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JP-2026074573-A - Hydrogen engine

JP2026074573AJP 2026074573 AJP2026074573 AJP 2026074573AJP-2026074573-A

Abstract

[Problem] In a hydrogen engine, when blow-by gas is configured to be discharged from the crankcase, the consumption of engine oil is reduced. [Solution] A discharge passage 40 connected to the crankcase 10 is provided. A separation device 4 connected to the discharge passage 40 is provided to separate engine oil E1 from the blow-by gas discharged from the crankcase 10 through the discharge passage 40 and return the separated engine oil E1 to the crankcase 10. The separation device 4 is attached to the outer surface of the cylinder 11 or the outer surface of the crankcase 10. [Selection Diagram] Figure 1

Inventors

  • 岸 真治
  • 白石 健太郎

Assignees

  • 株式会社クボタ

Dates

Publication Date
20260507
Application Date
20241021

Claims (9)

  1. A hydrogen engine that is supplied with hydrogen as fuel, The engine comprises a crankcase that stores engine oil and houses the crankshaft, a cylinder, a piston housed in the cylinder, and a connecting rod that connects the crankshaft and the piston. A discharge passage connected to the aforementioned crankcase, The system is equipped with a separation device connected to the aforementioned discharge passage, which separates the engine oil from the blow-by gas discharged from the crankcase through the aforementioned discharge passage and returns the separated engine oil to the crankcase. A hydrogen engine in which the separation device is attached to the outer surface of the cylinder or the outer surface of the crankcase.
  2. The hydrogen engine according to claim 1, wherein the separation device has a pump function for drawing the blow-by gas from the crankcase through the discharge passage.
  3. The separation device is equipped with a pressure sensor for detecting the pressure of the blow-by gas drawn into it. The hydrogen engine according to claim 2, wherein the separation device changes the amount of blow-by gas drawn in so that the detected value of the pressure sensor falls within a preset range.
  4. An intake passage is provided for supplying combustion air to the cylinder, The hydrogen engine according to claim 1, further comprising a recirculation passage for supplying the blow-by gas discharged from the separation device to the intake passage.
  5. The system includes a turbine that is driven to rotate by the exhaust gas supplied from the cylinder, and a supercharger that compresses the air in the intake passage with the turbine to supercharge the cylinder. The hydrogen engine according to claim 4, wherein the reduction passage is connected to a portion of the intake passage upstream of the supercharger.
  6. The hydrogen engine according to claim 4, further comprising a switching unit that can switch between a reduction state in which the blow-by gas discharged from the separation device is guided to the reduction passage, and a discharge state in which the blow-by gas discharged from the separation device is discharged.
  7. The separation device is equipped with a hydrogen concentration sensor for detecting the hydrogen concentration of the blow-by gas discharged from the separation device. The hydrogen engine according to claim 6, wherein the switching unit is operated based on the detected value of the hydrogen concentration sensor.
  8. A first air cleaner supplies outside air to the intake passage as clean combustion air, A first supply passage is provided, which extends from the portion of the intake passage closer to the first air cleaner than the portion to which the recirculation passage is connected, to the crankcase. The hydrogen engine according to claim 4, wherein the air from the intake passage is supplied to the crankcase via the first supply passage.
  9. A second supply passage connected to the crankcase, The system is equipped with a second air cleaner connected to the second supply passage, The hydrogen engine according to claim 8, wherein outside air is supplied through the second air cleaner to the second supply passage and supplied to the crankcase via the second supply passage.

