Engine

Abstract

To separate water content from an engine oil.SOLUTION: An engine includes: an engine body having a crank shaft; an oil tank having rotary vanes; and a power transmission mechanism having an input shaft connected to the crank shaft and an output shaft connected to the rotary vanes. When a rotational speed of the input shaft is above a threshold value, the power transmission mechanism is alternately switched to be between in a drive state where the rotation is transmitted from the input shaft to the output shaft and a non-drive state where the rotation is not transmitted from the input shaft to the output shaft.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to an engine.

Background Art

[0002] Vehicles such as automobiles are equipped with an engine, which is an internal combustion engine (see Patent Document 1). In an engine, moisture is generated when fuel such as gasoline or hydrogen is burned, so there is a risk that the moisture mixes with the engine oil and degrades the oil performance. Therefore, a technique has been proposed in which the engine oil is rotated using the rotational force of the crankshaft to separate the moisture from the engine oil (see Patent Document 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, as a method of separating moisture from engine oil, it is conceivable to flow the engine oil stored in the tank by a rotating blade. At this time, if an attempt is made to rotate the rotating blade by the crankshaft, there is a risk that the rotational speed of the rotating blade will also greatly fluctuate with the fluctuation of the engine speed. Thus, since the large fluctuation in the rotational speed of the rotating blade is a factor that stirs the engine oil, it is required to gently flow the engine oil while rotating the rotating blade at a substantially constant speed to separate the moisture from the engine oil.

Means for Solving the Problems

[0005] According to the present disclosure, an engine includes an engine body having a crankshaft, an oil tank having rotating blades, and a power transmission mechanism including an input shaft connected to the crankshaft and an output shaft connected to the rotating blades. The engine has a first oil passage connected to the engine body and the oil tank and supplying engine oil from the engine body to the oil tank. The engine has a second oil passage connected to the engine body and the oil tank and supplying engine oil from the oil tank to the engine body. The power transmission mechanism alternately repeats a driving state in which rotational force is transmitted from the input shaft to the output shaft and a non-driving state in which rotational force is not transmitted from the input shaft to the output shaft when the rotational speed of the input shaft exceeds a threshold value.

Advantages of the Invention

[0006] According to the present disclosure, moisture can be separated from engine oil.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 4A

Figure 4B

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Mode for Carrying Out the Invention

[0008] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the following description, the same or substantially the same configurations and elements are denoted by the same reference numerals, and repeated descriptions thereof are omitted.

[0009] <Vehicle> FIG. 1 is a diagram showing an example of a vehicle 11 equipped with an engine 10 according to an embodiment of the present disclosure. As shown in FIG. 1, the vehicle 11 has a power unit 13 including an engine 10 and a transmission 12. The drive shaft 14 of the power unit 13 is connected to the wheels 17 via a propeller shaft 15 and a differential mechanism 16. Note that the illustrated power unit 13 is a power unit for rear-wheel drive, but it is not limited thereto, and it may be a power unit for front-wheel drive or all-wheel drive.

[0010] <Engine> FIG. 2 is a diagram showing an example of the engine 10. As shown in FIG. 2, the engine 10 has an engine body 20, a water separation system 40 attached to the engine body 20, and a control system 70 for controlling the engine body 20 and the water separation system 40. Hereinafter, the configurations of the engine body 20, the water separation system 40, and the control system 70 will be described in this order.

[0011] <Engine Body> As shown in FIG. 2, the engine body 20 that constitutes the engine 10 has a cylinder block 21 and a cylinder head 22. A piston 23 is assembled to the cylinder block 21 so as to be reciprocable, and a crankshaft 24 connected to the piston 23 is rotatably supported. Further, an oil pan 25 is provided at the lower part of the cylinder block 21, and engine oil 100 is stored in the oil pan 25. Note that the engine oil 100 in the oil pan 25 is supplied from a strainer 26 to each sliding part in the engine body 20 via an oil pump (not shown).

