Abstract: Provided is an engine control device for controlling an opening degree of a valve adjusting a flow rate of an air-fuel mixture of an engine, wherein the opening degree is corrected based on an exhaust temperature deviation which is a deviation between a reference value and a current value of an exhaust temperature when controlling the opening degree.

Abstract: An upper revolving structure (4) of an electric hydraulic excavator (1) includes a revolving frame (7), an operator's seat (10), an electric motor (15), a hydraulic pump (17) driven by the electric motor (15), an oil tank (18), and an exterior cover (20) disposed in the revolving frame (7) to cover electrical equipment including the electric motor (15) and hydraulic equipment including the hydraulic pump (17) and the oil tank (18). A partitioning member (25) that is disposed in the revolving frame (7) to partition an inside of the exterior cover (20) into an electrical equipment room (28) and a hydraulic equipment room (29). An electrical equipment cooling device (31) including an electrical equipment cooling fan (34) is disposed in the electrical equipment room (28), and a hydraulic equipment cooling device (35) including a hydraulic equipment cooling fan (37) is disposed in the hydraulic equipment room (29).

Abstract: A precombustion chamber gas engine includes a main-chamber forming portion forming a main combustion chamber, and a precombustion-chamber forming portion forming a precombustion chamber communicating with the main combustion chamber via a plurality of nozzle holes. The precombustion-chamber forming portion includes a cylindrical portion extending along an extension direction of a precombustion chamber central axis of the precombustion-chamber forming portion, and a tip portion closing a main-combustion-chamber-side end of the cylindrical portion and having the nozzle holes. The tip portion includes a thin region having a thickness T satisfying T<L where L is a length of each nozzle hole.

Abstract: A precombustion chamber gas engine includes a main-chamber forming portion forming a main combustion chamber, and a precombustion-chamber forming portion forming a precombustion chamber communicating with the main combustion chamber via a plurality of nozzle holes. The precombustion-chamber forming portion includes a cylindrical portion extending along an extension direction of a precombustion chamber central axis of the precombustion-chamber forming portion, and a tip portion closing a main-combustion-chamber-side end of the cylindrical portion and having the nozzle holes. The tip portion includes a thin region having a thickness T satisfying T<L where L is a length of each nozzle hole.

Abstract: A precombustion chamber gas engine includes a main-chamber forming portion forming a main combustion chamber, a precombustion-chamber forming portion forming a precombustion chamber including a small-diameter cylinder chamber communicating with the main combustion chamber via a plurality of nozzle holes and a large-diameter cylinder chamber, an ignition device disposed in the large-diameter cylinder chamber of the precombustion chamber, and a precombustion-chamber-gas supply device for supplying a precombustion-chamber fuel gas to the precombustion chamber not via the main combustion chamber.

Abstract: A knocking detection method includes: a step of obtaining an oscillation waveform generated by combustion in the combustion chamber; a step of setting a first time window preceding a maximum inner pressure time at which an inner pressure of the combustion chamber is at maximum in a single combustion cycle and a second time window immediately after the maximum inner pressure time, and transforming each of a first waveform portion included in the first time window and a second waveform portion included in the second time window into an expression-domain expression, of the oscillation waveform; and a step of extracting a first peak at which amplitude of the frequency domain expression of the first waveform portion is at maximum in the first frequency windows and a second value at which the amplitude of the frequency domain region of the second waveform portion is at maximum in the second frequency window and determining whether knocking has occurred on the basis of the second peak value and the first peak value.

Abstract: A knocking detection method includes: a step of obtaining an oscillation waveform generated by combustion in the combustion chamber; a step of setting a first time window preceding a maximum inner pressure time at which an inner pressure of the combustion chamber is at maximum in a single combustion cycle and a second time window immediately after the maximum inner pressure time, and transforming each of a first waveform portion included in the first time window and a second waveform portion included in the second time window into an expression-domain expression, of the oscillation waveform; and a step of extracting a first peak at which amplitude of the frequency domain expression of the first waveform portion is at maximum in the first frequency windows and a second value at which the amplitude of the frequency domain region of the second waveform portion is at maximum in the second frequency window and determining whether knocking has occurred on the basis of the second peak value and the first peak value.

