oil supply device

Abstract

To provide an oil supply device that can prevent malfunctions caused by the accumulation of sludge in the relief valve. [Solution] The oil supply device comprises a pump that supplies oil to an internal combustion engine, a relief valve that adjusts the oil pressure in the oil passage between the oil outlet of the pump and the internal combustion engine, and a relief valve control unit that has a sludge removal mode and forcibly opens and closes the relief valve when the sludge removal mode is active.

Description

Technical Field

[0001] The present disclosure relates to an oil supply device for supplying oil to an internal combustion engine.

Background Art

[0002] Conventionally, as an oil supply device for supplying oil as lubricating oil to an internal combustion engine, there is, for example, one disclosed in Patent Document 1. The oil supply device described in Patent Document 1 has an oil pump (hereinafter, may be simply referred to as a "pump"). The pump is driven by the power of, for example, an internal combustion engine (hereinafter, may also be referred to as an "engine"). The pump supplies the oil in an oil pan or a reservoir tank to the engine. Specifically, the oil is supplied from the pump to each part of the engine via an oil filter, an oil cooler, and an oil gallery.

[0003] Here, an electronically controlled relief valve (such as a needle valve) is provided in the oil passage from the pump to the engine. By controlling the opening and closing of the electronically controlled relief valve by a control unit, the oil pressure supplied to the engine is properly controlled. As a result, improvement in fuel consumption, extension of the engine life, etc. can be achieved. The electronically controlled relief valve and its control are described in, for example, Patent Document 2.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, the oil drawn up by the pump contains sludge, which consists of metal particles and other materials generated by the friction of engine parts. If this sludge accumulates in the relief valve, it may cause the relief valve to malfunction.

[0006] If the relief valve malfunctions and the oil pressure remains above the appropriate range, it can lead to decreased engine fuel efficiency and other problems. Conversely, if the relief valve malfunctions and the oil pressure remains below the appropriate range, it can lead to engine failure and other problems.

[0007] This disclosure has been made in consideration of the above points and provides an oil supply device that can prevent malfunctions caused by the accumulation of sludge in the relief valve. [Means for solving the problem]

[0008] One embodiment of the oil supply device disclosed herein is: An oil supply device that supplies oil to an internal combustion engine, A pump that supplies oil to the internal combustion engine, A relief valve that adjusts the oil pressure in the oil passage between the oil outlet of the pump and the internal combustion engine, A relief valve control unit that has a sludge removal mode and forcibly opens and closes the relief valve when in the sludge removal mode, It is equipped with. [Effects of the Invention]

[0009] According to this disclosure, an oil supply system can be realized that can prevent malfunctions caused by the accumulation of sludge in the relief valve. [Brief explanation of the drawing]

[0010] [Figure 1] Schematic diagram showing the configuration of the oil supply device of the embodiment. [Figure 2] Diagram showing the fully closed state of the relief valve. [Figure 3] Diagram showing the fully open state of the relief valve. [Figure 4] Figure showing the state where sludge has accumulated in the relief valve [Figure 5] Figure showing the state where sludge has been removed [Figure 6] Flowchart for explaining the operation of the control unit in the present embodiment

Mode for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0012] FIG. 1 is a schematic diagram showing the configuration of an oil supply device 100 according to an embodiment. The oil supply device 100 is mounted on a vehicle having a diesel engine (hereinafter referred to as "engine") 200 as an internal combustion engine. Note that the oil supply device 100 can also be used for a vehicle having a gasoline engine.

[0013] The oil supply device 100 includes an oil pan 101, a pump 102, a supply oil passage 103, a discharge oil passage 104, an oil filter 105, and the like.

[0014] The oil stored in the oil pan 101 as lubricating oil is sucked by the pump 102 and supplied to the engine 200 via the supply oil passage 103. The oil discharged from the engine 200 is returned to the oil pan 101 via the discharge oil passage 104.

