Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
METHOD OF CONTACTLESS DETERMINATION OF GEOMETRIC ACCURACY OF THE SHAPE OF A TRANSPARENT SHAPED FLAT PRODUCT MADE OF GLASS OR PLASTICS AND A DEVICE FOR PERFORMING THE METHOD
Document Type and Number:
WIPO Patent Application WO/2021/175349
Kind Code:
A1
Abstract:
The invention relates to a method of contactless determination of geometric accuracy of the shape of a transparent shaped flat product (6) made of glass or plastics. The transparent shaped flat product (6) to be measured is placed in a predetermined measurement position on a measurement surface (31) of a measuring table (3), against which a measuring head (12) is arranged, fitted with a plurality of contactless measuring probes (11) which are arranged against the measurement surface (31) of the measuring table, whereby the measuring head (12) and the measurement surface (31) of the measuring table (3) move relative to each other during the measurement, whereby the distance between the contactless probes (11) and the measurement surface (31) of the measuring table (3) is constant and in predetermined positions of the contactless measuring probes (11) during the relative movement of the measuring head (12) and the measurement surface (31) of the measuring table (3), the distance of the contactless measuring probes (11) from the surface of the measured transparent shaped flat product (6) is evaluated, whereupon these distance values are compared with the desired distance values in positions corresponding to the measurement positions. The invention also relates to a device for performing the above- mentioned method.

Inventors:
HORAK MARCEL (CZ)
NOVOTNY FRANTISEK (CZ)
STARY MICHAL (CZ)
VRATNY JAN (CZ)
VRATNY MIROSLAV (CZ)
Application Number:
PCT/CZ2021/050027
Publication Date:
September 10, 2021
Filing Date:
March 03, 2021
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
FOR G S R O (CZ)
UNIV V LIBERCI TECCH (CZ)
International Classes:
G01B21/20; G01B5/00; G01B11/30; G01B17/06; G01B17/08; G01N21/958
Domestic Patent References:
WO2013034812A12013-03-14
WO2005022127A22005-03-10
Foreign References:
JP2008139268A2008-06-19
CN202383388U2012-08-15
US20070028681A12007-02-08
CN106840003A2017-06-13
Attorney, Agent or Firm:
MUSIL, Dobroslav (CZ)
Download PDF:
Claims:
PATENT CLAIMS

1. A method of contactless determination of geometric accuracy of the shape of a transparent shaped flat product (6) made of glass or plastics, characterized in that the transparent shaped flat product (6) to be measured is placed in a predetermined measurement position on a measurement surface (31) of a measuring table (3), against which a measuring head (12) is arranged, fitted with a plurality of contactless measuring probes (11) which are arranged against the measurement surface (31) of the measuring table, whereby the measuring head (12) and the measurement surface (31) of the measuring table (3) move relative to each other during the measurement, whereby the distance between the contactless probes (11) and the measurement surface (31) of the measuring table (3) is constant and in predetermined positions of the contactless measuring probes (11) during the relative movement of the measuring head (12) and the measurement surface (31) of the measuring table (3), the distance of the contactless measuring probes (11) from the surface of the measured transparent shaped flat product (6) is evaluated, whereupon these distance values are compared with the desired distance values in positions corresponding to the measurement positions. 2. The method according to claim 1 , characterized in that the measured values of the distances of the measuring probes (11) from the surface of the measured product (6) are compared with the values of the distances at the corresponding points of the CAD model of the measured product (6).

3. The method according to claim 1 or 2, characterized in that the relative movement of the measuring head (12) and the measurement surface

(31) of the measuring table (3) is caused by the movement of the measuring head (12).

4. The method according to any of the preceding claims, characterized in that the relative movement (12) and the measurement surface (31) of the measuring table (3) is caused by the movement of the measurement surface (31 ) or by the movement of the measuring table (3).

5. The method according to any of the preceding claims, characterized in that in the rest position of the measuring head (12), the distance of the measuring probes (11) with respect to the measurement surface (31) of the measuring table is adjusted (3) according to the assumed shape of the measured product (6) either individually or in groups to achieve the maximum accuracy of measurement. 6. The method according to any of the preceding claims, characterized in that the measured shaped product (6) on the measurement surface (31) of the measuring table (3) is placed in the horizontal position of the measuring table (3).

7. The method according to claim 6, characterized in that the measuring table (3) remains in the horizontal position during the measurement.

8. The method according to claim 6, characterized in that the measuring table (3) is turned to the horizontal position before starting the measurement.

