Apparatus for analyzing the surface of stones and system for producing stones

Abstract

The present invention discloses an apparatus (1) for analyzing the surface of at least one stone (S), the apparatus (1) having a transport support (10) for supporting at least one stone (S) and for transporting the same in a transport direction (T), at least one 3D surface scanner (20) which is configured to determine a topography of at least one surface (SO) of the stone (S), at least one white-light line illumination device (31, 32) for emitting linear white light towards the transport support (10), an RGB camera (50) for detecting light which has been emitted by the white-light line illumination device (31, 32) and has been reflected by the at least one surface (SO) of the at least one stone (S), and a control device (60) which is data-coupled to the at least one 3D surface scanner (20) and to the RGB camera (50), wherein the control device (60) is designed to receive topography data representing the topography of the at least one surface (SO) of the at least one stone (S) from the 3D surface scanner (20) and to receive reflection data representing the reflective capability of the at least one surface (SO) of the stone (S) from the RGB camera (50) and to determine a height difference of the topography of the at least one surface (SO) of the at least one stone (S) on the basis of the topography data and to output an error signal if the height difference is greater than a maximum height difference, and to determine a reflectivity of the at least one surface (SO) of the stone (S) on the basis of the reflection data and to output an error signal if the reflectivity is outside a predefined reflectivity range.Fig. 1

Description

Full specificationApparatus for analyzing the surface of stones and system for producing stones BACKGROUND[1] The present invention relates to an apparatus for analyzing the surface of stones. The present invention further relates to a system for producing stones. [2] During the production of stones, in particular the production of concrete blocks, such as paving stones, hollow blocks, curbstones, edging stones and the like, the stones may have defects. These defects can include cracks, segregation, edge fractures, or color defects on the surface of the stone. [3] Quality assurance of concrete blocks produced using a stone-making machine, for example, has up to now been carried out predominantly by people who assess purely subjectively whether the produced stones meet the quality requirements. If a defective stone is identified, it is manually removed from a conveyor belt. SUMMARY[4] The present invention is based on the object of providing an apparatus for analyzing the surface of at least one concrete block, which allows for objective, fast and more accurate quality assurance of produced stones, in particular concrete blocks. [5] This object underlying the present invention is achieved by an apparatus for analyzing the surface of at least one stone having the features of claim 1. Advantageous embodiments of the apparatus are described in the claims dependent on claim 1. [6] More precisely, the object underlying the present invention is achieved by an apparatus for analyzing the surface of at least one stone, wherein the apparatus has a transport support for supporting and transporting at least one stone in a transport direction, wherein the transport support extends in the transport direction and in a transverse direction. The apparatus further has at least one 3D surface scanner which is configured to determine a topography of at least one surface of the stone, wherein the 3D surface scanner is spaced from the transport support in a vertical direction perpendicular to the transport direction and perpendicular to the transverse direction. Furthermore, the apparatus has at least one white-light line illumination device for emitting linear white light towards the transport support, wherein a longitudinal extent of the linear white light is oriented substantially parallel to the transverse direction of the transport support, and wherein the white-light line illumination device is spaced in the vertical direction from the transport support. Furthermore, the apparatus includes an RGB camera for detecting light emitted by the white-light line illumination device and reflected by the at least one surface of the at least one stone, wherein the RGB camera is spaced in the vertical direction from the transport support and is arranged so as to be spaced in the transport direction from the 3D surface scanner. The apparatus has a control device that is data-coupled to the at least one 3D surface scanner and to the RGB camera, wherein the control device is designed to receive topography data representing the topography of the at least one surface of the at least one stone from the 3D surface scanner and reflection data representing the reflective capability of the at least one surface of the stone from the RGB camera, and to determine a height difference of the topography of the at least one surface of the at least one stone based on the topography data and to output an error signal if the height difference is greater than a maximum height difference, and to determine a reflectivity of the at least one surface of the stone based on the reflection data and to output an error signal if the reflectivity is outside a predetermined reflectivity range. [7] The apparatus according to the invention allows for objective, fast and more accurate quality assurance of manufactured stones, in particular concrete blocks. The apparatus according to the invention allows for the determination of a topography of the surface of the at least one stone and also the determination of a color or color gradient of the surface of the at least one stone. This allows structural defects and color defects in the stone surface to be reliably identified. [8] The surface of the at least one stone includes, for example, a top surface and / or one or more side surfaces and / or edges of the at least one stone. [9] The transport support can be designed as a conveyor belt or transport belt. The transport support is driven by a drive device. The transport direction and the transverse direction preferably span a plane that is horizontally aligned in the installed position of the apparatus. The transport support can be part of a stone machine. Preferably, the transport support is designed to accommodate a plurality of stones, which can further preferably be positioned in a plurality of ordered rows on the transport support. 

[10] The 3D surface scanner can be designed to emit a structured light pattern towards the transport support. Based on the light pattern detected by the 3D surface scanner on the surface of the at least one stone, its topography can be determined, since the emitted light pattern is known. 

[11] The topography of a stone's surface is to be understood as its surface structure. The apparatus is preferably designed in such a way that it can determine the surface structure of a stone with an accuracy of up to 0.1 mm. 

[12] The at least one white-light line illumination device is preferably designed as an LED white-light line illumination device having a plurality of white-light-emitting LEDs arranged along a longitudinal extent of the white-light line illumination device. 

[13] The RGB camera has a CCD sensor. The CCD sensor is further preferably designed as a CCD line sensor. 

[14] The control device is designed as an electronic control device. The control device is designed to receive data from the 3D surface scanner and / or the RGB camera and / or to transmit data, in particular control signals, to them. Furthermore, the control device is preferably data-coupled to the at least one white-light line illumination device for transmitting control signals. 

