An internal combustion engine, a method of operating the internal combustion engine, and a controller are disclosed. The method may comprise measuring a first pressure at a first position in a fluid line containing pressurized fluid; comparing the first pressure to a first threshold; in response to the first pressure exceeding the first threshold, transmitting a signal to depressurize the fluid line; after transmitting the signal to depressurize the fluid line, measuring a second pressure in the fluid line and comparing the second pressure to at least one of a second threshold and a third threshold, the second threshold being greater than the third threshold and less than the first threshold; and in response to the second pressure being less than the second threshold and exceeding the third threshold, transmitting another signal to depressurize the fluid line.

An internal combustion engine, a method of operating the internal combustion engine, and a controller are disclosed. The method may comprise measuring a first pressure at a first position in a fluid line containing pressurized fluid; comparing the first pressure to a first threshold; in response to the first pressure exceeding the first threshold, transmitting a signal to depressurize the fluid line; after transmitting the signal to depressurize the fluid line, measuring a second pressure in the fluid line and comparing the second pressure to at least one of a second threshold and a third threshold, the second threshold being greater than the third threshold and less than the first threshold; and in response to the second pressure being less than the second threshold and exceeding the third threshold, transmitting another signal to depressurize the fluid line.

A blow-by gas device of a supercharger-equipped engine includes a blow-by gas passage that introduces blow-by gas into an intake passage via a positive crankcase ventilation (PCV) valve. A supercharger has a supercharger rotor provided integrally with a rotation shaft rotatably supported on a bearing part. A space communicating with the bearing part is connected to a communication passage. The communication passage guides the blow-by gas into the space.

A blow-by gas device of a supercharger-equipped engine includes a blow-by gas passage that introduces blow-by gas into an intake passage via a positive crankcase ventilation (PCV) valve. A supercharger has a supercharger rotor provided integrally with a rotation shaft rotatably supported on a bearing part. A space communicating with the bearing part is connected to a communication passage. The communication passage guides the blow-by gas into the space.

A device for supplying lubricant for a fuel injection nozzle for injecting compressed natural gas (CNG) into an internal combustion engine is provided. The device includes a lubricant reservoir for supplying lubricant and having a feed pressure supply apparatus for applying a feed pressure to lubricant which is stored in the lubricant reservoir, where a feed pressure valve for setting the feed pressure is provided between the feed pressure supply apparatus and the lubricant reservoir, and a lubricant metering valve for metering the lubricant supply is provided between the lubricant reservoir and the fuel injection nozzle, where the lubricant is fed to the lubricant reservoir from an oil gallery of the internal combustion engine.

A device for supplying lubricant for a fuel injection nozzle for injecting compressed natural gas (CNG) into an internal combustion engine is provided. The device includes a lubricant reservoir for supplying lubricant and having a feed pressure supply apparatus for applying a feed pressure to lubricant which is stored in the lubricant reservoir, where a feed pressure valve for setting the feed pressure is provided between the feed pressure supply apparatus and the lubricant reservoir, and a lubricant metering valve for metering the lubricant supply is provided between the lubricant reservoir and the fuel injection nozzle, where the lubricant is fed to the lubricant reservoir from an oil gallery of the internal combustion engine.

A two-stage oil-injected screw air compressor includes an integrated compression casing, and the integrated compression casing further includes a first stage compression chamber, an intermediate cooling channel, and a second stage compression chamber parallel stacked in the integrated compression casing. A straightforward oil injector aims at the intermediate cooling channel to spray lubricating oil into the intermediate cooling channel.

A two-stage oil-injected screw air compressor includes an integrated compression casing, and the integrated compression casing further includes a first stage compression chamber, an intermediate cooling channel, and a second stage compression chamber parallel stacked in the integrated compression casing. A straightforward oil injector aims at the intermediate cooling channel to spray lubricating oil into the intermediate cooling channel.

The invention relates to a lubricating system for an internal combustion engine (1). The system includes a first conduit means (7) connecting a lubricant supply source (5) to the internal combustion engine (1) for supplying lubricant to the internal combustion engine (1). According to the invention, the system further includes a second conduit means (8) connecting a gas supply source to the first conduit means (7) for supplying gas to the first conduit means such that gas bubbles are formed in the first conduit means (7). A sensor (3) detects whether lubricant or whether gas is present in a certain part of the first conduit (7). The certain part being located downstream the connection of the second conduit means (8) to the first conduit means (7). A control unit (6) is connected to the sensor (3), which control unit (6) is arranged to determine whether lubricant is flowing through the first conduit means (7) or not, in response to the detections of the sensor (3). The invention also relates to an internal combustion engine, to a power tool and to a method for providing lubricant to an internal combustion engine.

The invention relates to a lubricating system for an internal combustion engine (1). The system includes a first conduit means (7) connecting a lubricant supply source (5) to the internal combustion engine (1) for supplying lubricant to the internal combustion engine (1). According to the invention, the system further includes a second conduit means (8) connecting a gas supply source to the first conduit means (7) for supplying gas to the first conduit means such that gas bubbles are formed in the first conduit means (7). A sensor (3) detects whether lubricant or whether gas is present in a certain part of the first conduit (7). The certain part being located downstream the connection of the second conduit means (8) to the first conduit means (7). A control unit (6) is connected to the sensor (3), which control unit (6) is arranged to determine whether lubricant is flowing through the first conduit means (7) or not, in response to the detections of the sensor (3). The invention also relates to an internal combustion engine, to a power tool and to a method for providing lubricant to an internal combustion engine.