9. The method according to any of the preceding claims, characterized in that before placing the measured shaped product (6) on the measurement surface (31) of the measuring table (3), supports (4) are distributed on the measurement surface (31) of the measuring table (3) for point contact with the measured product (6) and backstops (5) on the measurement surface (31) of the measuring table (3) are distributed to define the position of the measured product (6) on the measurement surface (31 ) of the measuring table (3).

10. The method according to claim 9, characterized in that the supports (4) and the backstops (5) are located on magnetic clamps (15), which are placed manually on the measurement surface (31) of the measuring table (3) in the direction of the x, y coordinates to a predetermined position of the measurement points, whereby the position is set by means of a laser beam perpendicular to the plane of the measurement surface (31) of the measuring table (3), whereby the heights of the supports (4) are adjusted individually according to the shape of the measured product (6) to the size of the z coordinate of the respective measurement point. 11. The method according to claim 9, characterized in that the supports

(4) and the backstops (5) are located on the magnetic clamps (15), which are distributed on the measurement surface (31) of the measuring table (3) in the direction of the x, y coordinates by means of a distributor (13) to a predetermined position of the measurement points, whereby the heights of the supports (4) are adjusted individually according to the shape of the measured shaped product (6) to the size of the z coordinate of the respective measurement point either before placing or after placing the supports (4) in the respective x, y coordinates.

12. The method according to claim 9, characterized in that the supports (4) and backstops (5) are fixedly mounted at the measurement points on a plate of a pseudo-scale model (18) which is placed on the measuring table (3) on fixing mandrels (19) which define its position.

13. The method according to any of the preceding claims, characterized in that the contactless measuring probes (11) are formed by confocal probes which emit beams of white light towards the surface of the measured product (6) and follow the beam reflected from the surface of the measured product (6) and evaluate the wavelength of the received beam from which they determine the distance from the surface of the measured product (6).

14. The method according to any of claims 1 to 12, characterized in that the contactless measuring probes (11) are formed by ultrasound probes.

15. A device for performing the method according to any of the preceding claims comprising a measuring table (3) with a measurement surface (31) for placing the measured transparent shaped flat product (6) made of glass or plastics, characterized in that arranged against the measurement surface (31) of the measuring table (3) is a measuring head (12) fitted with a plurality of contactless measuring probes (11) directed to the measurement surface (31) of the measuring table (3), whereby the measuring head (12) and the measurement surface (31) of the measuring table (3) are arranged with an option of relative movement during which the distance between the contactless probes (11) and the measurement surface (31) of the measuring table (3) remains constant, whereby the contactless measuring probes (11) are connected|/coupled to a control unit which is provided with evaluating means of the distance (z) of the contactless measuring probes (11) from the upper surface of the measured shaped product (6) in the respective coordinates (x, y). 16. The device according claim 15, characterized in that the measuring table (3) is formed by a measuring conveyor (32) with a movable measurement surface (31), on which the shaped products (6) to be measured are placed, whereby the measuring head (12) is stationary and is fixedly mounted on the frame (320) of the measuring conveyor (32) and extends across the entire width of the measuring conveyor (32).

17. The device according to claim 16, characterized in that the measuring conveyor (32) is part of the production line of the measured shaped products (6). 18. The device according to any of claims 15 to 17, characterized in that the contactless measuring probes (11) are arranged in the measuring head (12) in at least one row perpendicular to the direction of the relative movement of the measuring head (12) and the measuring table (3).

19. The device according to any of claims 15 to 18, characterized in that the contactless measuring probes (11) are mounted in the measuring head

(12) displaceably in the direction towards and away from the measurement surface (31) of the measuring table (3).

20. The device according to any of claims 15 and 18 to 19, characterized in that the measuring head (12) is mounted displaceably in the measuring plane in the direction perpendicular to the direction of the relative movement of the measuring head (12) and the measuring table (3).

21. The device according to any of claims 15 to 20, characterized in that the measuring head (12) it is provided at the ends with tilting arms (10) in which also contactless measuring probes (11) are accommodated. 22. The device according to any of claims 15 to 21 , characterized in that the contactless measuring probes (11) are formed by confocal probes or ultrasound probes.

23. The device according to any of claims 15 to 22, characterized in that the measuring table (3) is rotatably mounted on a frame (1), its measurement surface (31) being able to occupy a horizontal and measurement position. 24. The device according to any of claims 15 to 23, characterized in that on the measurement surface (31) of the measuring table (3), supports (4) and backstops (5) are mounted for point contact with the measured product (6) to define the position of the measured product (6) on the measurement surface (31 ) of the measuring table (3).

