Abstract: A linear actuator has a housing with a bore extending therethrough. A first portion of the bore extends into the housing from a first end, and a second portion of the bore extends into the housing from a second end of the housing. The second portion of the bore has a rectangular geometry with substantially rounded corners when viewed from the second end. A shaft is in sliding engagement with the first portion of the housing. A piston member is coupled to the shaft and has a rectangular geometry with substantially rounded corners. The piston member is in sliding engagement with a first interior surface of the second portion of the bore via one or more o-rings. An anti-rotation apparatus is associated with one or more of the piston member and the shaft, wherein the anti-rotation member generally prevents a rotation of the shaft with respect to the housing.

Abstract: A linear actuator has a housing with a bore therethrough, thus defining an axis. A shaft is in sliding engagement with a portion of the bore and a piston is coupled to the shaft. An anti-rotation apparatus has an elongate slot defined in the housing which extends parallel to the axis. The elongate slot has opposing sidewalls that are non-parallel to one another and offset from a plane perpendicular to the axis by a respective predetermined angle ranging between zero and fifteen degrees. A bearing block has opposing sides and a hole therethrough, wherein an attachment member extends through the hole, coupling the bearing block to the shaft. The opposing sides of the bearing block are parallel to the respective opposing sidewalls of the elongate slot. The attachment member provides a selective engagement force between the opposing sides of the bearing block and the opposing sidewalls of the elongate slot.

Abstract: A linear actuator has a housing with a bore extending therethrough. A first portion of the bore extends into the housing from a first end, and a second portion of the bore extends into the housing from a second end of the housing. The second portion of the bore has a rectangular geometry with substantially rounded corners when viewed from the second end. A shaft is in sliding engagement with the first portion of the housing. A piston member is coupled to the shaft and has a rectangular geometry with substantially rounded corners. The piston member is in sliding engagement with a first interior surface of the second portion of the bore via one or more o-rings. An anti-rotation apparatus is associated with one or more of the piston member and the shaft, wherein the anti-rotation member generally prevents a rotation of the shaft with respect to the housing.