[0015] Note that the oil supplied to the engine 200 via the supply oil passage 103 is sent to an oil gallery (not shown) extending in the cylinder row direction in the cylinder block (not shown) of the engine 200. The oil gallery communicates with each part to be lubricated and cooled in the engine 200.

[0016] The pump 102 rotates, for example, by the power supplied from the engine 200. The oil filter 105 removes sludge, wear powder, dust, and the like from the oil.

[0017] In addition to such a configuration, the oil supply device 100 includes an oil relief unit 110 and a control unit 120.

[0018] The oil relief unit 110 includes an oil passage 111 and an electronically controlled relief valve 112. The oil passage 111 includes a connection oil passage 111-1 connected to the supply oil passage 103 and a relief oil passage 111-2 connected to the discharge oil passage 104. The relief valve 112 is provided at the connection position between the connection oil passage 111-1 and the relief oil passage 111-2.

[0019] The relief valve 112 adjusts the opening degree of the relief oil passage 111-2 with respect to the connection oil passage 111-1 so that the oil pressure in the connection oil passage 111-1, and thus the supply oil passage 103, reaches a desired value. Specifically, the relief valve 112 is controlled such that the opening degree increases as the oil pressure in the supply oil passage 103 (connection oil passage 111-1) becomes higher than the target oil pressure, increasing the amount of oil flowing through the relief oil passage 111-2. As a result, the pressure of the oil in the supply oil passage 103 (connection oil passage 111-1) is maintained at the target value. This target value is changed according to the operating load state of the engine 200, as described below.

[0020] The opening degree of the electronically controlled relief valve 112 provided in the oil relief unit 110 is controlled by the control unit 120. The control unit 120 sends a control signal to the relief valve 112 and controls the opening degree of the relief valve 112 based on the detection results of a hydraulic pressure sensor 131 that detects the hydraulic pressure in the oil gallery of the engine 200, an accelerator opening sensor 132 that detects the opening degree of the accelerator, and an engine rotation sensor 133 that detects the engine rotation speed.

[0021] The control unit 120 includes a relief valve control unit 121, an operating state acquisition unit 122, and a responsiveness monitoring unit 123. The control unit 120 includes a processor as its main component, consisting of a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), etc. The processor realizes the functions of the relief valve control unit 121, the operating state acquisition unit 122, and the responsiveness monitoring unit 123 by executing a predetermined program. Note that all or part of the relief valve control unit 121, the operating state acquisition unit 122, and the responsiveness monitoring unit 123 may be formed by hardwired circuits such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array).

[0022] The relief valve control unit 121 of the control unit 120, for example, uses feedback control to adjust the opening degree of the relief valve 112 based on the deviation between the set target gallery hydraulic pressure and the actual gallery hydraulic pressure input from the hydraulic pressure sensor 131, thereby setting the actual gallery hydraulic pressure to the target gallery hydraulic pressure.

[0023] The specific control of the relief valve control unit 121 will now be explained. When the engine 200 is operating under high load, the relief valve control unit 121 increases the hydraulic pressure supplied to the engine 200 by fully closing or reducing the opening of the relief valve 112, as shown in Figure 2. Conversely, when the engine 200 is operating under low load, the relief valve control unit 121 decreases the hydraulic pressure supplied to the engine 200 by fully opening or increasing the opening of the relief valve 112, as shown in Figure 3.

[0024] In this disclosure, the method of controlling the relief valve by the relief valve control unit 121 is not limited to this. Essentially, the opening degree of the relief valve 112 should be controlled so that the hydraulic pressure supplied to the engine 200 is optimized.

[0025] Here, Figure 4 shows a state in which sludge 300 has accumulated in the relief valve 112. When sludge 300 accumulates in the relief valve 112, the relief valve 112 malfunctions. As a result, the opening degree of the relief valve 112 does not become as instructed by the relief valve control unit 121, or the ability to track the opening degree deteriorates, which may lead to a decrease in the fuel efficiency of the engine 200 or even engine failure of the engine 200.