[0012] An intake valve 31 that opens and closes an intake port 30 is assembled to the cylinder head 22, and an exhaust valve 33 that opens and closes an exhaust port 32 is assembled. Further, an intake camshaft 34 that drives the intake valve 31 is assembled to the cylinder head 22, and an exhaust camshaft 35 that drives the exhaust valve 33 is assembled. Furthermore, an injector 37 that injects fuel into the combustion chamber 36 is assembled to the cylinder head 22, and a spark plug 38 that ignites the air-fuel mixture in the combustion chamber 36 is assembled.

[0013] <Water Separation System> As shown in FIG. 2, the water separation system 40 that constitutes the engine 10 has an oil tank 41 that stores engine oil and a drain tank 42 that stores water separated from the engine oil. An injection port 41a is formed at the upper part of the oil tank 41, and a return port 41b and a drain port 41c are formed at the lower part of the oil tank 41.

[0014] The engine body 20 and the oil tank 41 are connected via an oil injection passage (first oil passage) 43 composed of an upstream pipe 43a and a downstream pipe 43b. An electric oil pump (electric pump) 44 is provided in the oil injection passage 43. The suction port 44i of the electric oil pump 44 is connected to the oil pan 25 of the engine body 20 via the upstream pipe 43a, and the discharge port 44o of the electric oil pump 44 is connected to the injection port 41a of the oil tank 41 via the downstream pipe 43b.

[0015] The engine body 20 and the oil tank 41 are connected via a return passage (second oil passage) 45 composed of return pipes 45a and 45b. A return valve (first on-off valve) 46 that operates between a communicating state and a shut-off state is provided in the return passage 45. The input port 46i of the return valve 46 is connected to the return port 41b of the oil tank 41 via the return pipe 45a, and the output port 46o of the return valve 46 is connected to the cylinder block 21 of the engine body 20 via the return pipe 45b.

[0016] The oil tank 41 and the drain tank 42 are connected via a drain passage (drainage passage) 47 composed of drain pipes 47a and 47b. A drain valve (second on-off valve) 48 that operates between a communicating state and a shut-off state is provided in the drain passage 47. The input port 48i of the drain valve 48 is connected to the drain port 41c of the oil tank 41 via the drain pipe 47a, and the output port 48o of the drain valve 48 is connected to the drain tank 42 via the drain pipe 47b.

[0017] At the lower center of the oil tank 41, a rotating blade 50 for flowing engine oil is provided. A driven gear 54 is connected to the rotating blade 50 of the oil tank 41 via an output shaft 51, a clutch mechanism (power transmission mechanism) 52, and an input shaft 53. Further, a drive gear 56 is connected to the crankshaft 24 via a transmission shaft 55, and the drive gear 56 and the driven gear 54 are meshed with each other. In this way, the input shaft 53 is connected to the crankshaft 24 of the engine body 20 via the transmission shaft 55, the drive gear 56, and the driven gear 54, and the output shaft 51 is connected to the rotating blade 50 of the oil tank 41.

[0018] Next, the clutch mechanism 52 that transmits the rotational force of the crankshaft 24 to the rotating blade 50 will be described. FIG. 3A is a partial cross-sectional view showing an example of the clutch mechanism 52, and FIG. 3B is a cross-sectional view taken along line 3B-3B of FIG. 3A. Further, FIG. 4A is a partial cross-sectional view showing an example of the clutch mechanism 52, and FIG. 4B is a cross-sectional view taken along line 4B-4B of FIG. 4A. FIGS. 3A and 3B show the non-driving state of the clutch mechanism 52, and FIGS. 4A and 4B show the driving state of the clutch mechanism 52.

[0019] As shown in FIGS. 3A and 3B, the clutch mechanism 52 has a drum 60 that is connected to the output shaft 51 and is disposed radially outside the input shaft 53, and an annular rotating body 61 disposed between the input shaft 53 and the drum 60. The annular rotating body 61 of the clutch mechanism 52 has a plurality of clutch shoes (arc pieces) 62 arranged in the circumferential direction, and a plurality of springs 63 that connect the arc-shaped clutch shoes 62 to each other. Further, the clutch shoe 62 has an inner circumferential contact surface 62a facing the outer circumferential surface 53a of the input shaft 53 and an outer circumferential contact surface 62b facing the inner circumferential surface 60a of the drum 60. Furthermore, the clutch shoe 62 is movable between an inner position where the inner circumferential contact surface 62a contacts the outer circumferential surface 53a of the input shaft 53 and an outer position where the outer circumferential contact surface 62b contacts the inner circumferential surface 60a of the drum 60. The spring 63 provided on the annular rotating body 61 biases the clutch shoe 62 toward the inner position.

