Karl J Herrmann

US Patent:

49533240, Sep 4, 1990

Filed:

Mar 30, 1989

Appl. No.:

7/330828

Inventors:

Karl H. Herrmann - Seattle WA

Assignee:

Nova-Tech Engineering, Inc. - Edmonds WA

International Classification:

E05F 702

US Classification:

49255

Abstract:

A personnel door for sealing a room having a source of Radio Frequency (RF) radiation. The door when swung into a closed position can be energized to be partially disposed in an opening below floor level directly beneath the door. Sealing between the door and the door frame of the room can occur around the borders of the door including the part disposed in the opening below floor level. A step up into the room or use of a ramp to gain access to the room is thereby eliminated. In the preferred embodiment, the door is retained above the opening below floor level by springs and energized to move vertically downward into the opening against the force of the springs by an air cylinder.

US Patent:

40087832, Feb 22, 1977

Filed:

Jun 19, 1975

Appl. No.:

5/588421

Inventors:

Hans H. Herrmann - Seattle WA
Karl H. Herrmann - Seattle WA

Assignee:

CTEC Corporation - Bellevue WA

International Classification:

B62D 506

US Classification:

180140

Abstract:

A load transporting vehicle has a plurality of independently steerable wheel sets, each of which incorporates a turntable having a downwardly extending strut and a pivotally mounted trailing arm that carries a pair of wheels. The turntable is rotatably mounted on the vehicle frame. A pair of double acting piston and cylinder assemblies are coupled to rotate the turntable via a rack and pinion. A hydraulic control valve, having a control spool actuated by a boden type cable, controls the flow of hydraulic fluid to the piston and cylinder assemblies. The linear movement of the boden cable is programmed and controlled by rotatable cams. Three or four sets of cams, each set of which controls a different mode of steering, are mounted on a rotatable shaft. Each set of cams has a single cam to a given boden cable and associated wheel set. The sets of cams are interleaved to form groups corresponding to each wheel set.