Oil strainer

Abstract

To provide an oil strainer which enables shortening of a rising time of hydraulic pressure without adding a component separately, and can maintain the shortened time without requiring maintenance of the oil strainer.SOLUTION: An oil strainer 2 is used in a passage from an oil pan 1d up to an oil pump 4 out of a lubrication oil circulation path for circulating the lubrication oil to a lubrication-target portion of an internal combustion engine 1. The oil strainer 2 has a suction port connecting portion 3a connected to a suction port 4a of the oil pump 4, an oil immersion portion 12 immersed into the lubrication oil 6 which is accumulated in the oil pan 1d, and a pipe portion 3 connected to the suction port connecting portion 3a from the oil immersion portion 12 while being bent. The pipe portion 3 has a bent portion 3d which is located above the suction port 4a of the oil pump 4 sucking the lubrication oil 6 from the oil pan 1d.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an oil strainer used in a path from an oil pan to an oil pump among lubricating oil circulation paths for circulating lubricating oil in a lubricating portion of an internal combustion engine.

Background Art

[0002] When an internal combustion engine is left standing for a long time with the engine stopped, the lubricating oil that filled the inside of the oil pump and the oil gallery flows backward due to gravity, and the lubricating oil as an oil film covering the surfaces of the components of the main motion system and the valve motion system flows down due to gravity and returns to the oil pan. As a result, the oil pump becomes completely empty of lubricating oil, and the surfaces of the components of the main motion system and the valve motion system are in a state where the oil film has broken. When starting the internal combustion engine in such a state, if it takes a long time for the oil pressure to rise, which is the time from when the driving of the oil pump is started until the supply of lubricating oil to the main motion system and the valve motion system is started, there is a risk of seizure. Therefore, conventionally, techniques for shortening the oil pressure rise time have been devised.

[0003] For example, Patent Document 1 discloses an oil strainer having a check valve for preventing oil from draining. The oil strainer consists of a suction pipe and a wire mesh filter. One end of the suction pipe communicates with the main oil hole side oil passage of the engine cylinder block (an oil pump is arranged in the middle of the oil passage), and the other end is provided with a wire mesh filter and is immersed in the oil in the oil pan. The check valve is arranged in the middle of the suction pipe.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the oil strainer described in Patent Document 1, it is necessary to incorporate a new separate part, a check valve, inside the suction pipe. Also, for example, regular maintenance of the check valve is required.

[0006] An object of the present invention is to provide an oil strainer capable of shortening the hydraulic pressure rise time without adding separate parts and maintaining the shortened time without requiring maintenance.

Means for Solving the Problems

[0007] The oil strainer according to the present disclosure for solving the above problems is an oil strainer used in a path from an oil pan to an oil pump among lubricating oil circulation paths for circulating lubricating oil to a lubricating part in an internal combustion engine, and includes a suction port connection part connected to a suction port of the oil pump, an oil immersion part immersed in the lubricating oil stored in the oil pan, and a pipe part that bends from the oil immersion part and leads to the suction port connection part, and the pipe part has a bent part located above the suction port in the oil pump that sucks up the lubricating oil from the oil pan.

[0008] According to this, when the pressure feeding of the lubricating oil by the oil pump stops with the stop of the internal combustion engine, the lubricating oil flows down to the oil pan by gravity, but the bent part of the pipe part in the oil strainer is located above the suction port of the oil pump. Therefore, after the oil level of the lubricating oil has dropped until it reaches the inside of the bent part, the lubricating oil can no longer flow down to the oil pan. Thus, at least inside the oil pump, the lubricating oil will be retained. As a result, when the operation of the internal combustion engine starts again, the retained lubricating oil is quickly pumped by the oil pump, so the hydraulic pressure rise time is shortened.

[0009] Also, when the oil pump and the oil strainer, or the oil pump itself, are, for example, screw-fastened, the lubricating oil is retained in such a sealed space. Therefore, the lubricating oil will not leak out unless an accident occurs such as a hole appearing or the internal combustion engine itself tilting significantly. In this way, since it is guaranteed that a constant volume of lubricating oil is always retained, it becomes possible to maintain that shortened time without requiring maintenance.

[0010] In the above oil strainer, the suction port connection part is connected to the suction port provided below the oil pump, and the pipe part extends downward from the suction port connection part and then curves upward, and may be connected to the oil immersion part after curving downward at the bending part located above the suction port.