25. The device according to claim 24, characterized in that the supports (4) and the backstops (5) are mounted on magnetic clamps (15) displaceably with respect to the measurement surface (31) and are adjustable in the determined position on the measurement surface (31) of the measuring table (3).

26. The device according to claim 24, characterized in that the supports (4) and the backstops (5) are fixedly mounted at the measurement points on the plate/body of the pseudo-scale model (18) which can be fastened on the measurement surface (31) of the measuring table (3) by means of the fixing mandrels (19) which define its position.

Description:
Method of contactless determination of geometric accuracy of the shape of a transparent shaped flat product made of glass or plastics and a device for performing the method Technical field

The invention relates to a method of contactless determination of geometric accuracy of the shape of a transparent shaped flat product made of glass or plastics.

In addition, the invention relates to a device for performing the above- mentioned method, which comprises a measuring table with a measurement area for placing the measured transparent shaped flat product made of glass or plastics.

Background art At present, determination of the geometric accuracy of the shape of shaped glass, especially automotive glass, is performed in a contact manner on scale models, for example according to CN101749992, CN201926435, CN201964850, CN202216627 or CN208075720. A model equipped with several tens of contact sensors on the front side represents a partial 3D model of glass. The measured glass is placed on the model at RPS points and the position in the plane of the glass is determined by backstops. The glass is placed in the scale model on the RPS points between the backstops in an approximately horizontal position. The glass together with the scale model is then tilted by turning against the horizontal axis to a measurement position, the inclination of which to the horizontal plane corresponds to the position of the glass mounted on the car body (the so-called "car position"). The exact position of the glass is given by the glass resting on the backstops, to which it is pressed by gravity. At a single moment, all contact sensors are pushed into contact with the measured glass by a slight force, their position is recorded and compared with the coordinates corresponding to the 3D model. Coordinate differences must not exceed a predetermined value at the measured points. The disadvantage of measuring in a contact manner is the danger of glass deformation after its contact with the sensor and the resulting inaccuracy of the measurement. This is especially dangerous for very thin automotive glass currently produced. Another disadvantage is the need to have a unique scale model for each shape of glass.

CN109084682 tries to solve this problem by contactless determination of geometric accuracy of the shape of products of glass, especially automotive glass, by means of two measuring sets with laser probes. The first measuring set comprises a point laser probe which can obtain coordinates of a certain point on the outer surface of automotive glass by scanning. The second measuring set comprises a line laser probe which can obtain coordinates of points of the black edge of automotive glass. When coordinates are obtained, they are compared with a standard sample.

The disadvantage of using laser sensors (point and line laser sensors) for shape rugged surfaces is the inaccuracy of triangulation position measurement with a variable dependence of the measured value on the deviation of the transmitted beam from the measured surface normal. This disadvantage is even more pronounced for the case of sensing a glossy surface with a high degree of parasitic reflections. Another drawback is a reduced robustness of the sensor, associated with a high sensitivity to fluctuations in the exposure parameters of the sensed scene.

The object of the invention is therefore to eliminate the above-mentioned disadvantages and provide a contactless method of determination of geometric accuracy of the shape of transparent shaped flat products made of glass or plastics, especially automotive glass, and a device for implementing it.

Principle of the invention

The object of the invention is achieved by a method of contactless determination of geometric accuracy of the shape of a transparent shaped flat product made of glass or plastics, whose principle consists in that the shaped flat product to be measured is placed in a pre-determined measurement position on the measurement surface of a measuring table, against which is arranged a measuring head fitted with a plurality of contactless measuring probes, which are arranged against the measurement surface of the measuring table, whereby during the measurement, the measuring head and the measuring table move relative to each other, whereby the distance between the measuring probes and the measurement surface of the measuring table is constant and during the relative movement of the measuring head and the measuring table, the distance of the measuring probes from the surface of the measured transparent shaped flat product is evaluated in pre-determined measurement positions of the contactless measuring probes, whereupon these distance values are compared with the desired values corresponding to the measurement positions, for example, they are compared with the distance values at the corresponding points of the CAD model of the measured shaped product.