[0026] Taking this into consideration, the relief valve control unit 121 of this embodiment has a sludge removal mode, and in this sludge removal mode, it is configured to forcibly open and close the relief valve 112. Here, forcibly opening and closing the relief valve 112 means opening and closing the relief valve 112 for the purpose of removing sludge 300, independently of the optimization operation of the hydraulic pressure supplied to the engine 200 as described above (which may also be called feedback control). In other words, forcibly opening and closing the relief valve 112 can also be said to mean opening and closing the relief valve 112 regardless of the target gallery hydraulic pressure.

[0027] In this embodiment, the relief valve control unit 121 has a normal mode in which the relief valve 112 is opened and closed based on a target gallery hydraulic pressure, and a sludge removal mode in which the relief valve 112 is opened and closed primarily for the purpose of removing sludge 300.

[0028] In sludge removal mode, the relief valve control unit 121 forcibly opens and closes the relief valve 112 over a wider range than in normal mode. That is, for example, in normal mode, the relief valve 112 is opened and closed between the position shown in Figure 2 and the position shown in Figure 3, whereas in sludge removal mode, the relief valve 112 is operated over a wider range in the left-right direction of the figure. For example, in normal mode, the relief valve 112 is opened and closed within a range of 0 to 40% opening, whereas in sludge removal mode, the relief valve 112 is opened and closed within a range of 0 to 80% opening. In addition, in sludge removal mode, the relief valve control unit 121 may forcibly open and close the relief valve 112 at a faster speed than in normal mode.

[0029] In this way, the sludge 300 accumulated in the relief valve 112 is removed, and as shown in Figure 5, the sludge 300 can be discharged through the relief oil passage 111-2.

[0030] Figure 6 is a flowchart illustrating the operation of the control unit 120 in this embodiment. The control unit 120 executes the flow shown in Figure 6 while the engine 200 is running.

[0031] In step S11, the control unit 120 determines whether the engine 200 is in a low-load operating state. Specifically, the operating state acquisition unit 122 determines whether the engine is in a low-load operating state based on the engine speed, accelerator opening, etc. The operating state acquisition unit 122 determines that the engine is in a low-load operating state if the engine speed is lower than a predetermined threshold, and / or if the accelerator opening is smaller than a predetermined threshold.

[0032] If the control unit 120 determines in step S11 that low-load operation is occurring (step S11; YES), it proceeds to step S12. In step S12, the control unit 120 enters sludge removal mode and the relief valve control unit 121 forcibly opens and closes the relief valve 112. This removes the sludge 300.

[0033] In the following step S13, the control unit 120 determines whether the hydraulic response is sufficient. Specifically, the response monitoring unit 123 monitors the response of the relief valve 112 based on the detection result of the hydraulic sensor 131. Here, if the fluctuation of the actual gallery hydraulic pressure detected by the hydraulic sensor 131 is small in response to the control of the relief valve control unit 121, it can be said that the response is low. If the fluctuation of the actual gallery hydraulic pressure detected by the hydraulic sensor 131 (i.e., the response) in response to the control of the relief valve control unit 121 is lower than a predetermined threshold, the response monitoring unit 123 determines that the hydraulic response is insufficient (step S13; NO) and returns to step S11.

[0034] In this way, the control unit 120 repeats the loop of steps S11-S12-S13-S11 until the hydraulic response is sufficient, thereby continuing to execute the sludge removal mode until the hydraulic response is sufficient.

[0035] In this embodiment, by performing step S11, the execution of the sludge removal mode is limited to when the engine 200 is operating at a low load. This prevents the oil pressure supplied to the engine 200 from falling below the target oil pressure, while allowing the sludge 300 to be removed at an appropriate timing.

[0036] In other words, if the sludge removal mode is executed during high-load operation, the oil pressure supplied to the engine 200 may not reach the required oil pressure (target oil pressure), resulting in a shortage of oil supplied to the engine 200 and potentially causing the engine 200 to seize up. In contrast, as in this embodiment, if the sludge removal mode is executed during low-load operation when the required oil pressure (target oil pressure) is already low, even if oil is discharged into the relief oil passage 112-2 due to the sludge removal mode, the possibility of a shortage of oil supplied to the engine 200 is small.