[0020] Such a clutch mechanism 52 can be activated in a driving state in which rotational force is transmitted from the input shaft 53 to the output shaft 51, and a non-driving state in which rotational force is not transmitted from the input shaft 53 to the output shaft 51. As shown in FIGS. 3A and 3B, the non-driving state of the clutch mechanism 52 is a state in which the clutch shoe 62 of the annular rotating body 61 is held at the inner position by the spring 63. In a situation where the rotational speed of the input shaft 53 is lower than a predetermined threshold value, since the centrifugal force of the clutch shoe 62 is lower than the biasing force of the spring 63, the clutch shoe 62 is held at the inner position where the inner peripheral contact surface 62a contacts the input shaft 53. Thus, in the non-driving state of the clutch mechanism 52, since the clutch shoe 62 of the annular rotating body 61 separates from the drum 60, rotational force is not transmitted from the input shaft 53 to the output shaft 51. Further, in the non-driving state of the clutch mechanism 52, since the clutch shoe 62 of the annular rotating body 61 contacts the input shaft 53, the annular rotating body 61 rotates so as to follow the input shaft 53.

[0021] As shown in FIGS. 4A and 4B, the driving state of the clutch mechanism 52 is a state in which the clutch shoe 62 of the annular rotating body 61 moves to the outer position by centrifugal force. In a situation where the rotational speed of the input shaft 53 exceeds a predetermined threshold value, since the rotational speed of the annular rotating body 61 increases and the centrifugal force of the clutch shoe 62 exceeds the biasing force of the spring 63, the clutch shoe 62 moves to the outer position where the outer peripheral contact surface 62b contacts the drum 60. Thus, in the driving state of the clutch mechanism 52, since the annular rotating body 61 contacts the drum 60 while rotating, rotational force is transmitted from the annular rotating body 61 to the output shaft 51 via the drum 60. Further, when the rotational speed of the annular rotating body 61 decreases due to contact with the drum 60, the clutch shoe 62 moves to the inner position as the centrifugal force decreases, so that the clutch mechanism 52 is switched from the driving state to the non-driving state again.

[0022] That is, when the rotational speed of the input shaft 53 exceeds a predetermined threshold value, the clutch mechanism 52 is alternately switched between a non-driven state and a driven state. As shown in FIG. 3B, when the clutch mechanism 52 is in the non-driven state, a rotational force is transmitted from the input shaft 53 to the annular rotating body 61 (arrow x1), and the rotational speed of the annular rotating body 61 gradually increases. Also, as the rotational speed of the annular rotating body 61 increases, the centrifugal force acting on the annular rotating body 61 also increases (arrow x2). When the centrifugal force acting on the annular rotating body 61 exceeds a predetermined value, as shown in FIG. 4B, the clutch mechanism 52 is switched to the driven state.

[0023] Further, when the clutch mechanism 52 is switched from the non-driven state to the driven state, a rotational force is transmitted from the annular rotating body 61 to the drum 60 (arrow y1), and the rotational speed of the annular rotating body 61 gradually decreases as the rotational force is transmitted. When the centrifugal force acting on the annular rotating body 61 falls below a predetermined value, the clutch shoe 62 begins to move inward (arrow y2) by the biasing force of the spring 63, and again, as shown in FIG. 3B, the clutch mechanism 52 is switched to the non-driven state. Thus, in a situation where the rotational speed of the input shaft 53 exceeds a predetermined threshold value, the clutch mechanism 52 repeatedly alternates between the non-driven state and the driven state.