The advantage of this method is, in addition to eliminating the drawbacks of the background art, accurate measurement of geometric accuracy of the shape of thin automotive glass, easy handling of the measured glass and omission of models of different shapes and sizes of glass, which reduces measurement costs. Moreover, in this way it is also possible to measure geometric accuracy of the shape of other transparent shaped flat products made of glass or plastics, for example in architectural applications in building cladding, in solutions to the interior design of buildings, flats and in sanitary applications.

Another advantage is high flexibility and variability of the method of measurement when changing the controlled range of measured products, as well as high speed of measurement, while ensuring a much larger number of measured points compared with the current method of measurement. The measured product is not loaded by contact deformations from contact sensors and its position in space can be easily modified.

The relative movement of the measuring head and the measuring table is caused by the movement of the measuring head, or by the movement of the measuring table, or by the movement of both against each other.

In a preferred embodiment, bodies of the measuring probes in the rest position of the measuring head can move in the measuring head with respect to the measurement surface of the measuring table according to the assumed shape of the measured product either individually or in groups so as to achieve maximum measurement accuracy. This embodiment is suitable for more shaped products for which it is possible to achieve the optimal distance from the measured product by adjusting the measuring probes such that the values of the measuring distance are within the range of the highest measurement accuracy of the respective measuring probe.

In the basic embodiment, the product to be measured is placed on the measuring table which is in a horizontal position. The actual measurement then takes place either in this position, or the measuring table turns to a measurement position before starting the measurement. If the product to be measured is automotive glass, it is in the measurement position, the so-called car position, i.e., in the position in which it is placed in the car. In this manner, the deformations of the automotive glass depending on the direction of gravity are allowed for, thus avoiding problems in mounting the glass in the car, therefore the measurement position of the glass is defined by the car manufacturer.

For placement of the shaped glass to be measured, supports are distributed on the measurement surface of the measuring table at RPS points for point contact with the measured product and backstops are distributed to define the position of the measured shaped glass of the product on the measuring table. Precise localization of the measured product by means of backstops eliminates measurement errors.

In a preferred embodiment, the supports and the backstops are placed on magnetic clamps, which are distributed on the measurement surface of the measuring table in the direction of the x, y coordinates manually to a predetermined position of the measurement points. The positions are set by means of a laser beam perpendicular to the plane of the measurement surface of the measuring table, the heights of the supports being adjusted individually according to the shape of the measured shaped product to the coordinate value z of the respective measurement point. The magnetic clamps make it possible to ensure high flexibility of the device. An alternative to the manual placement of the magnetic clamps on the measurement surface of the measuring table is the mechanical placement by means of a distributor. In this embodiment, the magnetic clamps are distributed in the direction of the x, y coordinates by means of the distributor arranged above the measurement surface of the measuring table to the predetermined position of the measurement points. The heights of the supports are adjusted individually according to the shape of the measured product to the size of the z coordinate of the respective measurement point, either before placing the supports or after placing the supports in the respective x, y coordinates. If the measured product is automotive glass, the measurement points are determined by the glass manufacturer and are referred to as RPS points.

The advantage of the application of the mechanical distributor is quick and comfortable adjustment of the measuring table to a new product range.

In another alternative embodiment of the method, the supports and the backstops at the measurement points are fixedly mounted on a planar plate, the so-called pseudo-scale model which is placed on the measuring table on fixing mandrels defining its position.

The application of the pseudo-scale model is especially advantageous for determining geometric accuracy of the shape of automotive glass, since the pseudo-scale model ensures high accuracy in the placement of RPS points and backstops, whereby it is possible to perform external calibration measurements of the distribution of RPS points. In addition, it is possible to re-deploy the pseudo-scale model if the same range of products is produced after a certain time interval, because the pseudo-scale model can be stored and replaced as a whole.

For accurate measurement, the contactless measuring probes are formed by confocal probes, which emit rays of polychromatic white light towards the surface of the measured product and follow the ray reflected from the surface of the measured product and evaluate the wavelength of the received ray from which they determine the distance from the surface of the measured product. In all the above-mentioned embodiments of the method according to the present invention, the contactless measuring probes may be formed by ultrasound probes.

The ultrasound probes represent a cheaper alternative. However, they have worse measurement accuracy in the order of one tenth of a mm compared with confocal probes with accuracy in thousandths of mm. For fast operational measurements, integrated into production technology, transparent shaped flat products made of glass or plastics, the ultrasound probes can be used for setting production process parameters, etc. The principle of the device for performing the aforementioned method consists in that a measuring head fitted with a plurality of contactless measuring probes is arranged against the measurement surface of a measuring table, contactless measuring probes being arranged against the measurement surface of the measuring table, whereby the measuring head and the measuring table are arranged to allow relative movement during which the distance between the probes and the measurement surface of the measuring table remains constant. The contactless measuring probes are connected to a control unit, provided with the evaluation of measured z coordinate, which represents the distance of the contactless measuring probes from the upper surface of the measured shaped product, measured in respective x, y coordinates.

