Abstract: The invention relates to measuring apparatus and its use, primarily for checking vehicle wheels, and more specifically the alignment of the rotational axes thereof. Two wheels, opposite each other on a vehicle, are provided with projecting stub axles which are disposed accurately coaxial with the respective wheel. The measuring apparatus comprises a scale unit (40) which is mounted on the axle of one of the wheels by means of a locating and fastening means (46, 48) so as to project at right angles therefrom and carrying a movable rider (50) with a scale (55), and a light beam unit (60) preferably comprising a laser (65) and disposed for mounting on the axle of the other wheel, by means of a locating and fastening means (66, 67), to send a light beam (33) onto the scale (55) carried by the movable rider (50) which is locked in an initial position.

Abstract: According to the invention, simple measuring apparatus (10) is produced which is designed to ascertain if a so-called spring strut (50) appertaining to the front wheel suspension in a vehicle has been deformed or more specifically if it has been bent, the apparatus being designed to be used primarily on wheels equipped with disc brakes. The apparatus is used in situ, i.e. on a spring strut (50) mounted in place in the vehicle, and it is necessary only for the wheel to be removed, with the tire and rim, so that the disc brake (40) is exposed. The measuring apparatus consists of an upright (12) which is attached to a base part (14, 20) designed to be attached, preferably by means of permanent magnets (24, 26), to the outside of the brake disc (40).

Abstract: An optical assembly is provided which comprises a light source, preferably a laser, and a particularly compensated prism unit, the laser and the prism unit being mounted on a common holder or base. The beam emitted from the laser is reflected 90.degree. by the prism unit, and although this unit is only approximately aligned with the laser the reflected beam will always form a right angle to the incident beam with an extreme accuracy, the deviation from 90.degree. being less than half an angular minute. The accuracy in reflexion independently of prism unit setting is attributed to the compensated prism unit, which comprises a quadrangular prism composed of two semi-quadrangular prisms, a reflecting surface being mounted, preferably in an adjustable position, adjacent one side of the prism.

Abstract: A measuring tool for checking frameworks, comprising a fixed part intended to be suspended between two opposing sides of the framework, and a movable part displaceable in or on the fixed portion. Both parts have longitudinal scales readable against indexes, variations in the distance between the sides of the framework being reflected on the scale of the fixed part which has graduations twice as large as those on the scale of the movable part. Graduations of the scales are so arranged that when the movable part is adjusted with its scale showing against its index the same value as that read on the scale of the fixed portion against its index, the movable portion will always assume the same position in relation to the centerline between the sides of the framework.

Abstract: An apparatus is provided for bringing a holder for an indicating member, e.g. a mirror, scale etc. component of measuring means, into exact coaxiality with a rotatable body, such as a vehicle wheel or wheel shaft, for checking the axis position and direction of the body. The apparatus comprises three main parts, viz. (a) a base member attachable to the body to be checked, (b) an intermediate member displaceable on the base member, and (c) said holder, which is tiltably carried on the intermediate member. Displacement of the intermediate member on the base member supplemented by tilting of the holder on the intermediate member readily brings the axis of the holder with its indicating member into accurate alignment with the axis of the body.