General Dynamics

About: General Dynamics is a company organization based out in Fairfax, Virginia, United States. It is known for research contribution in the topics: Signal & Propellant. The organization has 5722 authors who have published 5819 publications receiving 85768 citations. The organization is also known as: GD & General Dynamics Corporation.

Controlled elastomeric tooling for plastic fabrication

Abstract: Fiber reinforced thermoplastic resin composites are molded and cured in a system using controlled elastomeric tooling to apply molding pressure only after temperature has been increased to a selected point. A composite material to be molded and cured is typically placed between a fixed mold surface and a movable reaction block. A container is mounted on a fixed support behind the block in a manner permitting movement toward the block. The container has an interior base generally parallel to the block and an upstanding edge extending toward the block. A pad of an elastomeric material having a positive coefficient of thermal expansion is retained in the container by the edges. The pad extends beyond the edges into contact with the block. A gap of selected size lies between the pad and the container base. As the assembly is heated during molding, the pad expands into the gap without exerting significant pressure on the block. As heating continues, the gap becomes filled and the pad expands against the block exerting the selected molding pressure at the selected temperature. Adjustment means are provided permitting uniform molding pressures and pressure application temperatures over a large number of pads in complex mold assemblies despite variations in pad dimensions, age, etc.

Plunge milling tool

Abstract: A mill for deep removal of stock from a workpiece, such as machining pockets, wherein the mill cuts only in a Z direction. After reaching the desired depth, the mill is raised from the pocket and moved in an X or Y direction prior to plunging in for the next cut. A plurality of cutting blades is located on the face of the mill in such a way as to provide chip escape chambers up the inside of the mill, said chambers also serving to carry off the cutting fluid which is introduced to the pocket via a center bore in the mill, terminating at the face of the mill.

Method and system for hierarchical key access and recovery

Abstract: A key management system includes a hierarchy (10) of independent key arbitration centers (KAC) for providing access to a user's session keys through key management centers (KMC). When a court order is issued for a user's session keys, a message requesting the keys is transferred down through hierarchy until a terminal KAC (16, 36) is reached. Each KAC in the hierarchy adds its ID and signs (116) the message, verifying prior signatures (114). The user's ID is encrypted with the terminal KAC's public key. The terminal KAC engages in a blind key access procedure (129) with the KMC (18, 38) to receive the user's session key. The key is provided encrypted with the requesting party's or agency's public key. Accordingly, privacy is assured because only the KMC and the requesting agency have access to the actual key value, and only the terminal KAC and requesting agency have access to the user's ID. No other KACs in the hierarchy have access to the user ID or key value, and the KMC does not know which user's key has been provided.