Engine system

Abstract

The objective is to provide an engine system that can notify the user of abnormalities in the oil piping and blow-by gas piping. [Solution] An engine system comprising: an engine; a throttle valve provided in the intake manifold of the engine; an oil tank storing lubricating oil for the engine; an oil pipe that flows the oil from the oil tank to the engine and blow-by gas from the engine to the oil tank; a first blow-by gas pipe that flows the blow-by gas from the oil tank downstream of the throttle valve in the intake manifold; a pressure sensor that detects the pressure in the oil tank; and a notification control device that performs notification processing to notify the user that an abnormality has occurred in at least one of the oil pipe and the first blow-by gas pipe when the deviation of the pressure in the oil tank detected by the pressure sensor from the normal pressure exceeds a threshold.

Description

Technical Field

[0001] The present invention relates to an engine system.

Background Art

[0002] An oil tank storing oil for lubricating an engine communicates with the engine through an oil pipe and communicates with a portion downstream of the throttle valve in the intake pipe through a blow-by gas pipe (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] If the engine operation continues when any abnormality occurs in such an oil pipe or blow-by gas pipe, there is a risk that blow-by gas will continue to be released into the atmosphere.

[0005] Therefore, an object of the present invention is to provide an engine system that can notify a user of an abnormality in an oil pipe or a blow-by gas pipe.

Means for Solving the Problems

[0006] The above objective can be achieved by an engine system comprising: an engine; a throttle valve provided in the intake manifold of the engine; an oil tank storing lubricating oil for the engine; an oil pipe that flows the oil from the oil tank to the engine and blow-by gas from the engine to the oil tank; a first blow-by gas pipe that flows the blow-by gas from the oil tank downstream of the throttle valve in the intake manifold; a pressure sensor that detects the pressure in the oil tank; and a notification control device that performs notification processing to notify the user that an abnormality has occurred in at least one of the oil pipe and the first blow-by gas pipe when the deviation of the pressure in the oil tank detected by the pressure sensor from the normal pressure exceeds a threshold.

[0007] The system includes a compressor for a supercharger provided in the intake pipe and located upstream of the throttle valve, and a second blow-by gas pipe that flows the blow-by gas from the oil tank to the upstream side of the compressor in the intake pipe when the engine is operating in the supercharged region, and the notification control device may perform the notification process to notify the user that an abnormality has occurred in at least one of the oil pipe, the first blow-by gas pipe, and the second blow-by gas pipe when the deviation amount is greater than or equal to the threshold. [Effects of the Invention]

[0008] According to the present invention, an engine system can be provided that can notify the user of abnormalities in oil piping or blow-by gas piping. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram of the engine system of the first embodiment. [Figure 2] This is a flowchart illustrating an anomaly notification control system. [Figure 3] This is a timing chart showing the changes in tank pressure when an abnormality occurs. [Figure 4]This is a schematic diagram of the engine system of the second embodiment. [Modes for carrying out the invention]

[0010] [First Embodiment] Figure 1 is a schematic diagram of the engine system of the first embodiment. The engine system is mounted, for example, in a vehicle. The engine system includes an engine 1, an oil tank 10, an ECU (Electronic Control Unit) 20, and a display 30. Engine 1 is an inline engine, but is not limited to that. Also, engine 1 is a gasoline engine, but may be a diesel engine.

[0011] An intake manifold 4 is connected to engine 1. The intake manifold 4 has a throttle valve 6 and an intake manifold 2 on the upstream to downstream side. The intake manifold 2 is connected to the intake port of engine 1. An exhaust manifold is also connected to engine 1.

[0012] A fresh air intake pipe 16 is provided, connecting the intake manifold 4 upstream of the throttle valve 6 to the engine 1. When the pressure inside the engine 1 falls below atmospheric pressure, fresh air is introduced into the engine 1 via the fresh air intake pipe 16, preventing negative pressure from forming inside the engine 1.

[0013] The ECU20 is primarily composed of a computer including a CPU (Central Processing Unit) and volatile and non-volatile memory such as RAM (Random Access Memory) and ROM (Read Only Memory). The ECU20 is an example of a notification control device.

