Abstract: A snap-on or screw type, tamper evident closure having first and second relatively moveable plastic parts (16, 18) which move from an initial position to a new limiting position when the closure is first opened, the new limiting position being visually distinguishable from the initial position to provide the tamper evidence. The two plastics parts are formed in mutually intimate association but have inter-engaging complimentary formations (22, 28, 40, 42) which become irreversibly disengaged on first opening of the closure.

Abstract: A method of forming a component having a metallic shell (12) and a plastics insert (34). The component is formed by placing the shell (12) inside the mould cavity of a mould assembly (10) which forms part of an injection moulding machine. Prior to injection of plastics material, part of the external surface of the shell (12) is spaced from the opposed surface of the mould cavity. The open end of the shell abuts the adjacent mould cavity and wall so as to form a seal. This end wall is frusto-conical in shape so that, during injection of plastics material, as the shell (12) is reformed by polymer pressure into complete engagement with the surface of the mould cavity, longitudinal contraction of the shell in response to this direct lateral strain is compensated for by the frusto-conical shape so that the seal is maintained.

Abstract: Semi-rigid washers are coaxially disposed to form an air-permeable spindle for coaxially supporting flexible record disks. A plurality of such washers and disks is coaxially stacked to construct a flexible disk file. Washers preferably have an annular shoulder with a depth slightly different than the thickness of the record disks for firmly supporting and aligning same in the coaxial stack. Alternatively, disks may be adhesively secured to a radial outward portion of each washer. Additionally, each washer has a plurality of radially extending air passageways for facilitating radial air movement which controls the stack of flexible record disks. A radial inward portion of each washer abuts each adjacent washer for forming a firm axial stack of disks. A rigid stabilizing plate at each axial end completes the assembly.

Abstract: A signal storage apparatus employs a stack of circular record disks accessible by axially separating segments of selected disks in the stack. One disk in a stack of coaxial rotatable circular compliant record disks is accessed with a minimum energy imparted to such disks by a chord roll disk separator. In a preferred form, the chord roll disk separator induces a primary bending mode to some of the disks being axially separated. In another aspect of the disclosure, a signal transducer is mounted integrally with the disk separator. With such mounting, primary, secondary, or higher order bending modes may be successfully employed. Full chordal and partial chordal axial disk separations are described. Arcuate and radially directed separation techniques may be employed. A unique axial stacking arrangement for compliant record disks is also described.