Abstract: A fluid injector has a housing, an actuator unit and a valve body (2). The valve body (2) has a needle (22), which closes or opens a nozzle (213) depending on its position and comprises a guided zone (221). It further has a first part (21), which is arranged in a fixed position relative to the nozzle (213) and has a guided zone (215). It further has a second part (24), which has a first guide zone (242), that guides the guided zone (221) of the needle (22), and which has a second guide zone (243), that guides the guided zone (215) of the first part (21), with the second guide zone (242) having a greater diameter than the first guide zone (242).

Abstract: A fluid injector has a housing, an actuator and a valve body. The valve body has a cartridge (21) with a recess, that forms an injection nozzle on one end, and with a needle (22), that is arranged in the recess and closes the injection nozzle, if it rests with its seat area (224) on a needle seat (215) of the cartridge (21). The area (216) of the cartridge (21) adjacent to the needle seat (215) has a cylindrically-shaped outer contour and the needle (22) has a cylindrically-shaped area (223) adjacent to the seat area (224). The area (216) adjacent to the needle seat (215) and the cylindrically-shaped area (223) have the same diameter.

Abstract: A fluid injector has a housing, a valve body and an actuator unit inserted into the housing. The valve body has a cartridge with a recess that takes in a needle. The valve body further has a hollow body arranged in a fixed position to the needle and forming a first spring rest. The valve body further has a valve cap, which takes in the cartridge and forms a second spring rest. A return spring rests on the first spring rest and on the second spring rest. The valve cap, the housing and the cartridge are formed such, that before the valve cap and the housing and the valve cap and cartridge are permanently fixed to each other the valve cap is moveable relative to the housing and the cartridge while the housing and the cartridge stay in a fixed position relative to each other.

Abstract: The invention relates to a metering device for dosing pressurized fluids, comprising a housing with a metering opening, controlled an axially moveable valve needle, an axially extendable piezoelectric actuator, a thermal compensator unit, and an electrical connector for supplying electrical power to the piezoelectric actuator.

Abstract: An actuator unit has a tube spring (32), a piezoelectric actuator (31), that is inserted into the tube spring (32), a first cap (33), that is connected to the tube spring (32) at a first free end of the tube spring (32) and which is adjoined by the piezoelectric actuator (31), a tube-shaped body 38, that is connected to the tube spring (32) by joining and is arranged in the area of a second free end (35) of the tube spring (32), and a device for pretensioning, that is supported by the tube-shaped body (38) and pretensions the piezoelectric actuator (31). The actuator unit is simple and cheap to manufacture.