DE19918348A1 - Positioning components with light beam triangulation sensor, involves determining measurement point distance from light source using reflection surface distance - Google Patents

Abstract

The method involves directing a light beam from a triangulation sensor (1) at a defined position onto a predetermined measurement point (MP) on the surface of a positioned component, detecting the reflected light to determine the distance from the measurement point to the light source, comparing this with a desired distance and correcting any error. A reflection surface (9) for the light beam is associated with the measurement point at a predetermined distance from the actual measurement point position and defined relative to the triangulation sensor. The measurement point distance is determined using the reflection surface distance. Independent claims are also included for the following: an arrangement for implementing the method.

Description

The invention relates to a method and a device for positioning components with the help of distance measurements with a light beam triangulation button, in particular of sheet metal components to be joined together in a joining station in the Automotive engineering.

It is known for the exact positioning of components to be connected to one another Use the light beam triangulation button. With these, the actual position of the components determined in a processing station, for example a welding station, and with one predetermined target position are compared. In the event of a deviation from the Manufacturing and position tolerances is a with the help of a control device Position correction made at least one component to the held To connect sheet metal components in the predetermined target position. The Distance measurement is carried out at predetermined measuring points of the respective component made, one of which is arranged in a predetermined measuring position Triangulation button emitted light beam directly to the respective measuring point on the Surface of the component directed and from this under one of the contour of the Component reflected at the measuring point and is detected by a sensor system. From the distance between the light beam source and the base point of the incident reflected beam becomes the actual distance of the measuring point from the triangulation probe certainly. This can lead to incorrect actual distance values and an incorrect one Position correction come when the contour of the sheet metal part in the area of respective measuring point deviates from the target contour and, for example, a dent, Has bulge or other deformation.

It is therefore an object of the invention to provide a method and a device for Positioning of components with a light beam triangulation button after To provide the preamble of claim 1, in which an influence of component  Contour deviations at a measuring point on the measurement result as far as possible is avoided.

This object is achieved in a method according to the preamble of claim 1 its characteristic features and solved with a device according to claim 3.

Thereafter, the invention is one in one in a predetermined Measuring position located light beam triangulation button sent out and on a predetermined measuring point on the surface of a positioned component reflected and detected by a sensor light beam for determination and subsequent correction of the actual distance of the respective measuring point from the Light beam source, wherein the determined actual distance with a predetermined target distance is compared, is not reflected directly from the measuring point, but from one of these upstream reflection surface. This is at a predetermined distance from the actual Position of the measuring point and at a predetermined angle to the Triangulation button is defined and is used by this instead of the measuring point targeted. The distance of the measuring point is thus the actual distance of the Reflection area determined by the triangulation button. Can be used as a triangulation button a laser beam triangulation button can be used.

With this procedure, a significant increase in the reliability of the Distance measurements between a positioned component and the triangulation button achieved because the light beam always at a defined ("ideal") reflection surface and is always reflected at the same angle. An incorrect measurement by the Influence of an actual contour deviating from the target contour of the component at the measuring point the reflection angle is therefore largely excluded.

A device for performing the method has a measuring block on which a reflection surface defined for the triangulation button for the light beam and one Contact surface are formed for the measuring point and the to the light beam Triangulation button is arranged relatively displaceable. The measuring block be advantageously mounted on a sled, it being expedient for reasons of space, arrange this slide so that the measuring block in the free space between the Component and the triangulation button in essentially the light beam direction and can be brought into contact with the measuring point in this direction.

The invention is described below using an exemplary embodiment. In the the accompanying drawing shows schematically:

Fig. 1 shows a device for positioning of components with a triangulation sensor,

Fig. 2 shows the device in a plan view,

Fig. 3 shows a component assignment for joining and

Fig. 4 shows the component assignment in a plan view.