Abstract: A engine system is provided with: a plurality of cylinder groups which burn a gas mixture and discharge an exhaust gas; a plurality of high-pressure stage superchargers each having high-pressure stage turbines driven by the exhaust gas from the corresponding cylinder group and high-pressure stage compressors rotated by driving of the high-pressure stage turbines and configured to compress a gas supplied to the corresponding cylinder group; and a plurality of low-pressure stage superchargers having a low-pressure stage turbine driven by an exhaust gas discharged from the high-pressure stage turbine of the high-pressure supercharger which is any one of the plurality of high-pressure stage superchargers, and a low-pressure stage compressor rotated by driving of the low-pressure stage turbine and configured to compress a gas supplied to the high-pressure stage compressor of the high-pressure stage supercharger other than the one high-pressure stage supercharger.

Abstract: An internal combustion engine includes: an engine body (10) having at least one cylinder; and an air-supply manifold (4) including an adjustment pipe (12). The length of the adjustment pipe is set so that a first pressure wave (14A) propagating from the air-supply manifold toward the adjustment pipe and a second pressure wave (14B) propagating from the adjustment pipe toward the air-supply manifold have opposite phases from each other at the cylinder.

Abstract: An information processing apparatus according to an embodiment of the present disclosure includes a memory and a processor coupled to the memory. The processor is configured to acquire a drive state of a drive system that is provided with electronic devices, and control, based on the drive state of the drive system, program rewriting onto a target electronic device included in the electronic devices.

Abstract: A precombustion chamber gas engine includes a main-chamber forming portion forming a main combustion chamber, a precombustion-chamber forming portion forming a precombustion chamber including a small-diameter cylinder chamber communicating with the main combustion chamber via a plurality of nozzle holes and a large-diameter cylinder chamber, an ignition device disposed in the large-diameter cylinder chamber of the precombustion chamber, and a precombustion-chamber-gas supply device for supplying a precombustion-chamber fuel gas to the precombustion chamber not via the main combustion chamber.

Abstract: A precombustion-chamber engine includes a cylinder, a cylinder head disposed on a top of the cylinder, and a piston reciprocably disposed within the cylinder. A main combustion chamber is defined between the piston and the cylinder head. The cylinder head includes a precombustion-chamber forming part which defines a precombustion chamber communicating with the main combustion chamber through a nozzle. The precombustion chamber includes a cylindrical first passage part extending upwardly from the nozzle, a second passage part extending upwardly from the first passage part and having an upwardly-increasing cross-sectional area, and a cylindrical space part which extends upwardly from the second passage part and in which a spark plug is disposed. Center O of a cross-section, orthogonal to straight line L, of the second passage part is eccentric with respect to straight line L composed of an axis of the first passage part and an extended line of the axis.

Abstract: An internal combustion engine includes: an engine body (10) having at least one cylinder; and an air-supply manifold (4) including an adjustment pipe (12). The length of the adjustment pipe is set so that a first pressure wave (14A) propagating from the air-supply manifold toward the adjustment pipe and a second pressure wave (14B) propagating from the adjustment pipe toward the air-supply manifold have opposite phases from each other at the cylinder.

Abstract: An engine with an exhaust turbocharger includes: an exhaust bypass passage connected to an exhaust passage and bypassing a turbine of the exhaust turbocharger; a waste gate valve configured to open and close the exhaust bypass passage; a throttle valve disposed in an intake passage; a first pressure sensor and a second pressure sensor disposed upstream and downstream of the throttle valve in the intake passage; and a valve open-close control unit configured to calculate a pressure difference on the basis of pressure values detected by the first pressure sensor and the second pressure sensor, close the waste gate valve if the pressure difference is smaller than a threshold which is set in advance, and open the waste gate valve if the pressure difference is greater than the threshold.

