Abstract: A chain saw guide bar includes outer side surfaces, a longitudinal groove having side walls, and two edge surfaces. Each edge surface interconnects a side wall and an outer side surface to form therewith inner and outer corners, respectively. To edge-harden the guide bar, the edge surfaces, inner corners, and outer corners are heated above 750.degree. C. Then, the edge surfaces and inner corners are rapidly cooled, i.e, quenched, but the outer side surfaces are cooled more slowly, whereby the inner corners are given a higher hardness than the outer corners.

Abstract: A navigation system for detecting the position and controlling the movement of an automatically guided vehicle (1) comprises at least one light source (4) and at least one detector (5) responsive to the light emitted from the light source (4), the vehicle (1) be accompanied by either the light source (4) or the detector (5). A signal processing unit (10) has memory means (13) in which path control information (12) corresponding to the path (3) of the vehicle is stored, and comparator means (11) adapted to compare the path control information (12) stored in the memory means (13) with positional information produced by the system, in order, when the path control information and the positional information differ, to emit control signals (15) for the movement of the vehicle. The detector (5) is a position-sensitive semiconductor detector having a substantially planar, extended, continuous sensing area (7) and is adapted to receive light within a restricted part (P) of the sensing area of the detector.

Abstract: A robot installation for performing a plurality of assembling or machining operations at a work or assembly station comprises a robot with a rotatable tool support, e.g. a ring or disc, carrying a number of tools. The turning and positioning of the tool support are controlled by control equipment of the robot. The tools are adjustably positioned on the tool support.