Patent ID: 7484777

Claim:
An electronic push retraction exit device for latching and unlatching a door, the exit device comprising: a support rail mountable to the door; a push rail mounted on the support rail and movable between an outward position and an inward position, the push rail being biased towards the outward position and movable to the inward position by manually pushing on an exterior surface of the push rail; a latch bolt operably connected to the push rail and movable between a latched position and an unlatched position, the push rail being connected to move the latch bolt to the unlatched position when the push rail is moved to the inward position; a linear actuator including a linearly movable shaft connected to move the push rail, the shaft including a splined section preventing the shaft from rotating and the linear actuator having a driving state, an off state and a holding state, wherein: the linear actuator moves the push rail towards the inward position when driven in the driving state, the linear actuator allows the push rail to return to the biased outward position when in the off state, and the linear actuator remains at a constant linear position and prevents the push rail from returning to the biased outward position when in the holding state; and a control circuit for controlling the linear actuator in the driving state, the holding state and the off state to move the push rail to the inward position, hold the push rail in the inward position and subsequently release the push rail to return to the outward position.