A stroke translator or an injector having a solid-state actuator for generating a stroke and a hydraulic system for the hydraulic transmission of the stroke of the solid-state actuator to a control element such as a jet needle of a valve. The hydraulic system has hydraulic volumes hermetically sealed to the outside by metal bellows and constitute a hydraulic bearing with compensation for play. The advantages over known hydraulic levers are such that a complete metal seal is provided, and that a lower-wear design can be realized. Furthermore, a modular structure can be produced.