The invention relates to a multi-dimensional measuring machine for linear, spatially bent workpieces, for example pipelines or sheet-metal edges. At the outer end of a spatially movable, position-detecting measurement arm a spatially swivellable and likewise position-detecting sensor is fitted which can make contact with a specific point orthogonally to the contour characteristic of the object to be measured. In order to make contact in a non-touching manner and without force reactions on the workpiece, the sensor is designed as a multiple fork-type light barrier which can be guided over the linear object to be measured. The light beams of the different light barriers which are at an angle to each other but are located in a single plane have a defined diameter. When the light barriers are shaded by a specific fraction, a position detection is triggered and thus for a specific contour point of an object to be measured the position and direction of its tangent is determined. For a specific plane of cross-section of the object to be measured, the subsequent shading of the individual light barriers and their respective spatial position - they envelop as it were the cross-section - result in the tube diameter, the central point position of the tube cross-section, and a possible deviation from the circular form.

Multi-dimensional measuring machine

A noncontact measuring device has a generally L-shaped pivotable and rotatable probe (10) means to be disposed along a straight portion of an object (P). Another noncontact measuring device has a rotatable probe means with an inverted L-shape (100) to be disposed along a straight portion of an object (P). The probe of the former device (10) projects a beam of light, while that ofthe latter device (100) projects two beams of light (A,B). For either measuring device, when the beam or beams of light are being intercepted by the object (P), coordinates of a predetermined point of the probe means are read by a three-dimensional shape measuring apparatus to which the device is connected.

Noncontact measuring device for cylindrical, elongated objects bent into three-dimensional shapes

The invention discloses a method for detecting the curvature of an optical fibre preform. The method comprises the steps of: S1, suspending the optical fibre preform; S2, performing laser detection and data recording: taking four detection points of the optical fibre preform, detecting the various detection points by utilizing a laser, and recording coordinate data of the various detection pointsin a recording manner of a rectangular coordinate system through detection software; and S3, performing analog calculation: determining the tail handle analog centre line and the rod body analog centre line of the optical fibre preform, taking the included angle between the tail handle analog centre line and the rod body analog centre line as the curvature index of optical fibre preform, and calculating the included angle between the tail handle analog centre line and the rod body analog centre line by utilizing a formula. The detection method in the invention can be suitable for large-scale production; the laser and the detection software are adopted for detection and data recording; the labour cost can be greatly reduced; the detection efficiency and the detection precision are increased; furthermore, when detection is carried out, the optical fibre preform is in the suspension state, which is the same as the state while wiredrawing; and thus, the reliability of detection data is improved.

Method for detecting curvature of optical fibre preform

The invention relates to a transportable measuring device for the optical measurement of pipe bends, covering structural dimensions such as angle, bending radius and limb lengths. In order also to be able to measure relatively large pipe bends with high accuracy independently of position, the invention proposes a transportable measuring instrument which is characterised by two measuring rails (2, 3), which are to be arranged at a right angle on an arbitrary horizontal plane (1) on which the measurement object (6) rests, and of which each supports a direction-finding measuring head (4) that can be displaced on said measuring rails and can be rotated or pivoted horizontally and vertically, with the aid of which measuring head it is possible to lock onto measuring points (9) marked on the neutral line or over the core of the pipe bend (6) to be measured.

Kuemmerling Rolf Dr Ing

Papers

Transportable measuring device for the optical measurement of pipe bends