The device shown in Fig. 1 has a laser beam triangulation button 1 with a sensor system for detecting a laser beam 2 emitted and reflected by it and a measuring block 3 , which are arranged in a joining station for position determination and correction of a component 4 in the horizontal. The measuring block 3 is fixed to a slide 5 and can be moved horizontally with it on a guide rail 6 in the area between the triangulation probe 1 and the component 4 .

FIG. 2 shows that the component 4 has a folded flange 7 on its side facing the triangulation button 1 for subsequent further processing. In the transition area to the folded flange 7 , a measuring point MP is predetermined on the component 4 for a horizontal position determination by measuring the distance of the component 4 from the triangulation button 1 . The measuring point MP is associated with the measuring block 3, which has an attachment surface 8 for this and on the the triangulation 1 side facing a defined the contact surface 8 and in their alignment with the triangulation 1 reflecting surface 9 of high surface quality of the emitted laser beam. 2 The contact surface 8 also bears against the measuring point MP if the angle of the folded flange 7 to the remaining component 4 deviates from the predetermined dimension ( 7 '). Fig. 2 also shows in dashed lines the target position of the component 4 with the corresponding position of the measuring block 3 with the parallel shifted reflection surface 9 and the laser beam 2 'reflected by this. From the deviation of the two reflected laser beams 2 and 2 ', the measure for the deviation of the component 4 from the horizontal desired position is determined and a correction of the actual position is initiated via a control unit (not shown).

FIGS. 3 and 4 show two to be joined plate members 10 and 11 are given for a rear door of a passenger car in a in the processing station actual position and in dashed lines the target position of the respective sheet metal part 10 and 11. Measuring points MP1 to MP4 are predetermined on the components. A triangulation button 1 is assigned to each measuring point. To adapt the actual position to the target position, the former is determined for each of the measuring points MP1 to MP4 according to the method described above, and if they deviate from the target position, a shifting of the sheet metal components 10 and 11 in via a control unit (not shown) causes the respective target position, the differences MP1-MP2 and MP3-IMP4 being the same as the mediation condition for the corrected actual positions.

REFERENCE SIGN LIST

1

Triangulation button

2nd

laser beam

3rd

Measuring block

4th

Component

5

carriage

6

Guide rail

7

Rebated flange

8th

Contact surface

9

Reflective surface

10th

Sheet metal component

11

Sheet metal component

Claims (5)

1. Method for positioning components with a light beam triangulation button, in which a light beam from the triangulation button located in a predetermined measuring position is directed to a predetermined measuring point on the surface of a positioned component, reflected and detected by a sensor system and with the reflected beam the actual distance of the measuring point is determined by the light source and compared with a specific target distance and corrected in the event of a deviation therefrom, characterized in that the measuring point (MP, MP1-MP4) is assigned a reflection surface ( 9 ) for the light beam which has a predetermined value Has a distance to the actual position of the measuring point (MP, MP1-MP4) and is defined in relation to the triangulation button ( 1 ), and that the actual distance of the measuring point (MP, MP1-MP4) is greater than the actual distance of the reflection surface ( 9 ) is determined. 2. The method according to claim 1, characterized in that a laser beam Triangulation button is used. 3. Device for carrying out the method for determining the position of a component in a processing station, with a light beam triangulation button with a sensor system for detecting the beam directed and reflected at a predetermined measuring point on the component according to claim 1 or 2, characterized in that it has a measuring block ( 3 ) with a reflection surface ( 9 ) defined for the triangulation button ( 1 ) for the light beam ( 2 ) and with a contact surface ( 8 ) designed for this for the measuring point (MP, MP1-MP4), which leads to the light beam triangulation button ( 1 ) is arranged to be relatively displaceable. 4. Device according to claim 3, characterized in that the measuring block a sled is supported and is arranged to be displaceable in a defined manner.   In that the measuring block (3) is 5. A device according to claim 4, characterized in that between the measuring point (MP, MP1-MP4) and said triangulation sensor (1) arranged to be displaceable substantially in the direction of light beam.