[0011] According to this, in addition to the oil pump, lubricating oil is also retained in the oil strainer (the section from the bending part to the suction port connection part). Therefore, when the operation of the internal combustion engine is started again, more retained lubricating oil is quickly pumped out from the oil pump, so the rise time of the oil pressure is further shortened.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Best Mode for Carrying Out the Invention

[0013] ●[Structure of the oil strainer according to Embodiment 1 (Fig. 1)] As shown in Fig. 1, the internal combustion engine 1 has a cylinder head cover 1a, a cylinder head 1b, a cylinder block 1c, and an oil pan 1d. The cylinder block 1c forms the cylindrical portion of the cylinder and at the same time houses components of the so-called main motion system such as pistons and crankshafts. The cylinder head 1b is provided with a recess serving as a combustion chamber on the joint surface side with the cylinder block 1c, or intake and exhaust ports are formed toward the combustion chamber. Further, the cylinder head 1b supports a so-called valve operating system, which is a mechanism (such as a camshaft, a lash adjuster, and a rocker arm) for opening and closing the intake and exhaust valves that open and close the openings of the intake and exhaust ports.

[0014] Among the components constituting the main motion system housed in the cylinder block 1c and the valve operating system supported by the cylinder head 1b, there are a plurality of portions where metal parts rub against each other (portions that require lubrication and correspond to lubricated portions). The internal combustion engine 1 has a lubrication device that prevents friction in such portions and allows smooth movement. The oil pump 4 is part of the lubrication device. The oil pump 4 pumps lubricating oil to the lubricated portions.

[0015] The cylinder head cover 1a and the oil pan 1d of the internal combustion engine 1 are related to such a lubrication device. The cylinder head cover 1a is provided on the upper part of the cylinder head 1b to prevent the scattering of lubricating oil. The oil pan 1d stores lubricating oil and serves as a tray for the lubricating oil that falls after being supplied to the lubricated portions.

[0016] The oil pump 4 sucks up the lubricating oil accumulated in the oil pan 1d via the oil strainer 2, and pumps the lubricating oil to the lubricating parts of the internal combustion engine 1 through a passage for the lubricating oil called an oil gallery inside the cylinder block 1c and the cylinder head 1b. The lubricating oil sent to each part bounces off or falls due to gravity and returns to the oil pan 1d. Thus, in the internal combustion engine 1, a lubricating oil circulation path for circulating the lubricating oil to the lubricating parts is formed.

[0017] The oil pump 4 is directly connected to the crankshaft of the internal combustion engine 1 and is driven by the rotation of the crankshaft. For example, any of a trochoid pump, a gear pump, or a vane pump may be used. The oil pump 4 has a suction port 4a and a discharge port 4b. The suction port 4a of the oil pump 4 faces the oil level 6a of the lubricating oil 6 accumulated in the oil pan 1d. Therefore, the inflow direction of the lubricating oil sucked from the suction port 4a into the pump interior is substantially perpendicular to the oil level 6a of the lubricating oil 6 accumulated in the oil pan 1d.

[0018] The oil strainer 2 is used in the path from the oil pan 1d to the oil pump 4 in the lubricating oil circulation path. The oil strainer 2 has a pipe part 3. One end of the pipe part 3 is provided with an oil immersion part 12, and the other end is provided with a suction port connection part 3a. The oil immersion part 12 is immersed in the lubricating oil 6 accumulated in the oil pan 1d of the internal combustion engine 1. The suction port connection part 3a is connected to the suction port 4a of the oil pump 4. Note that the oil immersion part 12 is a metal mesh and removes large foreign matters. The suction port connection part 3a is formed as a flange, for example, and is screwed to the flange formed on the suction port 4a of the oil pump 4.

[0019] The pipe part 3 is connected from the oil immersion part 12 to the suction port connection part 3a while being bent. The pipe part 3 is formed, for example, by bending a straight pipe, and has an approach part 3b, a bending part 3d, and a vertically extending part 3e.

[0020] The vertically extending portion 3e is a portion that extends in the vertical direction when the oil strainer 2 is actually mounted on the internal combustion engine 1 (when the suction port connection portion 3a is connected to the suction port 4a of the oil pump 4 and the oil immersion portion 12 is immersed in the lubricating oil 6 in the oil pan 1d). Specifically, the vertically extending portion 3e extends vertically from the oil immersion portion 12, passes over the suction port 4a of the oil pump 4 from bottom to top, and continues to the bent portion 3d. Since the bent portion 3d is continuous from such a vertically extending portion 3e, it is located above the suction port 4a. The bent portion 3d is bent (curved) in a U shape, for example, and continues to the approach portion 3b. The bent portion 3d only needs to be bent so as to change its direction toward the suction port 4a of the oil pump 4 passed over by the vertically extending portion 3e, and may be bent in a V shape, for example. The approach portion 3b extends vertically continuously from the bent portion 3d so as to pass over the suction port 4a of the oil pump 4 from top to bottom, bends (curves) below the suction port 4a and then turns back, and extends vertically again and continues to the suction port connection portion 3a.