In a preferred embodiment, the measuring table is formed by a measuring conveyor with a movable measurement surface, on which the measured shaped products are placed, whereby the measuring head is stationary and is fixedly mounted on the frame of the measuring conveyor and extends across the entire width of the measuring conveyor, which may be part of the production line of the measured shaped products.

The contactless measuring probes are arranged in the measuring head in at least one row perpendicular to the direction of the relative movement of the measuring head and the measuring table.

It is advantageous for more shaped products if the contactless measuring probes are mounted in the measuring head displaceably in the direction towards and away from the measurement surface of the measuring table. By adjusting the measuring probes, their optimal distance from the measured product in the respective area can be achieved.

At the same time, the measuring head can be mounted displaceably in the measurement plane in a direction perpendicular to the direction of the relative movement of the measuring head and the measuring table, which is advantageous for measuring large products, for which a measuring head having dimensions smaller than those of the measured product can be used.

In another preferred embodiment, the measuring head can be provided with arms which are tilting at their ends in which measuring contactless measuring probes are mounted. This arrangement is intended for products which are very shaped at the edges.

The contactless measuring probes are formed by confocal probes or by ultrasound probes. In another preferred embodiment, the measuring table is rotatably mounted on a frame, its measurement surface being able to occupy a horizontal and measurement position.

To precisely define the position of the measured products on the measurement surface, the supports for point contact with the measured product and the backstops for defining the position of the measured product on the measurement surface of the measuring table are mounted on the measurement surface.

In one possible embodiment, the supports and the backstops are mounted on magnetic clamps which are displaceable with respect to the measurement surface and adjustable in a predetermined position on the measurement surface of the measuring table.

In another embodiment, the supports and the backstops are fixedly mounted at the measurement points on the pseudo-scale model plate. The pseudo-scale model can be fastened on the measurement surface of the measuring table by means of the fixing mandrels which define its position. The measured values of the distances are compared with the desired values at the respective points of the CAD model of the shaped glass very quickly, almost in online mode. Description of drawings

The method of contactless determination of the shape of shaped glass, in particular automotive glass, will be described with reference to several examples of embodiment of the invention, which are schematically represented in the enclosed drawings, wherein Fig. 1 shows a view of a basic embodiment of a device with a measuring table in a car position, Fig. 1a shows a view of a magnetic clamp with a support, Fig. 2 represents a view of another variant of the embodiment with a divided measuring head with tilting edge portions, Fig. 3 shows an embodiment of the device with a pseudo-scale model, Fig. 3a shows the mounting of the supports in the pseudo-scale model, Fig. 4 shows the device according to Fig. 1 with the measuring table in a horizontal position and Fig. 5 shows the device as part of the production line of the measured products.

Examples of embodiment

The method of contactless determination of geometric accuracy of the shape of a transparent shaped flat product made of glass or plastics will be explained with reference to a device for performing the method. The device will be described in exemplary embodiments which are given by way of example and the invention is not limited to these embodiments. Transparent shaped flat products made of glass or plastics are used in different fields, for example in architectural applications in building cladding, in solutions of the interior design of buildings, flats and in sanitary applications. The largest share of transparent shaped flat products made of glass or plastics is represented by automotive glass. This glass requires high dimensional and shape accuracy, allowing it to be installed in the relevant part of the car body with high precision.

A measuring table 3 is rotatably mounted on a frame 1 of the device. The measuring table 3 is in a known unillustrated manner coupled to a drive 2, which is also arranged on the frame 1. The drive 2 serves to tilt the measuring table 3 about the horizontal axis between its horizontal position and measurement position which during the measurement of the geometric accuracy of the shape of automotive glass corresponds to the position of the glass mounted on the car body - the so-called car position. In this measurement position (car position) the measuring table 3, or its measurement surface 31, usually has an almost vertical position. Parallel to the horizontal axis of rotation of the measuring table 3, linear guides 7 are arranged at its edges. On the linear guides 7 are mounted carriages 9 which are connected by a crossbar 8. In the crossbar 8 are formed a plurality of parallel holes in defined positions which accommodate contactless measuring probes H. The crossbar 8 constitutes together with the contactless measuring probes V\_ a measuring head 12. Ultrasound probes or confocal probes can be used as the contactless measuring probes H. Due to the dimensions of the contactless measuring probes LL_, especially confocal probes, the contactless measuring probes V\_ are arranged in several rows perpendicular to the direction of the movement of the measuring head 12, whereby the contactless measuring probes H in the individual rows are offset from one another. Both types of the contactless measuring probes LL_, i.e., both the ultrasound probes and the confocal probes, comprise an emitter of respective radiation and a sensor of respective radiation. The distance between the contactless probes H and the measurement surface 31 of the measuring table 3 is constant during their relative movement.

