The present invention refers to a piston drive, in particular to a piston drive for actuating a valve or the like.
In general, piston drives are known which include a housing accommodating a suitably sealed reciprocating piston which includes a piston rod acting upon an operating device in dependence on the stroke of the piston. Conventional piston drives include various units such as an emergency actuation, stroke limitation as well as an end position control for the piston which units represent separate components cooperating with the piston rod of the piston drive and mounted to the housing usually at the axial ends thereof. Such an arrangement, however, renders it difficult to find space for connections to the operating device. Since the piston drive with the separate units for performing certain functions requires a relative large space for the installation, problems were frequently encountered because not enough installation space was available.
USPTO Backgrounds
USPTO Backgrounds