Mechanicalarmsystemforopeningadoor.docx

1、MechanicalarmsystemforopeningadoorMechanical arm system for opening a doorBACKGROUND OF THE INVENTION1. Field of the InventionThe present invention relates to automatic door openers and other systems for opening or closing a door. More particularly, the present invention relates to a mechanical arm

2、system for opening a door, especially a Sensitive Compartmented Information Facility (SCIF) door, in which no component of the mechanical arm system is mounted on, or makes permanent contact with, the door.2. Background ArtAutomatic door openers, for many different applications, are well known in th

3、e art. Automatic door openers may be equipped on doors of public facilities to allow passage through the doorway of people without their manual operation. Automatic door openers may incorporate hydraulic, pneumatic, and electromechanical devices. For example, a conventional automatic door opener for

4、 opening or closing a door includes an a control unit, an actuator driving a drive shaft and an articulated opener arm extending between the drive shaft and the door. An end of the opener arm is either permanently mounted on one of the door or the door frame, with the actuator and drive shaft combin

5、ation mounted on the other of the door frame or the door. The opener arm responds to movement of the drive shaft to extend or contract so as to move the door to an open or closed position, respectively. The control unit may include adjustable timers and sensors to control the movement of the door, a

6、nd to identify when an obstacle is encountered in the doors pathway. Typically, the door opener must complete its opening process of placing the door in the open position before closure of the door can be initiated.Consequently, such a conventional door opener is unacceptable for use with a SCIF doo

7、r. The requirements for an SCIF door are dictated by the U.S. government, and two of these requirements provide that, except for the lock, key bypass, a door closer, and crash-put bar, nothing additional can be installed which makes permanent contact with the door and that the door must be able to r

8、eturn to its closed state, quickly, at any point in its forward opening cycle.What is needed, therefore, is a mechanism for automatically opening a door, in which none of the mechanisms components are mounted on the door itself, and further allows for closure of the door from any position during the

9、 door opening process. The present invention satisfies these and other needs, as will be made apparent by the description of the present invention that follows.BRIEF SUMMARY OF THE INVENTIONA mechanical arm system for opening a door is presented. In one embodiment, the system includes an actuator as

10、sembly having an output shaft and an arm driven by the output shaft for moving the door from a closed position to an open position. The actuator assembly is mounted to a support member adjacent the door, and the arm selectively contacts the door to move the door toward the open position. The arm is

11、moveable between a position in which the arm contacts the door in the open position and a retracted position in which the arm is free from contact with the door in the closed position. The door may be manually opened as well. The actuator assembly may be supported on a wall above the door.In one emb

12、odiment, the arm pivots in a first direction for contacting the door and a second direction for retracting from contact with the door, the arm pivoting with rotation of the output shaft. The actuator assembly may include a hydraulic rack and pinion rotary actuator having a piston that drives a rack

13、which meshes with a pinion, and the output shaft is coaxial with the pinion and rotates with rotation of the pinion. The mechanical arm system may include a controller unit, which activates and deactivates the hydraulic actuator and controls a rotational direction of the output shaft so as to pivot

14、the arm in the first direction or the second direction. The system may further include a hydraulic pump for supplying fluid to the hydraulic actuator, and the controller unit controls start and stop of the hydraulic pump so as activate and deactivate the hydraulic actuator, and controls the directio

15、n of fluid displacement by the pump so as to control the rotational direction of the output shaft. An open switch may be included for initiating movement of the door toward the open position under force of the arm. When the open switch has been activated, the controller unit controls the rotational

16、direction of the output shaft so as to pivot the arm in the first direction, whereby the arm contacts the door and moves the door toward the open position. A stop switch may be included for aborting movement of the door toward the open position under force of the arm. A pressure overload sensor may be included for sensing when the hydraulic pressure of fluid supplied to the hydraulic actuator rises above a pre-set limit. When the pre-set pressure limit h