The shaped product 6 to be measured can be placed on the measuring table 3 in several ways.

In the embodiment of Fig. 1 , on the measurement surface 31 of the measuring table 3 are arranged magnetic clamps 15 on which either supports 4 or the backstops 5 are mounted. The supports 4 support the measured product from below and, when measuring automotive glass, they are placed at RPS points which are determined by the glass or car manufacturer as the points where the glass is to be supported during the measurement. The backstops 5 are arranged around the circumference of the glass. The locations for the backstops 5 are also predetermined by the manufacturer so that the position of the car glass 6 is unambiguous and precisely defined. The arrangement of the magnetic clamps 15 on the measurement surface 31 of the measuring table 3 is performed manually and automatically in the horizontal position of the measuring table 3. For manual distribution, the supports 4 and the backstops 5 are provided with aiming holes 41., 51 which enable to set them precisely to the predetermined position. The magnetic clamp 15 is shown together with the support 4 or the backstop 5 in Fig. 1a, the aiming hole 41, 51 being shown in a sectional view. On the measuring head 12 is mounted a transverse guide 17 on which a setting head L7L_ is mounted displaceably in a direction perpendicular to the linear guide 7. A laser emitter 16 is arranged in the setting head 171. The other transparent shaped flat products of glass or plastics are placed on the measurement surface 31 of the measuring table 3 in a similar manner.

Before placing the measured shaped product 6 on the measurement surface 31 of the measuring table 3 j the measuring head 12 starts to move forward without starting the contactless measuring probes H and the setting head L7L_ with the laser emitter 16 is moved to a position above the measurement surface 31 of the measuring table 3 in which the backstop 5 or the support 4 is to be arranged on the respective magnetic clamp 15. The magnetic clamp 15 on the measurement surface 31 is manually set to a position in which the beam of the laser emitter 16 passes through the aiming hole 51 of the respective stop 5 or the aiming hole 44 of the respective support 4. In this position, the magnetic clamp 15 is secured in a known manner and the measuring head 12 with the setting head L7L_ and the laser emitter 16 moves to the location of another backstop 5 or the supports 4 and their magnetic clamps 15 are manually set to a required position. After setting all the supports 4 and the backstops 5 and their magnetic clamps l^ the measuring head 12 moves to the initial position. The supports 4 are pre-set to the desired height. After the supports 4 and the backstops 5 have been set up, the product to be measured 6, for example automotive glass, is placed between the stops 5 on the supports 4.

For the automatic distribution of the magnetic clamps l^ the setting head 171 is provided with and coupled to a known drive (not shown) for setting its position in the y-axis on the measuring head 12, whereby the measuring head 12 serves to adjust the position of the setting head L7L_ in the x-axis. The measuring head 12 cooperates with the control unit of the device which stores information about the required positions of the magnetic clamps 15 for the backstops 5 or the supports 4, or this information is stored in another suitable means which is coupled to the control unit, or it may be stored in the measuring head 12. In addition, the setting head 171 is provided with means (not shown) for gripping the magnetic clamp 15 and releasing it at a designated location of the measurement surface 31 of the measuring table 3 and with a means for triggering its magnetic properties.

According to one of the variants of measurement, the measuring table 3 with the measuring head 12 subsequently turns by means of the drives 2 to a position, in which, in the case of the automotive glass measurement, the measured glass in the car position, the contactless measuring probes V\_ will be activated and the measuring head 12 is set in motion. Once the contactless measuring probes LL_ of the measuring head 12 get to the position against the measured glass, they start to obtain information about the distance z of the respective contactless measuring probes V\_ from the upper surface of the measured glass in the respective x and y coordinates. This information is either stored in the memory arranged in the measuring head 12, or in another suitable means which is connected to the measuring head 12, and subsequently it is compared with the information about the required shape of the respective type of the measured automotive glass. Other transparent shaped flat products 6 made of glass or plastics are measured in a similar manner.

