Dorma-baubeschlag Gmbh & Co. Kg

Giselher Sieg

Horst Tillmann

Horst Tillman

A door check wherein a housing is affixed to the pivotable panel and a guide rail is affixed to the frame of a door. The housing contains a shaft which is rigidly connected with one end of an arm the other end of which is slidably guided by the rail. The shaft carries a disc cam having two asymmetric sections one of which is tracked by a spring-biased follower surrounding an antifriction bearing and tending to return the panel to its closed position and the other of which is tracked by a roller on the piston of a damper which yieldably opposes the movement of the panel back to its closed position. The configuration of the two cam sections is selected with a view to allow for a reduction of the resistance which the follower offers to opening of the door shortly after the panel leaves its closed position as well as to ensure that the damper can operate independently of the follower and vice versa. The damper has a spring which urges the roller against the cam and whose bias is not more than 50 percent of the bias of one or more springs which urge the follower against the cam.

Door check

An automatic door closer whose housing confines a reciprocable damper piston cooperating with a rotary shaft to rotate the shaft in a direction to close the door or to be moved by the shaft in response to opening of the door. The piston can be biased in a direction to close the door through the medium of the shaft by a strong coil spring as well as by a relatively weak second spring in the form of a torsion spring, an extension spring or a compression spring. The second spring ensures that the party opening the door invariably encounters some resistance to movement of the door from closed position as well as that the door begins to move toward the closed position as soon as the door opening force is reduced below the force of the second spring. The first spring is acted upon by a stressing device to ensure that such spring cannot oppose movements of the door to open position but is available to close the door with a certain delay following a relaxation of the door opening force so that the first spring can assist the second spring in closing the door if the first spring cannot close the door alone.

Door closer

A door check wherein a housing is affixed to the pivotable panel and a guide rail is affixed to the frame of a door. The housing contains a shaft which is rigidly connected with one end of an arm the other end of which is slidably guided by the rail. The shaft carries a disc cam having two asymmetric sections one of which is tracked by a spring-biased follower tending to return the panel to its closed position and the other of which is tracked by the piston of a damper which yieldably opposes the movement of the panel back to its closed position. The configuration of the two cam sections is selected with a view to allow for a reduction of the resistance which the follower offers to opening of the door shortly after the panel leaves its closed position as well as to ensure that the damper can operate independently of the follower and vice versa.

In a door lock comprised of an elongated housing in which a piston loaded with a spring is displaceable in two opposite axial directions, a rotatable locking shaft connected to the door wing and provided with a pinion engaged with a rack formed on that piston, the spring is prestressed in the direction of the closing of the door. The spring acts on a displaceable supporting member which displaces the piston in the housing of the lock. An electromotor actuated by a control unit is operated to displace the supporting member.

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Ratingen, Germany

Giselher Sieg