Abstract: This tape-type linear measuring instrument comprises a perforated tape adapted to be unwound from or wound on a drum enclosed in a case containing a tape-engaging toothed wheel possibly driven from a motor with the interposition of a speed reducer. Pick-up means responsive to reference marks carried by the wheel or by a member rigid therewith control the operation of an electronic up-and-down counter associated with means for the digital display of the measured length. A shifting pinion may be interposed between the winding drum and the tape-driving toothed wheel to enable the motor to drive the tape both ways. The perforations may be replaced by spaced notches, and a support wheel may be disposed under the tape in co-planar relationship with the driving wheel.

Abstract: The invention is concerned with a security key-ring meant in particular for prison turn-keys.It is composed of two half-shells, one male and one female, fitting together, that contain in the space between them an automatic roll-up mechanism with a strong recall spring in its rolled-up position, which mechanism pulls along a solid small chain sliding over the upper edge of the housing and reliably connected with a ring carrying the set of keys, having as a special feature that the rear face of the housing shows a metal fastening assembly in the shape of a clasp which holds it securely to the housing on a plane for its support.The invention can be expected to interest all key-ring manufacturers and those of small linear measuring instruments.

Abstract: A rigid linear measuring instrument has a central core moulded integrally with plastics bodies in relief. A plastic material of different colour is moulded over the core flush with outer faces of said bodies which form a series of graduation figures and graduation lines.