[0024] Note that in order to determine the axial positions of the input shaft 53 and the clutch shoe 62, the clutch mechanism 52 is provided with a positioning mechanism (not shown). As this positioning mechanism, for example, it is conceivable to form a flange on the input shaft 53 and a receiving groove for receiving the flange on the clutch shoe 62. In this way, by receiving the flange of the input shaft 53 in the receiving groove of the clutch shoe 62, it is possible to regulate the axial position with the clutch shoe 62 while allowing radial movement of the clutch shoe 62.

[0025] <Control System> As shown in FIG. 2, the engine 10 has a control system 70 consisting of an electronic control unit 71 for controlling the engine body 20 and the water separation system 40. As sensors connected to the electronic control unit 71, there are an accelerator sensor 72 for detecting the operation amount of the accelerator pedal and a brake sensor 73 for detecting the operation amount of the brake pedal. Further, a start switch 74 for performing a start operation and a stop operation of the control system 70 is connected to the electronic control unit 71. Furthermore, as sensors connected to the electronic control unit 71, there are three level sensors 75 to 77 provided in the oil tank 41. A level sensor 75 is attached to the upper part of the oil tank 41, and level sensors 76 and 77 are attached to the lower part of the oil tank 41. Note that capacitance type level sensors are used as the level sensors 75 to 77.

[0026] FIG. 5 is a diagram showing an example of the basic structure of the electronic control unit 71. As shown in FIG. 5, the electronic control unit 71 has a microcontroller 82 in which a processor 80, a main memory (memory) 81, etc. are incorporated. A predetermined program is stored in the main memory 81, and the program is executed by the processor 80. The processor 80 and the main memory 81 are communicably connected to each other. Note that a plurality of processors 80 may be incorporated in the microcontroller 82, and a plurality of main memories 81 may be incorporated in the microcontroller 82.

[0027] The electronic control unit 71 also has an input circuit 83, a drive circuit 84, a communication circuit 85, an external memory 86, and a power supply circuit 87. The input circuit 83 converts signals input from various sensors into signals that can be input to the microcontroller 82. The drive circuit 84 generates drive signals for devices such as the electric oil pump 44 described above based on signals output from the microcontroller 82. The communication circuit 85 converts signals output from the microcontroller 82 into communication signals directed to other electronic control units 71 and the like. Also, the communication circuit 85 converts communication signals received from other electronic control units 71 and the like into signals that can be input to the microcontroller 82. Furthermore, the power supply circuit 87 supplies a stable power supply voltage to the microcontroller 82, the input circuit 83, the drive circuit 84, the communication circuit 85, the external memory 86, and the like. Also, programs and various data are stored in the external memory 86 composed of a non-volatile memory or the like.

[0028] <Rotation status of the rotating blades> The above-described water separation system 40 is a system that rotates the rotating blades 50 to flow the engine oil in the oil tank 41 in order to separate water from the engine oil in the oil tank 41. Hereinafter, the rotation status of the rotating blades 50 by the crankshaft 24 will be described. Here, FIG. 6 is a timing chart showing the rotation status of the crankshaft 24 and the rotating blades 50 and the operation status of the clutch mechanism 52. In FIG. 6, the drive state of the clutch mechanism 52 is shown as "ON", and the non-drive state of the clutch mechanism 52 is shown as "OFF".

[0029] As shown at time t1 in Fig. 5, when the engine speed Ne, which is the rotational speed of the crankshaft 24, is "0" (reference sign a1), that is, when the engine 10 is stopped, the clutch mechanism 52 operates in a non-driven state (reference sign b1). As shown at time t2, when cranking of the engine 10 by a starter motor (not shown) is started, the engine 10 is started and the engine 10 is controlled to an idling state (reference sign a2). Subsequently, as shown at time t3, when the engine speed Ne increases and exceeds a predetermined rotational speed N1 (reference sign a3), the clutch mechanism 52 is switched to a driven state (reference sign b2). That is, the situation where the engine speed Ne exceeds the predetermined rotational speed N1 is a situation where the rotational speed of the input shaft 53 interlocked with the crankshaft 24 exceeds a predetermined threshold value.

