Abstract: A linear drive power door operator selectively and automatically opens and closes a door swingably mounted on a door jamb. The door operator includes a power screw disposed within a housing and a drive which powers the rotation of the power screw for moving a piston having a threaded bore threadably engaging the power screw linearly upon activation of the drive. A rack having teeth is engaged by the piston for moving the rack linearly from end-to-end. The power door operator further includes a pinion having teeth threadably engaging the teeth of the rack. The pinion is rotatable about a vertical axis upon the side-to-side linear movement of the rack. At least one link arm is pivotally connected at one of its ends to the pinion and pivotally connected at its other end to the door. A control device controls the operation of the drive for moving the door between a closed position and an open position.

Abstract: A door hold open device is disclosed for maintaining a door swingably mounted on a door jamb in an open position. The door hold open device includes an elongate track housing mounted on the door jamb, and a shaft disposed within the track housing. The shaft extends along a horizontal axis and is mounted for free rotation about the axis. A slider block having a threaded bore threadably engages a threaded portion of the shaft. The slider block is capable of moving linearly along the horizontal axis and causes the axial rotational movement of the shaft as it moves linearly from side-to-side. An arm link is pivotally connected at one of its ends to the slider block and pivotally connected at its other end to the door. The arrangement is such that upon manually opening and closing the door, the arm link moves the slider block linearly from side-to-side thereby causing the axial rotational movement of the shaft.

Abstract: A track driven power door operator selectively and automatically opens a door swingably mounted on a door frame. The power door operator includes an elongate track housing mounted on the door frame and a power screw disposed within the track housing. A drive is provided for powering the rotation of the power screw about the horizontal axis for moving a slider block linearly along the horizontal axis upon its activation. An arm link is pivotally connected at one of its ends to the slider block and pivotally connected at its other end to the door. A control is provided for controlling the operation of the motor for moving the slider block which rotates the door between its closed and open positions.

Abstract: A power actuated door operator for opening and closing a door has a power inlet into a cylindrical body containing a power piston, a hydraulic door closer piston with a rack gear for engaging with a pinion gear for operating a door control arm, a head separating the power piston in a chamber from the hydraulic door closer piston in a hydraulic chamber, a reciprocable rod extending through an opening in the head for transmitting pushing forces between the power piston and hydraulic door closer piston, and a spring for pushing the hydraulic piston to provide closing force to the door control arm after the door has been opened by the door operator, and further has the improvement providing capability for enabling the reciprocable rod to move radially with respect to faces of the power piston and the hydraulic closer piston to accommodate misalignments between the pistons, the rod, and the opening in the head.

Abstract: Disclosed is a door control device that automatically repositions the driving shaft of the door closer toward and away from the door pivot, as the door opens and closes, as a means of modifying and improving the force required to open and close the door. Movement is accomplished by a double ended driving shaft having a sprocket gear on one end which drivingly engages a track which in turn repositions the slide mounted door closer to more favorable positions as the door opens and closes.

Abstract: A swivel mounted armature plate for use with an electromagnetic door holder features a spherical socket connection to an adjusting screw which may be secured in any combination of depth and rotation within its operating range.