Patent application number | Description | Published |
20080217428 | INJECTOR - A pressurizing piston has a head section, which contacts an axial end face of a piezoelectric actuator to receive displacement of the actuator, and a piston wall section, which is formed in a cylindrical shape and can move in an axial direction in response to the movement of the head section. The head section and the piston wall section are combined such that relative displacement therebetween is possible in a radial direction. An outer sleeve slidably holding an outer periphery of the piston wall section restricts radial movement of the head section. When an expansion-contraction direction of the actuator inclines with respect to the axial direction, inclination of the piston wall section is inhibited by a radial deviation caused between the head section and the piston wall section. Thus, pinching of the piston wall section to the outer sleeve is inhibited. | 09-11-2008 |
20080217429 | Injector - An injector includes a nozzle hole, a needle, an actuator, a piston that is displaced in an axial direction according to extension or contraction of the actuator, an outer sleeve holding the piston slidably on its outer circumferential side and defining a pressure chamber expanded or shrunk according to displacement of the piston. When fuel pressure in the pressure chamber is increased upon extension of the actuator, the needle opens the nozzle hole. The injector further includes an inner sleeve slidably fitted around the needle and received in the pressure chamber, an urging device for urging the inner sleeve in the axial direction and for increasing or decreasing its urging force according to displacement of the piston, an engagement surface, and a fuel chamber. A gap between the fuel chamber and the pressure chamber is closed or opened when the inner sleeve annularly engages or disengages from the surface, respectively. | 09-11-2008 |
20080217440 | Injector - An injector has an inner sleeve between a needle pressure receiving face of a needle and a rear end face of a valve body. The inner sleeve is slidably fitted to an outer periphery of a middle shaft section of the needle. The inner sleeve receives a reaction force of a spring located between the inner sleeve and a pressurizing piston, so an axial tip end (edge section) of the inner sleeve is pressed against the rear end face to achieve close contact therebetween. Thus, a volume of a pressure chamber can be reduced, so a valve opening force for lifting the needle can be acquired efficiently. Accordingly, injection of a large flow rate can be performed by increasing a lift amount of the needle and also quick lifting of the needle can be performed. | 09-11-2008 |
20080217441 | Injector - An injector has a lift limiting member provided by a single plate member. The plate member has a stopper face, multiple hole sections, a flow passage hole, and a spring seat face. An axial end face of a needle head section of a needle contacts the stopper face when the needle lifts by a predetermined amount. Transmitting sections of a pressurizing piston are loosely inserted in the hole sections. High pressure fuel can pass through the flow passage hole. The spring seat face receives an end portion of a spring that biases the needle in a valve closing direction. The lift limiting member limits a valve opening lift position of the needle, so a stable injection quantity is obtained. Thus, a surface area of the single plate member can be used in multiple functions. | 09-11-2008 |
20080223960 | Fuel injection valve - A fuel injection valve includes a main body having a nozzle hole and a compression chamber. The main body accommodates a compression unit for pressurizing fuel accumulated in the compression chamber. The fuel injection valve further includes a valve element being axially movable in the main body. The valve element includes a valve portion and a pressure-receiving portion. The valve portion is movable in an opening direction to open the nozzle hole in response to pressure of fuel being pressurized by the compression unit and applied to the pressure-receiving portion. A regulating unit is provided in the compression chamber for regulating movement of the valve element with respect to the opening direction. | 09-18-2008 |
20080245891 | INJECTOR - In an injector, a first shaft portion of a needle is slidably supported by a first sleeves which is loosely received in a first internal chamber, and a second shaft portion of the needle is slidably supported in a body. Thereby, the first and second shaft portions are supported by the different members, and a relatively large clearance is formed on a radially outer side of the first sleeve. | 10-09-2008 |
20090179088 | FUEL INJECTION APPARATUS - An inflection point sensing arrangement of an electronic drive unit, which drives a fuel injection valve, senses an inflection point in a pressure-changing process of the pressure in the control chamber. A charging and discharging condition changing arrangement of the electronic drive unit changes a charging condition for charging of the electric current to a piezoelectric actuator of the fuel injection valve or a discharging condition for discharging of the electric current from the piezoelectric actuator upon sensing of the inflection point, which is sensed with the inflection point sensing arrangement. | 07-16-2009 |
20090242669 | REGULATING CHECK VALVE AND FUEL INJECTON VALVE HAVING THE SAME - A valve chamber is defined in a valve body of the regulating check valve. A first communicating hole and a second communicating hole communicate the valve chamber with a first flow passage and with a the second flow passage, respectively. A valve element is slidably installed in the valve chamber to seat on or lift away from a valve seat to close or open the first communicating hole. A pressure in the first flow passage urges the valve element away from the valve seat, and a pressure in the second flow passage urges the valve element toward the valve seat. The spring is interposed between the valve element and the valve body to urge the valve element away from the valve seat. | 10-01-2009 |
20090277978 | FUEL INJECTION DEVICE - A piston can reciprocate in a piston guide cylinder in an axial direction and has a cavity on a piezo driver side thereof. If the piezo driver is energized, a tip of a projecting section of a pushing member pushes a bottom wall of the piston defining the cavity. If fuel pressure of a pressure control chamber increases via a pressurization chamber and a communication passage due to pressurization by the piston, a needle moves in a valve-opening direction against a first compression coil spring. Since the piston has the cavity, a movable mass of the piston is reduced while securing axial length of a sliding section. Thus, fuel leak from the sliding section between the piston and the piston guide cylinder can be suppressed, and an inertial resistance caused in the piston can be reduced. | 11-12-2009 |
20100006676 | FUEL INJECTION APPARATUS - A needle is received in a nozzle body and is adapted to reciprocate relative to an injection hole to open and close the injection hole. A pressure chamber receives the fuel and exerts a pressure against the needle in an opening direction away from the injection hole upon increasing of the pressure of the fuel in the pressure chamber. A damper arrangement is actuated upon increasing of the pressure in the pressure chamber to alleviate a change in the pressure in the pressure chamber. A pressurizing piston reciprocates to increase and decrease the pressure of the fuel in the pressure chamber. | 01-14-2010 |