The contactless measuring probes LL_ are connected|/coupled to the control unit which is provided with means for evaluating the distance z of the contactless measuring probes LL_ from the upper surface of the measured shaped product 6 in the respective coordinates (x, y), with operational memory and archive memory. The operational memory is used to store (temporarily) measured distances and, optionally, the calculated shape of the measured shaped product 6 and information about the correct shape of the product to be measured is stored in the archive memory. According to another of the possible measurement variants, the measuring table 3 remains in the horizontal position and the measuring head 12 with the contactless measuring probes LL_ moves above the measured product

6. In the exemplary embodiment of Fig. 2, which shows a specific illustration of the automotive glass, the product 6 to be measured is placed on the measurement surface 31 of the measuring table 3 as in the embodiment of Fig. 1. The manual setting of the magnetic clamps 15 by means of the setting head 171 and the laser emitter 16 is replaced by a mechanical distributor 13 which is displaceably mounted on an auxiliary crossbar m whose ends are displaceably mounted on an auxiliary linear guide 14 which is mounted in the vicinity of the edges of the measuring table 3 parallel with the linear guide 7. For the manual distribution of the magnetic clamps 15 with the supports 4 or with the backstops 5, the auxiliary linear guide 14 as well as the auxiliary crossbar m are provided with scales for setting the distributor 13 in the x, y coordinates. For the automatic distribution of the magnetic clamps l^ the distributor 13 is coupled to a well-known drive (not shown) for setting its position in the y axis and the auxiliary crossbar 141 is coupled to well-known drives (not shown) for setting the position of the auxiliary crossbar 141. or the position of the distributor 13 in the x axis. The two drives are coupled to the control device (not shown) in which information about the required positions of the clamps 15 for the backstops or the supports is stored. In both cases, the magnetic clamp 15 is inserted by the support 4 or by the backstop 5 into the gripping part of the distributor 13 by which it is moved to a predetermined position in which it is secured on the measurement surface 31 of the measuring table 3 and released from the distributor 13 into which the support 4 or the backstop 5 of other magnetic clamps 15 is/are inserted.

In the embodiment of Fig. 2, is shown an alternative embodiment of a measuring head 12 which is divided. The central part of the contactless measuring probes ϋ is mounted directly on the crossbar 8 in the same manner as in the embodiment of Fig. 1. The edge portions of the contactless measuring probes H are mounted on the tilting arms 10, which are rotatably mounted on the crossbar 8. Due to the fact that the measured products 6, in particular automotive glass, are in some cases markedly shaped, especially in the peripheral parts and also other measured products 6 may be shaped in a similar manner, the tilting arms 10 with the contactless measuring probes ϋ can be rotated to a position in which the axes of the contactless measuring probes H are as perpendicular as possible to the surface of the respective part of the measured shaped product 6, i.e., the axis of the contactless measuring probes 11 have the smallest possible deviation from the normal of the surface of the measured shaped product 6, which increases the accuracy of measurement of the shape of the peripheral parts of the measured shaped product 6,

In the embodiment of Fig. 3, on the measuring table 3 is placed a pseudo-scale model 18 formed by a plate on which supports 4 are placed at measurement points, for example, at RPS points in the case of measuring automotive glass 6, and backstops 5 around the circumference of automotive glass 6. The pseudo-scale model 18 is placed on the measuring table 3 by means of the fixing mandrels 19 which precisely define its position. For each type and dimensions of the measured automotive glass a special pseudo scale model 18 needs to be formed. In all the above-mentioned embodiments, the measured automotive glass 6 is placed with the same accuracy. Fig. 3a shows a detail of the fixed mounting of the support 4 in the plate of the pseudo scale model 18. The backstops 5 are arranged in the plate of the pseudo-scale model 18 in the same manner. Other transparent shaped flat products made of glass or plastics can be placed on the measurement surface 31 of the measuring table 3 also by means of the pseudo-scale model, which is important for products of large series of one specific embodiment. Flowever, in cases where there are more series of inspected products, because this solution allows transition from one measured shape to another without lengthy adjustment and, if necessary, allows a quick return to the originally measured shape.

