Abstract: A fuel property detection apparatus detects fuel properties based on cetane number and density of a tested fuel. Tested fuel is examined in terms of ignition timing, and, when the tested fuel has an ignition timing earlier than a threshold, the tested fuel is identified as having a standard cetane number. When the tested fuel has an ignition timing later than the threshold, the tested fuel is identified as having a low cetane number. An advance angle of the ignition timing is increased for yielding a greater ignition timing difference between a light property fuel and a heavy property fuel, and, in such manner, the difference therebetween is detected. When an advancement of the ignition timing is greater than a threshold, the fuel property is identified as heavy, and, when an advancement of the ignition timing is smaller than the threshold, the fuel property is identified as light.

Abstract: A fuel property detection apparatus detects fuel properties based on cetane number and density of a tested fuel. Tested fuel is examined in terms of ignition timing, and, when the tested fuel has an ignition timing earlier than a threshold, the tested fuel is identified as having a standard cetane number. When the tested fuel has an ignition timing later than the threshold, the tested fuel is identified as having a low cetane number. An advance angle of the ignition timing is increased for yielding a greater ignition timing difference between a light property fuel and a heavy property fuel, and, in such manner, the difference therebetween is detected. When an advancement of the ignition timing is greater than a threshold, the fuel property is identified as heavy, and, when an advancement of the ignition timing is smaller than the threshold, the fuel property is identified as light.

Abstract: A fuel injector injects high-pressure gaseous fuel directly into a cylinder of an engine. A small amount of liquid fuel is used in the injector to lubricate sliding portions of the fuel injector in addition to utilizing it as a medium for transmitting driving force. The fuel injector includes a nozzle member having injection holes at its elongated end and a needle slidably disposed in an elongated center hole of the nozzle member. The needle is driven by pressure of the liquid fuel introduced into a control chamber to open or close the injection holes. The pressure in the control chamber is controlled by a switching valve which is in turn driven by an actuator such as an electromagnetic or piezoelectric actuator. The liquid fuel is injected together with the high-pressure gaseous fuel after lubricating the sliding portions between the nozzle member and the needle.

Abstract: A fuel injector is configured to inject gaseous fuel into a combustion chamber of an engine by using liquid fuel as a pressure transmission medium to open and close a nozzle hole. A nozzle portion has a fuel chamber and a tip end, which defines the nozzle hole. A first passage is configured to communicate the fuel chamber with a gaseous fuel passage to introduce gaseous fuel. A second passage is configured to communicate the fuel chamber with a liquid fuel passage to introduce liquid fuel. A passage switching valve is configured to switch the first passage and the second passage.

Abstract: A fuel injector injects high-pressure gaseous fuel directly into a cylinder of an engine. A small amount of liquid fuel is used in the injector to lubricate sliding portions of the fuel injector in addition to utilizing it as a medium for transmitting driving force. The fuel injector includes a nozzle member having injection holes at its elongated end and a needle slidably disposed in an elongated center hole of the nozzle member. The needle is driven by pressure of the liquid fuel introduced into a control chamber to open or close the injection holes. The pressure in the control chamber is controlled by a switching valve which is in turn driven by an actuator such as an electromagnetic or piezoelectric actuator. The liquid fuel is injected together with the high-pressure gaseous fuel after lubricating the sliding portions between the nozzle member and the needle.

Abstract: A protective cover assembly of a gas sensor which is made up of an inner and an outer cover. The inner cover is disposed within the outer cover coaxially through a given clearance. The dimension of the clearance is defined within a range suitable for improving the response rate of the gas sensor while ensuring the effect of avoiding the damage such as cracks in a sensor element arising from wetting thereof with moisture contained in a measurement gas.

Abstract: A protective cover assembly of a gas sensor which is made up of an inner and an outer cover. The inner cover is disposed within the outer cover coaxially through a given clearance. The dimension of the clearance is defined within a range suitable for improving the response rate of the gas sensor while ensuring the effect of avoiding the damage such as cracks in a sensor element arising from wetting thereof with moisture contained in a measurement gas.