[0030] Then, when the clutch mechanism 52 is switched to the driven state (reference sign b2), since the rotational force is transmitted to the output shaft 51 via the clutch mechanism 52, the rotational speed of the rotating blades 50, which is the rotational blade speed Np, starts to increase (reference sign c1). Thereafter, since the clutch mechanism 52 is alternately switched between the non-driven state and the driven state (reference signs b3, b4), the rotational blade speed Np also gradually increases while fluctuating up and down (reference signs c2, c3). Thus, since the clutch mechanism 52 repeatedly alternates between the non-driven state and the driven state, the rotational blade speed Np will fluctuate up and down within a predetermined rotational speed range R1. That is, since the input shaft 53 and the output shaft 51 are not directly connected, even when the engine speed Ne fluctuates greatly, the rotational blade speed Np can be made to vary within the rotational speed range R1. Thereby, the rotating blades 50 can be rotated at a substantially constant speed by the crankshaft 24, and the engine oil 100 in the oil tank 41 can be gently flowed.

[0031] Here, FIG. 7 is a diagram showing the operating status of the water separation system 40 during engine operation. As shown in FIG. 7, the control system 70 holds the electric oil pump 44 in a stopped state, holds the return valve 46 in a blocked state, and holds the drain valve 48 in a blocked state during the period from when the driver turns on the start switch 74 until turning it off, that is, during the period from when the control system 70 performs the startup operation until performing the stop operation. That is, the control system 70 holds the electric oil pump 44 in a stopped state, holds the return valve 46 in a blocked state, and holds the drain valve 48 in a blocked state during the entire engine operation.

[0032] Accordingly, during the operation period of the engine 10, with the engine oil 100 stored in the oil tank 41, the rotary blades 50 can be rotated by the crankshaft 24, so that the engine oil 100 in the oil tank 41 can be made to flow. Also, as described above, since the clutch mechanism 52 that transmits the rotational force to the rotary blades 50 repeatedly alternates between the non-driven state and the driven state, the rotary blades 50 can be rotated at a substantially constant speed. Thereby, the engine oil 100 in the oil tank 41 can be stably made to flow, and water can be appropriately separated from the engine oil. As shown in FIG. 7, water 110 accumulates at the lower part of the oil tank 41, and engine oil 100 accumulates at the upper part of the oil tank 41.

[0033] <Oil replacement control> Next, oil replacement control for replacing the engine oil 100 in the oil tank 41 will be described. FIG. 8 is a flowchart showing an example of the execution procedure of the oil replacement control. Each step of the oil replacement control shown in FIG. 8 is a step executed by the processor 80 that constitutes the control system 70. Further, the oil replacement control is control executed by the control system 70 after the control system 70 is activated by the ON operation of the start switch 74 by the driver. Furthermore, the oil replacement control continues even after the start switch 74 is turned OFF by the driver and during the execution of the shutdown control for stopping various systems of the vehicle 11.

[0034] As shown in FIG. 8, the control system 70 proceeds to step S10 and determines whether the engine is running. If the control system 70 determines in step S10 that the engine is running, it proceeds to step S11 and determines whether the start switch 74 has been turned OFF by the driver. If the control system 70 determines in step S11 that the start switch 74 has been turned OFF, it proceeds to step S12 and determines whether the engine 10 has stopped due to fuel cut, ignition cut, etc.

[0035] If the control system 70 determines in step S12 that the engine 10 has stopped, it proceeds to step S13 and executes the water discharge mode. Here, FIG. 9 is a diagram showing an example of the execution status of the water discharge mode. As shown in FIG. 9, the control system 70 controls the electric oil pump 44 to the stopped state, the return valve 46 to the blocked state, and the drain valve 48 to the communicating state in order to execute the water discharge mode. As a result, as shown by the arrow FL1, the water 110 accumulated at the bottom of the oil tank 41 can be made to flow into the drain tank 42, and the water 110 separated from the engine oil 100 can be appropriately processed.