[0037] In this embodiment, the execution of the sludge removal mode was described only when the engine 200 is operating at a low load. However, it may also be performed when the engine is operating at a high load. For example, if the discharge capacity of the pump 102 is large enough to ensure the necessary hydraulic pressure during high-load operation even when the sludge removal mode is performed, the sludge removal mode may be performed during high-load operation.

[0038] As described above, this embodiment adopts the following configuration.

[0039] (1) One embodiment of the oil supply device 100 of this embodiment is an oil supply device 100 that supplies oil to an internal combustion engine (engine 200), comprising: a pump 102 that supplies oil to the internal combustion engine (engine 200); a relief valve 112 that adjusts the oil pressure in the oil passage (supply oil passage 103) between the oil outlet of the pump 102 and the internal combustion engine (engine 200); and a relief valve control unit 121 that has a sludge removal mode and forcibly opens and closes the relief valve 112 when in the sludge removal mode.

[0040] This makes it possible to realize an oil supply device 100 that can prevent malfunctions caused by the accumulation of sludge in the relief valve 112.

[0041] (2) In one embodiment of the oil supply device 100 of this embodiment, the relief valve control unit 121 executes a sludge removal mode when the required oil pressure of the internal combustion engine (engine 200) is low (low load operation state).

[0042] (3) In one embodiment of the oil supply device 100 of this embodiment, the relief valve control unit 121 has a sludge removal mode and a normal mode, and in the sludge removal mode, the relief valve 112 is forcibly opened and closed over a wider range than in the normal mode.

[0043] (4) One embodiment of the oil supply device 100 of this embodiment further includes a monitoring unit (response monitoring unit 123) that monitors the responsiveness of changes in hydraulic pressure in the internal combustion engine (engine 200) to changes in the opening and closing of the relief valve 112, and the relief valve control unit 121 executes a sludge removal mode when the responsiveness is lower than a predetermined threshold.

[0044] The embodiments described above are merely examples of how the present disclosure may be implemented, and the technical scope of the present invention should not be limited by them. In other words, the present disclosure can be implemented in various ways without departing from its essence or its main features. [Industrial applicability]

[0045] This disclosure is broadly applicable to oil supply devices that adjust the amount of oil supplied to an internal combustion engine using a relief valve. [Explanation of symbols]

[0046] 100 Oil supply device 101 Oil Pan 102 pump 103 Supply oil channels 104 Discharge oil path 105 Oil filter 110 Oil relief section 111 Oil road 111-1 Connecting oil channel 111-2 Relief oil channel 112 Relief Valve 120 Control Unit 121 Relief Valve Control Unit 122 Operating status acquisition unit 123 Responsiveness Monitoring Unit 131 Hydraulic sensor 132 Accelerator position sensor 133 Engine speed sensor

Claims

1. An oil supply device that supplies oil to an internal combustion engine, A pump that supplies oil to the internal combustion engine, A relief valve that adjusts the oil pressure in the oil passage between the oil outlet of the pump and the internal combustion engine, A relief valve control unit that has a sludge removal mode and forcibly opens and closes the relief valve when in the sludge removal mode, An oil supply device equipped with the following features.

2. The relief valve control unit executes the sludge removal mode when the required oil pressure in the internal combustion engine is low during operation. The oil supply device according to claim 1.

3. The relief valve control unit has a sludge removal mode and a normal mode, and in the sludge removal mode, it forcibly opens and closes the relief valve over a wider range than in the normal mode. The oil supply device according to claim 1.

4. The system further includes a monitoring unit that monitors the responsiveness of changes in hydraulic pressure in the internal combustion engine to changes in the opening and closing of the relief valve. The relief valve control unit executes the sludge removal mode when the responsiveness is lower than a predetermined threshold. The oil supply device according to claim 1.

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