[0014] The ECU 20 is connected to an ignition switch 21, a pressure sensor 22, an intake pressure sensor 23, and a display 30. The ignition switch 21 detects the on / off state of the ignition. The pressure sensor 22 detects the tank pressure, which is the pressure in the gas-filled space within the oil tank 10. The intake pressure sensor 23 detects the intake pressure in the intake manifold 2. The ECU 20 adjusts the opening degree of the throttle valve 6 according to the operating state of the engine 1. The display 30 is provided, for example, on the instrument panel of the vehicle.

[0015] The oil tank 10 is a dry-sump type tank that stores oil for lubricating the engine 1. The oil tank 10 is connected to the engine 1 via oil piping 10a. When the scavenging pump P1 is driven, the oil used in the engine 1 flows into the oil tank 10 via oil piping 10a. Blow-by gas generated in the engine 1 also flows into the oil tank 10 via oil piping 10a. The scavenging pump P1 is a mechanical pump that is driven in conjunction with the rotation of the crankshaft 1a of the engine 1. The oil stored in the oil tank 10 is pumped to each lubrication part of the engine 1 by a feed pump P2 provided in the engine 1.

[0016] The lower part of the oil tank 10 stores oil separated from blow-by gas. The upper part of the blow-by tank 10 accumulates blow-by gas. A blow-by gas pipe 15 is provided connecting the upper part of the oil tank 10 to the intake manifold 2. The blow-by gas pipe 15 is an example of a first blow-by gas pipe. A check valve 14 is provided in the blow-by gas pipe 15. The check valve 14 allows gas to flow from the oil tank 10 to the intake manifold 2, but restricts gas flow from the intake manifold 2 to the oil tank 10.

[0017] During the operation of the engine 1, the pressure in the oil tank 10 becomes higher than the pressure in the intake manifold 2. As a result, the check valve 14 opens, and the blow-by gas in the oil tank 10 is supplied to the combustion of the engine 1 via the blow-by gas pipe 15.

[0018] In this way, the scavenging pump P1, the oil pipe 10a, and the oil tank 10 recover the oil used in the engine 1. Also, the scavenging pump P1, the oil pipe 10a, the oil tank 10, and the blow-by gas pipe 15 return the blow-by gas generated in the engine 1 to the engine 1. Therefore, these mechanisms are mechanisms for realizing the recovery of oil and the reflux of blow-by gas. Incidentally, the ECU 20 can estimate the flow rate of the blow-by gas flowing through the blow-by gas pipe 15 based on the difference in pressure detected by the pressure sensor 22 and the intake pressure sensor 23.

[0019] [Abnormal notification control] FIG. 2 is a flowchart illustrating the abnormal notification control. This flowchart is repeatedly executed while the ignition is on. The ECU 20 determines whether or not the deviation amount of the internal pressure of the tank detected by the pressure sensor 22 from the normal pressure is equal to or greater than the threshold value (step S1). The deviation amount is a value obtained by subtracting the internal pressure of the tank detected by the pressure sensor 22 from the normal pressure. The normal pressure is the minimum value of the internal pressure of the tank that can be obtained during the drive of the engine 1 when there are no holes or disconnections in the oil pipe 10a or the blow-by gas pipe 15, and is a pressure higher than the atmospheric pressure. The threshold value is the pressure corresponding to the decrease from the normal pressure when a hole occurs in the oil pipe 10a or the blow-by gas pipe 15, or when the oil pipe 10a or the blow-by gas pipe 15 becomes disconnected. If the result in step S1 is No, this control ends.

[0020] When the answer is Yes in step S1, it is considered that at least one of the oil pipe 10a and the blow-by gas pipe 15 has a hole, or at least one of the oil pipe 10a and the blow-by gas pipe 15 has fallen off, resulting in the tank internal pressure dropping to near atmospheric pressure. In this case, the blow-by gas in the oil tank 10 is released to the atmosphere. Therefore, the ECU 20 executes an abnormality notification process to notify the user that an abnormality has occurred in at least one of the oil pipe 10a and the blow-by gas pipe 15 (step S2). The ECU 20 may notify the user by displaying the message on, for example, the display 30, or may notify the user through the MIL (Malfunction Indicator Light) or the speaker.