[0036] Further, the control system 70 continues to execute the water discharge mode based on the detection signals from the level sensors 76 and 77. That is, the control system 70 calculates the drainage rate in the water discharge mode using the detection signals from the level sensors 76 and 77, and controls the drain valve 48 based on this drainage rate so that the engine oil 100 does not flow into the drain tank 42. That is, when the lower level sensor 77 detects the boundary between the water 110 and the engine oil 100, the control system 70 controls the drain valve 48 to the shut-off state after a predetermined time calculated based on the drainage rate has elapsed. Thereby, only the water 110 separated from the engine oil 100 can flow into the drain tank 42, and a decrease in the engine oil 100 can be suppressed.

[0037] As shown in FIG. 8, when the control system 70 executes the water discharge mode in step S13, it proceeds to step S14 and executes the oil discharge mode. That is, the control system 70 executes the oil discharge mode after executing the water discharge mode. Here, FIG. 10 is a diagram showing an example of the execution status of the oil discharge mode. As shown in FIG. 10, in order to execute the oil discharge mode, the control system 70 controls the electric oil pump 44 to the stopped state, controls the return valve 46 to the communicating state, and controls the drain valve 48 to the shut-off state. Thereby, as shown by the arrow FL2, the engine oil 100 from which moisture has been separated can be returned from the oil tank 41 to the engine body 20. Further, the control system 70 continues to execute the oil discharge mode based on the detection signal from the level sensor 77. That is, when the lower level sensor 77 detects the oil level of the engine oil 100, the control system 70 controls the return valve 46 to the shut-off state after a predetermined time has elapsed. Thereby, all of the engine oil 100 stored in the oil tank 41 can be returned to the engine body 20.

[0038] As shown in FIG. 8, when the control system 70 executes the oil discharge mode in step S14, it proceeds to step S15 and executes the oil injection mode. That is, after executing the oil discharge mode, the control system 70 executes the oil injection mode. Here, FIG. 11 is a diagram showing an example of the execution status of the oil injection mode. As shown in FIG. 11, in order to execute the oil injection mode, the control system 70 controls the electric oil pump 44 to be in a driving state, controls the return valve 46 to be in a blocked state, and controls the drain valve 48 to be in a blocked state. Thereby, as indicated by the arrow FL3, the engine oil 100 stored in the oil pan 25 can be injected from the engine body 20 into the oil tank 41. Further, the control system 70 continues to execute the oil injection mode based on the detection signal from the level sensor 75. That is, when the control system 70 detects the oil level of the engine oil 100 by the upper level sensor 75, it controls the electric oil pump 44 to be in a stopped state after a predetermined time has elapsed. Thereby, an appropriate amount of engine oil 100 can be stored in the oil tank 41.

[0039] In this way, after the engine is stopped by the driver's start switch operation, that is, during the execution of the shutdown control by the control system 70, the water discharge mode, the oil discharge mode, and the oil injection mode are each executed. Thereby, the amount of engine oil in the engine body 20 does not excessively increase or decrease during engine operation, and it is possible to prevent oil shortage or excess during engine operation and protect the engine 10. Note that the water 110 stored in the drain tank 42 is periodically disposed of at a vehicle maintenance factory or the like.

[0040] <Other Embodiments> The present disclosure is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist thereof. For example, the illustrated engine 10 may be a gasoline engine using gasoline as fuel, a hydrogen engine using hydrogen as fuel, or a diesel engine using light oil as fuel. Further, the illustrated vehicle 11 is a vehicle equipped only with the engine 10 as a power source, but is not limited thereto, and may be a hybrid vehicle equipped with the engine 10 and a motor generator as power sources. Further, in the illustrated example, the clutch mechanism 52 including the annular rotating body 61 is used as the power transmission mechanism, but is not limited thereto. Any structure that repeats a driving state and a non-driving state may be used as the power transmission mechanism. For example, a friction clutch that is turned on and off by an electromagnet may be used.

