the oil strainer.

[Effect of the idea]

As described above, according to the present invention, even if pressure fluctuations transmitted through the oil pipe or oil backflow occur, the pressure (impact) is directly applied to the bottom wall of the oil pan.
is not transmitted, and the generation of noise due to membrane vibration of the bottom wall can be suppressed. Further, the pressure buffered by the barrier member is quickly released toward the side wall of the oil pan, thereby avoiding an increase in pressure near the opening at the lower end of the oil pipe and an increase in oil inflow resistance. Furthermore, since a sufficiently large mesh can be provided regardless of the close arrangement of the air entrainment prevention member and the barrier member, a sudden increase in oil inflow resistance when the mesh becomes clogged can be suppressed. Therefore, there is no need to increase the size or capacity of the oil pump, and it is possible to prevent an increase in driving loss and cavitation.

[Brief explanation of the drawing]

1, 2, and 3 are vertical cross-sectional views showing the specific structure of an oil strainer according to a first embodiment of the present invention, and FIG. 1 is a vertical cross-sectional view showing the main parts of the oil strainer, Figure 2 shows − in Figure 1.
FIG. 3 is a longitudinal sectional view taken along a line, FIG. 3 is a longitudinal sectional view showing the oil strainer assembled to the engine, and FIGS. 4 and 5 are the structure of the oil strainer according to the second embodiment of the present invention. FIG. 4 is a longitudinal sectional view showing the main parts of the oil strainer, FIG. 5 is a view cut along the - line in FIG. 4, and FIG. 6 is a third embodiment of the present invention. FIG. 7 and FIG. 8 are vertical cross-sectional views showing the structure of a conventional oil strainer, and FIG. 7 is a vertical cross-sectional view showing the main parts of an oil strainer according to an example. , FIG. 8 is a longitudinal sectional view showing how it is assembled to the engine, FIGS. 9 and 10 are explanatory diagrams schematically showing the operation of the oil pump, and FIG. 11 shows the main points of a conventional device provided with a barrier member. FIG. 1... Oil strainer, 2... Oil pipe, 3... Air mixture prevention member, 4... Net, 9, 9
0... Oil pipe lower end opening, 11... Oil pan, 11a... Oil pan bottom wall, 11b... Oil pan side wall, 13... Oil pump, 35...
Buzzful plate (barrier member), 36... Closed end (barrier member).

Claims (1)

[Scope of Claim for Utility Model Registration] An air entrainment prevention member that is attached to the oil pipe and extends in the radial direction of the oil pipe, and the air entrainment prevention member has a lower end opening of an oil pipe whose upper end is connected to the suction port of an oil pump. In the oil strainer for an engine, which is located inside a space surrounded by a net that is integrally assembled with the An oil strainer for an engine, characterized in that a barrier member is disposed adjacent to the prevention member and facing the axis of the oil pipe, and substantially the lower end opening of the oil pipe is oriented toward the side wall of the oil pan. .