[0021] ●[Operation and Effect of Oil Strainer (Fig. 2)] When the pumping of the lubricating oil by the oil pump 4 stops with the stop of the internal combustion engine 1, the lubricating oil that filled the oil strainer 2, the oil pump 4, and the oil gallery flows down to the oil pan 1d by gravity, and the oil level 5a of the lubricating oil 5 also gradually drops downward. Here, since the bent portion 3d of the pipe portion 3 in the oil strainer 2 is located above the suction port 4a, when the oil level 5a of the lubricating oil 5 drops until it reaches the inside of the bent portion 3d, thereafter, the lubricating oil 5 cannot flow down to the vertically extending portion 3e beyond the bent portion 3d. As a result, even after the pumping of the lubricating oil by the oil pump 4 stops, the lubricating oil 5 will be retained in the approach portion 3b and the oil pump 4.

[0022] In this way, with the lubricating oil 5 retained in the approach portion 3b and the oil pump 4, when the operation of the internal combustion engine 1 is started again, the retained lubricating oil 5 is quickly pumped from the oil pump 4. Therefore, the rising time of the oil pressure is shortened. Further, the approach portion 3b and the oil pump 4 in which the lubricating oil 5 is retained are, unlike check valves, sealed spaces fastened by bolts and screws, and as long as there are no holes or the internal combustion engine 1 itself is not greatly tilted (usually, such things rarely occur), the lubricating oil 5 will not leak out, and it is guaranteed that a constant volume of lubricating oil 5 is always retained. Therefore, it is possible to maintain the shortened time without requiring maintenance.

[0023] ●[Structure of oil strainer according to Embodiment 2 (FIG. 3)] Embodiment 2 will be described with reference to FIG. 3. Embodiment 2 is formed in substantially the same manner as Embodiment 1 described above. As shown in FIG. 3, the oil pump 24 is provided with a suction port 24a such that the inflow direction of the lubricating oil sucked into the pump is substantially parallel to the oil surface 6a of the lubricating oil 6 accumulated in the oil pan 1d.

[0024] The oil strainer 22 is used in the path from the oil pan 1d to the oil pump 24 among the lubricating oil circulation paths. The pipe portion 23 is connected from the oil immersion portion 12, while being bent, to the suction port connection portion 3a. The pipe portion 23 is formed, for example, by bending a straight pipe, and has an approach portion 23b, a bent portion 3d, and a vertically extending portion 3e. The approach portion 23b extends continuously from the bent portion 3d in the vertical direction so as to pass over the suction port 24a of the oil pump 24 from top to bottom, bends while being below the suction port 24a and then turns back, extends in the vertical direction again, and finally continues to the suction port connection portion 3a while being bent.

[0025] ●[Structure of oil strainer according to Embodiment 3 (FIG. 4)] Embodiment 3 will be described with reference to FIG. 4. Embodiment 3 is formed in substantially the same manner as Embodiment 1 described above. As shown in FIG. 3, the oil pump 34 has an inlet 34a provided on the upper side together with the outlet 4b. That is, the inlet 34a does not face the oil level 6a of the lubricating oil 6 accumulated in the oil pan 1d, but the inflow direction of the lubricating oil sucked from the inlet 34a into the pump is substantially perpendicular to the oil level 6a.

[0026] The oil strainer 32 is used for the path from the oil pan 1d to the oil pump 34 among the lubricating oil circulation paths. The pipe portion 33 is connected from the oil immersion portion 12 to the inlet connection portion 3a while being bent. The pipe portion 33 is formed, for example, by bending a straight pipe, and has only a bent portion 3d and a vertically extending portion 3e.

[0027] ●[Structure of oil strainer according to Embodiment 4 (FIG. 5)] Embodiment 4 will be described with reference to FIG. 5. Embodiment 4 is formed in substantially the same manner as Embodiment 1 described above. As shown in FIG. 5, the oil strainer 42 according to Embodiment 4 has a solenoid valve 8 in the middle.

[0028] The internal combustion engine system 11 has an internal combustion engine 1 and a control device 7 that controls the opening and closing of the solenoid valve 8 for the internal combustion engine 1. A rotation detection device 9 is provided in the internal combustion engine 1. The rotation detection device 9 is, for example, a rotation sensor, and outputs a detection signal corresponding to the rotation angle of the crankshaft of the internal combustion engine 1 to the control device 7.

[0029] The control device 7 has a CPU, a RAM, a storage device, a timer, etc. The control device 7 receives a control signal from the ignition switch 7a and controls the start or stop of the internal combustion engine 1 and various electrical systems. Signals from the rotation detection device 9 and the oil change switch 7b are input to the control device 7 (CPU), and the control device 7 (CPU) outputs a control signal to the solenoid valve 8.