[0041] In the illustrated example, two level sensors 76 and 77 are attached to the lower part of the oil tank 41, but the present invention is not limited thereto. Three or more level sensors may be attached to the lower part of the oil tank 41, or only one level sensor 77 may be attached to the lower part of the oil tank 41. Further, although a capacitance type level sensor is used as the level sensors 75 to 77, the present invention is not limited thereto. For example, as the upper level sensor 75, an electrode type or float type level sensor may be used. Further, as the lower level sensors 76 and 77, any type of sensor may be used as long as it can detect the boundary between the water 110 and the engine oil 100.

Explanation of Signs

[0042] 10… Engine, 20… Engine body, 24… Crankshaft, 41… Oil tank, 42… Drain tank, 43… Oil injection passage (first oil passage), 44… Electric oil pump (electric pump), 45… Return passage (second oil passage), 46… Return valve (first on-off valve), 47… Drain passage (drainage passage), 48… Drain valve (second on-off valve), 50… Rotating blade, 51… Output shaft, 52… Clutch mechanism (power transmission mechanism), 53… Input shaft, 60… Drum, 60a… Inner peripheral surface, 61… Annular rotating body, 62… Clutch shoe (arc piece), 62a… Inner peripheral contact surface, 62b… Outer peripheral contact surface, 63… Spring, 70… Control system, 80… Processor, 81… Main memory (memory), 100… Engine oil

Claims

1. An engine body having a crankshaft, An oil tank having rotating blades, A power transmission mechanism including an input shaft connected to the crankshaft and an output shaft connected to the rotating blades, A first oil passage connected to the engine body and the oil tank for supplying engine oil from the engine body to the oil tank, A second oil passage connected to the engine body and the oil tank for supplying engine oil from the oil tank to the engine body, And having, When the rotational speed of the input shaft exceeds a threshold value, the power transmission mechanism alternately repeats a driving state in which rotational force is transmitted from the input shaft to the output shaft and a non-driving state in which rotational force is not transmitted from the input shaft to the output shaft, Engine.

2. In the engine according to Claim 1, The power transmission mechanism, A drum disposed radially outside the input shaft and connected to the output shaft, An annular rotating body disposed between the input shaft and the drum and including a plurality of arc pieces arranged in the circumferential direction and a plurality of springs connecting the plurality of arc pieces to each other, And having, The plurality of arc pieces include an inner circumferential contact surface facing the outer circumferential surface of the input shaft and an outer circumferential contact surface facing the inner circumferential surface of the drum, The plurality of arc pieces are movable to an inner position where the inner circumferential contact surface contacts the outer circumferential surface and an outer position where the outer circumferential contact surface contacts the inner circumferential surface, The plurality of springs bias the plurality of arc pieces toward the inner position, Engine.

3. In the engine according to Claim 2, When the rotational speed of the input shaft exceeds the threshold value, the power transmission mechanism, A driving state in which the plurality of arc pieces move to the outer position due to an increase in the centrifugal force of the annular rotating body and rotational force is transmitted from the annular rotating body to the drum, A non-driving state in which the plurality of arc pieces move to the inner position due to a decrease in the centrifugal force of the annular rotating body and rotational force is not transmitted from the annular rotating body to the drum, And alternately repeats, Engine.

4. In the engine according to Claim 1, A drain tank connected to the oil tank via a drain passage, An electric pump provided in the first oil passage, A first on-off valve provided in the second oil passage, A second on-off valve provided in the drain passage, And a control system including a processor and a memory connected to be communicable with each other, And having, The control system holds the electric pump in a stopped state, holds the first on-off valve in a shut-off state, and holds the second on-off valve in a shut-off state during engine operation. Engine.

5. In the engine according to claim 4, the control system executes a water discharge mode in which, after the engine is stopped by the operation of the driver, the electric pump is controlled to a stopped state, the first on-off valve is controlled to a shut-off state, and the second on-off valve is controlled to a communicating state. After executing the water discharge mode, an oil discharge mode is executed in which the electric pump is controlled to a stopped state, the first on-off valve is controlled to a communicating state, and the second on-off valve is controlled to a shut-off state. After executing the oil discharge mode, an oil injection mode is executed in which the electric pump is controlled to a driving state, the first on-off valve is controlled to a shut-off state, and the second on-off valve is controlled to a shut-off state. Engine.

Images