Abstract: A gas engine includes a cylinder head, a prechamber cap that projects into a main combustion chamber by being inserted into an insertion hole formed in the cylinder head, that internally has a prechamber, and that supplies a flame generated in the prechamber to the main combustion chamber, and a prechamber holder that is disposed inside the cylinder head so as to hold the prechamber cap. One of the prechamber cap and the prechamber holder has a concave portion which accommodates an end portion of the other of the prechamber cap and the prechamber holder. An outer diameter of the end portion is set to be smaller than an inner diameter of the concave portion, thereby forming a space between the concave portion and the end portion at least in a radial direction orthogonal to a central axis.

Abstract: A precombustion-chamber engine includes a cylinder, a cylinder head disposed on a top of the cylinder, and a piston reciprocably disposed within the cylinder. A main combustion chamber is defined between the piston and the cylinder head. The cylinder head includes a precombustion-chamber forming part which defines a precombustion chamber communicating with the main combustion chamber through a nozzle. The precombustion chamber includes a cylindrical first passage part extending upwardly from the nozzle, a second passage part extending upwardly from the first passage part and having an upwardly-increasing cross-sectional area, and a cylindrical space part which extends upwardly from the second passage part and in which a spark plug is disposed. Center O of a cross-section, orthogonal to straight line L, of the second passage part is eccentric with respect to straight line L composed of an axis of the first passage part and an extended line of the axis.

Abstract: A engine system is provided with: a plurality of cylinder groups which burn a gas mixture and discharge an exhaust gas; a plurality of high-pressure stage superchargers each having high-pressure stage turbines driven by the exhaust gas from the corresponding cylinder group and high-pressure stage compressors rotated by driving of the high-pressure stage turbines and configured to compress a gas supplied to the corresponding cylinder group; and a plurality of low-pressure stage superchargers having a low-pressure stage turbine driven by an exhaust gas discharged from the high-pressure stage turbine of the high-pressure supercharger which is any one of the plurality of high-pressure stage superchargers, and a low-pressure stage compressor rotated by driving of the low-pressure stage turbine and configured to compress a gas supplied to the high-pressure stage compressor of the high-pressure stage supercharger other than the one high-pressure stage supercharger.

Abstract: An object is to improve a trap effect to trap ignition fuel gas supplied to a pre-combustion chamber and reduce an amount of non-combusted ignition fuel gas flowing out of the pre-combustion chamber to suppress a decrease in combustion efficiency. A pre-combustion-chamber type gas engine includes: a pre-combustion chamber Sr disposed on a cylinder head portion 10; a spark plug 20 disposed on an upper part of the pre-combustion chamber Sr; a pre-combustion-chamber gas supply mechanism configured to supply ignition fuel gas “g” to the pre-combustion chamber Sr via gas supply channels for the pre-combustion chamber 22a and 22b with an opening on an upper part of the pre-combustion chamber Sr; and a check valve 24 disposed in the gas supply channel 22b for the pre-combustion chamber.

Abstract: In an auxiliary chamber gas supplying device for a gas engine including an auxiliary chamber gas supply path (5, 14, 28, and 29) through which fuel gas is supplied to an auxiliary chamber (4), the auxiliary chamber gas supply path is connected to a fuel gas supply source (24) through a solenoid valve (23), and when the solenoid valve is opened, the fuel gas, in an amount corresponding to an opened period of the solenoid valve, is supplied from the fuel gas supply source to the auxiliary chamber through the auxiliary chamber gas supply path, and the opened period of the solenoid valve is set in such a manner that a predetermined amount of fuel gas is supplied to the auxiliary chamber, and a restriction unit (30) that extends the opened period of the solenoid valve is formed in the auxiliary chamber gas supply path (5, 14, 28, and 29).

Abstract: A gas engine includes a cylinder head, a prechamber cap that projects into a main combustion chamber by being inserted into an insertion hole formed in the cylinder head, that internally has a prechamber, and that supplies a flame generated in the prechamber to the main combustion chamber, and a prechamber holder that is disposed inside the cylinder head so as to hold the prechamber cap. One of the prechamber cap and the prechamber holder has a concave portion which accommodates an end portion of the other of the prechamber cap and the prechamber holder. An outer diameter of the end portion is set to be smaller than an inner diameter of the concave portion, thereby forming a space between the concave portion and the end portion at least in a radial direction orthogonal to a central axis.