[0030] The oil strainer 42 is used in the path from the oil pan 1d to the oil pump 4 in the lubricating oil circulation path. The pipe portion 43 is connected from the oil immersion portion 12 to the suction port connection portion 3a and has only the vertically extending portion 3e. The solenoid valve 8 is provided in the middle of the vertically extending portion 3e. Note that the pipe portion 43 may be connected from the oil immersion portion 12 to the suction port connection portion 3a while being bent, but it is desirable that there is no bend that causes oil to remain during oil change (i.e., there is no so-called drain trap).

[0031] The solenoid valve 8 can open and close the valve by energization and is a general one used for controlling the opening and closing of the flow in a pipe through which a fluid (lubricating oil in this embodiment) passes.

[0032] ● [Processing procedure of the control device 7 in the fourth embodiment (Fig. 6)] Next, the flow of the processing of the control device 7 will be described using the flowchart shown in Fig. 6.

[0033] The control device 7 (CPU) repeatedly activates the [solenoid valve opening / closing process] shown in Fig. 6 at, for example, a predetermined time interval (interval of several [ms] to several tens [ms]) and proceeds to step S110.

[0034] In step S110, the control device 7 determines whether or not the internal combustion engine 1 has stopped based on the rotation status of the crankshaft of the internal combustion engine 1 acquired from the rotation detection device 9. If the internal combustion engine 1 has stopped (Yes), the control device 7 proceeds to step S120, and if the internal combustion engine 1 has not stopped (No), the control device 7 proceeds to step S140.

[0035] When proceeding from step S110 to step S140, the control device 7 opens the solenoid valve 8 (the lubricating oil flows through the oil strainer 42 and is sucked up by the oil pump 4 and supplied to each part), and ends the process shown in Fig. 6.

[0036] When the process proceeds to step S120, the control device 7 determines whether or not the oil change switch 7b is ON. The oil change switch 7b is set to ON according to the user's intention when the user changes the oil, and is set to OFF otherwise. When the oil change switch 7b is ON (Yes), the control device 7 proceeds to step S140, and when the oil change switch 7b is not ON (No), the control device 7 proceeds to step S130.

[0037] When the process proceeds from step S120 to step S140, the control device 7 opens the solenoid valve 8 (the lubricating oil falls into the oil pan 1d), and ends the process shown in FIG. 6. Thus, when the oil change switch 7b is ON, the solenoid valve 8 is opened, so that after the internal combustion engine 1 stops, no lubricating oil remains in the oil pump 4 and the oil strainer 42, and the oil can be appropriately changed.

[0038] When the process proceeds to step S130, the control device 7 closes the solenoid valve 8 (the lubricating oil does not fall into the oil pan 1d and is held in the oil strainer 42), and ends the process shown in FIG. 6.

[0039] The exhaust pipe of the internal combustion engine of the present invention is not limited to the appearance, configuration, structure, etc. described in the present embodiment, and various changes, additions, and deletions can be made without changing the gist of the present invention.

Explanation of Reference Numerals

[0040] 1 Internal combustion engine 1a Cylinder head cover 1b Cylinder head 1c Cylinder block 1d Oil pan 2, 22, 32, 42 Oil strainer 3, 23, 33, 43 Pipe portion 3a Suction port connection portion 3b, 23b Approach portion 3d Bending portion 3e Vertically extending portion 4, 24, 34 Oil pump 4a, 24a, 34a suction ports 4b discharge port 6 lubricating oil 6a oil level 7 control device 7a ignition switch 7b oil change switch 8 solenoid valve 9 rotation detection device 11 internal combustion engine system 12 oil immersion part

Claims

1. An oil strainer used in a path from an oil pan to an oil pump among lubricating oil circulation paths for circulating lubricating oil in a lubricating part of an internal combustion engine, comprising: a suction port connection part connected to a suction port of the oil pump; an oil immersion part immersed in the lubricating oil stored in the oil pan; a pipe part that bends from the oil immersion part and connects to the suction port connection part; and having the pipe part has a bent part located above the suction port in the oil pump that sucks up the lubricating oil from the oil pan; the suction port connection part is connected to the suction port provided below the oil pump; the pipe part extends downward from the suction port connection part, then curves upward, curves downward at the bent part located above the suction port, and then is connected to the oil immersion part. Oil strainer.

2. An oil strainer used in a path from an oil pan to an oil pump among lubricating oil circulation paths for circulating lubricating oil in a lubricating part of an internal combustion engine, comprising: a suction port connection part connected to a suction port of the oil pump; an oil immersion part immersed in the lubricating oil stored in the oil pan; a pipe part that bends from the oil immersion part and connects to the suction port connection part; and having the pipe part has a lower bent part that extends downward and then curves upward on the side closer to the oil pump; has an upper bent part that extends upward and then curves downward on the side farther from the oil pump and is located above the suction port. Oil strainer.

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