Description

This invention relates to a hydrogen engine that uses hydrogen as fuel. In hydrogen engines, if unburned gases or fuel-air mixture (hereinafter referred to as blow-by gas) leak from the cylinder into the crankcase, hydrogen blow-by gas is more easily ignited than blow-by gas from gasoline or diesel fuel. Therefore, as disclosed in Patent Document 1, some engines are equipped with ventilation passages and ventilation fans to discharge blow-by gas from the crankcase. International public access number WO2021/161610A1 This diagram shows the overall configuration of the power unit.This diagram shows the operating status of the power unit.This diagram shows the overall configuration of the power unit in a first alternative embodiment of the invention.This figure shows the overall configuration of the power unit in a second alternative embodiment of the invention. (Overall configuration of the power unit) Figures 1 to 4 show a power unit having a hydrogen engine 1 supplied with hydrogen as fuel. In addition to the hydrogen engine 1, the power unit includes a motor generator 2, an E-turbo 3, and a separation device 4, etc. The power from the power unit drives the generator, pumps, etc. (Configuration of hydrogen engine 1) As shown in Figure 1, the hydrogen engine 1 has a crankcase 10, cylinders 11, cylinder head 12, etc., and is configured as an inline four-cylinder type. The crankshaft 13 is rotatably housed in the crankcase 10, and engine oil E1 is stored in the crankcase 10. Four cylinders 11 are provided at the top of the crankcase 10, and connecting rods 15 are connected to the pistons 14 located inside the cylinders 11 and the crankshaft 13. Intake ports 16 and exhaust ports 17, intake valves 18 and exhaust valves 19, and spark plugs 20 are provided in the cylinder head 12, corresponding to each of the cylinders 11. An intake manifold 24 is provided in the cylinder head 12 so as to connect across the four intake ports 16. An exhaust manifold 25 is provided in the cylinder head 12 so as to connect across the four exhaust ports 17. (Configuration related to motor generator 2) As shown in Figure 1, the first inverter 21 is provided with respect to the motor generator 2, and a battery 23 is provided. A motor-generator 2 is installed in the crankcase 10 of the hydrogen engine 1. In the hydrogen engine 1, a flywheel (not shown) is connected to the crankshaft 13, and the transmission gear (not shown) of the motor-generator 2 meshes with the gear portion on the outer circumference of the flywheel. The flywheel is capable of storing rotational energy and releasing the stored rotational energy. When the motor generator 2 operates as a motor, the DC power from the battery 23 is converted to AC power by the first inverter 21 and supplied to the motor generator 2, causing the motor generator 2 to operate as a motor. The power from the motor generator 2 is transmitted to the crankshaft 13 of the hydrogen engine 1 via the flywheel, and the power from the hydrogen engine 1 and the power from the motor generator 2 are combined and output from the crankshaft 13 of the hydrogen engine 1. This state represents the combined operation performed by the first inverter 21. When the motor generator 2 operates as a generator, power from the hydrogen engine 1 is transmitted to the motor generator 2 via the flywheel, driving the motor generator 2. The AC power generated by the motor generator 2 is converted to DC power by the first inverter 21 and charged into the battery 23. The above state represents the state in which the charging operation by the first inverter 21 has been performed. (Configuration of E-Turbo 3) As shown in Figure 1, the E-turbo 3 has a turbine 31 and a turbine motor 32. The turbine 31 has a compressor wheel 31a and a turbine wheel 31b, and the compressor wheel 31a and the turbine wheel 31b are connected so as to rotate together as a single unit. A first air cleaner 33 is provided. An intake passage 34 extends from the first air cleaner 33 and is connected to the compressor wheel 31a of the E-turbo 3. An intake passage 35 extends from the compressor wheel 31a of the E-turbo 3 and is connected to the intake manifold 24 of the hydrogen engine 1. A throttle 36 is provided in the intake passage 35. The exhaust passage 37 extends from the exhaust manifold 25 of the hydrogen engine 1 and is connected to the turbine wheel 31b of the E-turbo 3. The exhaust passage 38 extends from the turbine wheel 31b of the E-turbo 3. The turbine motor 32 is capable of rotating the turbine 31. A second inverter 22 is provided for the turbine motor 32. The DC power from the battery 23 is converted to AC power by the second inverter 22 and supplied to the turbine motor 32, causing the turbine motor 32 to operate. The above state represents the supercharging operation performed by the second inverter 22. The turbine wheel 31b (turbine 31) of the E-Turbo 3 is rotationally driven by the exhaust gas from the exhaust manifold 25 and exhaust passa