In an unillustrated embodiment, the measuring head 12 with the contactless measuring probes V\_ is arranged on the arm of a robot, whereby the contactless measuring probes LL_ are in one plane which is parallel with the measurement surface of the measuring table 3. The robot is not mounted on the frame 1 of the device for contactless measurement but is provided with a device for maintaining a constant distance of the contactless measuring probes V\_ from the measurement surface 31 of the measuring table 3. The relative movement of the measuring head 12 and the measuring table 3 is in this embodiment caused by the movement of the measuring head 12, during which the contactless measuring probes H move in a plane which is parallel with the measurement surface 31 of the measuring table 3, whereby they perform a straight or curved path, either along a selected curve, or along general curve.

As to the movement of the measuring head 12 above the measured product 6, this movement can be replaced by the movement of the measuring table 3, whereby the measuring head 12 is stationary, or both the measuring table 3 and the measuring head 12 can move.

In case of lower requirements for the accuracy of the shape of the measured shaped product 6, the supports 4 can be omitted, the measured shaped product 6 is placed on the measurement surface 31 of the measuring table 3 between the backstops 5 and during rotation to the measurement position it is supported by the backstops 5 which approximately position each measured shaped product 6 without claims to accuracy.

In the embodiment according to Fig. 5, the measuring table 3 consists of a measuring conveyor 32 with a movable measurement surface 31, on which the shaped products 6 to be measured are placed during the measurement. The measuring head 12 is in this embodiment stationary and is fixedly mounted on the frame 320 of the measuring conveyor 32 and extends across the entire width of the measuring conveyor 32. In this embodiment, the measuring conveyor is part of the production line of the measured shaped products 6. The measured product 6 is conveyed by the unillustrated production line (not shown) to the input periphery 20 of the measuring device which terminates the production line upstream of the measuring conveyor 32 and from which the measured product 6 is transferred by means of a manipulator 21 onto the measurement surface 31 of the measuring conveyor 32 and set to the measurement position. The measurement surface 31 of the measuring conveyor 32 carries the measured product 6 under the measuring head 12. During the passage of the measured product 6 under the measuring head l^ geometric accuracy of the shape of the transparent shaped flat product is measured by using any of the above-described methods. The contactless measuring probes ϋ are connected/coupled to the control unit 23, which is provided with evaluating means 23 of the distance z of the contactless measuring probes H from the upper surface of the measured shaped product 6 in the respective x, y coordinates. At the end of the measuring conveyor 32, the product is gripped by the manipulator 21_ and transferred to the output periphery 22 of the measuring device which is connected to the measuring conveyor 32^ and further the product 6 continues to the parts of the production line further downstream. The above-mentioned described devices are used to carry out the method of measurement of geometric accuracy of the shape of transparent shaped flat products made of glass or plastics, especially automotive glass, whereby the method can also be performed in other devices which are not described. The transparent shaped flat product 6 to be measured is placed in a predetermined measurement position on the measurement surface 31 of the measuring table 3 against which is arranged the measuring head 12 fitted with a plurality of contactless measuring probes V\_ which are arranged against the measurement surface 31 and the measurement is started. The measuring head 12 and the measurement surface 31 of the measuring table move relative to each other during the measurement, whereby the measured product 6 passes under the measuring head 12, or between the measuring head 12 and the measurement surface 31 on which it is placed. During the relative movement of the measuring head 12 and the measurement surface 31^ the distance of the contactless measuring probes ϋ from the surface of the measured transparent shaped flat product is evaluated, whereupon these values are compared with the desired distance values in positions corresponding to the measurement positions, usually with the distance values at the corresponding points of the CAD model of the measured product 6.

Industrial applicability

The invention is intended especially for determining the shape of automotive glass but can also be used for determining geometric accuracy of the shape of other transparent shaped flat products made of glass or plastics, for example in architectural applications in building cladding, in solutions to the interior design of buildings, flats and in sanitary applications, the shapes of automotive lights and similar products. List of references

1 device frame

2 drive

3 measuring table

31 measurement surface

32 measuring conveyor

320 measuring conveyor frame

4 support

41 aiming hole of the support

5 backstop

51 aiming hole of the backstop

6 the measured product

7 linear guide

8 crossbar/crosspiece

9 carriage

10 tilting arm

11 contactless measuring probe

12 the measuring head

13 distributor

14 auxiliary linear guide

141 auxiliary crossbar

15 magnetic clamp

16 laser emitter

17 transverse guide of the adjusting head of the laser emitter 171 adjusting head of the laser emitter

18 pseudo-scale model

19 fixing mandrel of the pseudo-scale model

20 input peripheral devices of the measuring device

21 manipulator

22 output peripheral devices of the measuring device