[0021] Figure 3 is a timing chart showing the transition of the tank internal pressure when an abnormality occurs. For example, when a hole opens in the blow-by gas pipe 15, the tank internal pressure gradually decreases with respect to the normal pressure (time t1). The deviation amount of the tank internal pressure from the normal pressure gradually increases, and when the deviation amount becomes equal to or greater than the threshold value, the above-described abnormality notification process is executed (time t2). Such notification can prompt the user to stop the engine 1 for inspection. By stopping the engine 1, the release of blow-by gas to the atmosphere can be suppressed.

[0022] [Second Embodiment] Figure 4 is a schematic diagram of the engine system of the second embodiment. In the engine system of the second embodiment, the engine 1 has a supercharger. Therefore, the compressor 5 of the supercharger is provided upstream of the throttle valve 6 in the intake pipe 4. In addition, a blow-by gas pipe 13 is provided that connects the upper part of the oil tank 10 to the side of the intake pipe 4 upstream of the compressor 5. The blow-by gas pipe 13 is an example of a second blow-by gas pipe. A check valve 12 is provided in the blow-by gas pipe 13. The check valve 12 allows the flow of gas from the oil tank 10 to the side of the intake pipe 4 upstream of the compressor 5, but restricts the flow of gas from the side of the intake pipe 4 upstream of the compressor 5 to the oil tank 10. In addition, the fresh air intake pipe 16a connects the side of the intake pipe 4 upstream of the compressor 5 to the engine 1.

[0023] During natural aspiration, the pressure in the oil tank 10 is higher than the pressure in the intake manifold 2. This causes the check valve 14 to open, and the blow-by gas in the oil tank 10 is supplied to the combustion of the engine 1 via the blow-by gas pipe 15. During supercharging, the pressure in the oil tank 10 is higher than the pressure upstream of the compressor 5. This causes the check valve 12 to open, and the blow-by gas in the oil tank 10 is supplied to the combustion of the engine 1 via the blow-by gas pipe 13.

[0024] If the internal tank pressure detected by the pressure sensor 22 is lower than the normal range, the ECU 20a performs an abnormality notification process to inform the user that an abnormality has occurred in at least one of the oil pipe 10a, blow-by gas pipe 15, and blow-by gas pipe 13.

[0025] Although embodiments of the present invention have been described in detail above, the present invention is not limited to these specific embodiments, and various modifications and changes are possible within the scope of the gist of the present invention as described in the claims. [Explanation of symbols]

[0026] 1 Engine 4. Intake pipe 10 Oil Tanks 12, 14 Check valve 15. First blow-by gas piping 13. Second blow-by gas piping 20, 20a ECU (Notification Control Unit) 22 Pressure Sensor

Claims

1. The engine and A throttle valve provided in the intake manifold of the aforementioned engine, An oil tank for storing lubricating oil for the engine, An oil piping system that allows oil to flow from the oil tank to the engine and blow-by gas to flow from the engine to the oil tank, A first blow-by gas pipe that flows the blow-by gas from the oil tank downstream of the throttle valve in the intake pipe, A pressure sensor for detecting the pressure inside the oil tank, A notification control device that, when the amount of deviation of the pressure in the oil tank detected by the pressure sensor from the normal pressure exceeds a threshold, performs a notification process to notify the user that an abnormality has occurred in at least one of the oil piping and the first blow-by gas piping, An engine system equipped with [the following features].

2. A compressor of a supercharger is provided in the intake pipe and is located upstream of the throttle valve, The engine is provided with a second blow-by gas pipe that flows the blow-by gas from the oil tank to the upstream side of the compressor in the intake pipe when the engine is operating in the supercharging region. The engine system according to claim 1, wherein the notification control device performs the notification process to notify the user that an abnormality has occurred in at least one of the oil pipe, the first blow-by gas pipe, and the second blow-by gas pipe when the deviation amount is greater than or equal to the threshold.

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