[15] The reflectivity or reflective capability of the at least one surface is calculated based on the known color and emission characteristics of the at least one white-light line illumination device and the reflection data received by the RGB camera. 

[16] Preferably, the apparatus is designed such that it has a first white-light line illumination device and a second white-light line illumination device, each of which is signal-coupled to the control device, wherein the first white-light line illumination device and the second white-light line illumination device have a first horizontal distance to each other in the transport direction. In this case, a first emission direction of the first white-light line illumination device forms a first angle with the vertical direction, and a second emission direction of the second white-light line illumination device forms a second angle with the vertical direction. The first horizontal distance, the first angle, and the second angle are set such that the first linear white light emitted by the first white-light line illumination device and the second linear white light emitted by the second white-light line illumination device coincide on a surface of the stone. 

[17] The correspondingly designed apparatus allows for an even more precise determination of the reflective capability of the at least one surface of the stone. Since of the linear white light shining onto the surface of the stone at the first angle and at the second angle, shadows caused by the topography of the stone surface can be calculated out. This avoids false error signals. 

[18] Preferably, the first angle and the second angle have the same magnitude. For example, the first angle is 35° and the second angle is -35°. 

[19] Preferably, the magnitude of the first angle and the second angle lies between 20° and 60°, more preferably between 25° and 50°, and even more preferably between 30° and 40°. 

[20] Preferably, the first white-light line illumination device and the second white-light line illumination device have the same vertical distance to the transport support. Further preferably, the first white-light line illumination device and the second white-light line illumination device are arranged symmetrically to each other with respect to a plane of symmetry spanned by the vertical and transverse directions. 

[21] Preferably, the distance of the RGB camera to the transport support, running parallel to the vertical direction, is greater than the distance of the first white-light line illumination device and / or the second white-light line illumination device to the transport support, running parallel to the vertical direction. 

[22] Further preferably, the distance of the RGB camera to the transport support, running parallel to the vertical direction, is between 500 mm and 1500 mm, more preferably between 700 mm and 1200 mm, and even more preferably between 800 mm and 1000 mm. 

[23] Further preferably, the distance parallel to the vertical direction between the first white-light line illumination device and / or the second white-light line illumination device and the transport support is between 150 mm and 500 mm, more preferably between 150 mm and 400 mm, and even more preferably between 150 mm and 300 mm. 

[24] Preferably, the distance between the first white-light line illumination device and the second white-light line illumination device, running parallel to the direction of transport, is between 100 mm and 500 mm, more preferably between 150 mm and 400 mm, and even more preferably between 200 mm and 300 mm. 

[25] Further preferably, the apparatus is designed such that the RGB camera is arranged in the transport direction between the first white-light line illumination device and the second white-light line illumination device. 

[26] A suitably designed apparatus has the advantage of having compact dimensions. This is because the space between the first white-light line illumination device and the second white-light line illumination device is used by the RGB camera. Furthermore, by correspondingly arranging the RGB camera in relation to the first and second white-light line illumination devices, a more precise determination of the reflective capability of the at least one surface of the stone is made possible, as incorrect determinations of the reflective capability due to misinterpretation of topography-caused shadows are reduced. This avoids false error signals. 

[27] Furthermore, preferably the RGB camera has the same distance to the first white-light line illumination device and to the second white-light line illumination device in the direction of transport. 

[28] Preferably, in the apparatus, the RGB camera is designed as an RGB line sensor, wherein a longitudinal extent of the RGB line sensor runs parallel to the first linear white light and to the second linear white light, and wherein the RGB line sensor is arranged and aligned between the first white-light line illumination device and the second white-light line illumination device in such a way that the surface of the stone, which is illuminated by the first linear white light and / or by the second linear white light, can be optically detected by the RGB line sensor. 

[29] The correspondingly designed apparatus allows for the determination of the reflective capability of the at least one surface of the at least one stone when there is an increased transport speed of the stone due to the transport support. Since of the reduced number of pixels to be read from the RGB line sensor, the corresponding data can be processed electronically more quickly. 

[30] Further preferably, the apparatus is designed such that the first white-light line illumination device and / or the second white-light line illumination device are mounted at a variable distance from the transport support. 

[31] The correspondingly designed apparatus has the advantage that stones with different height extents can be analyzed. Since of the variable spacing of the first white-light line illumination device and / or the second white-light line illumination device, these can always be positioned with respect to the transport support in such a way that a line focus of the first white-light line illumination device and / or of the second white-light line illumination device is always on at least one surface of the at least one stone. 

[32] Further preferably, in the apparatus the control device is designed to activate the first white-light line illumination device and the second white-light line illumination device at different times by transmitting control signals. 

[33] The correspondingly designed apparatus allows for an even more precise determination of the reflective capability of the at least one surface of the stone. Since of the linear white light shining onto the surface of the stone at the first angle and at the second angle, shadows caused by the topography of the stone surface can be calculated out. This avoids false error signals. 

[34] Preferably, the control device of the apparatus is configured to receive the first reflection data representing the reflective capability of the at least one surface of the stone from the RGB camera for light in a red wavelength range, and to determine a first reflectivity of the at least one surface of the stone in the red wavelength range based on the first reflection data and to output an error signal if the first reflectivity is outside a predetermined first reflectivity range. Alternatively or in addition, the control device is configured to receive the second reflection data representing the reflective capability of the at least one surface of the stone from the RGB camera for light in a green wavelength range, and to determine a second reflectivity of the at least one surface of the stone in the green wavelength range based on the second reflection data and to output an error signal if the second reflectivity is outside a predetermined second reflectivity range. Alternatively or in addition, the control device is configured to receive the third reflection data representing the reflective capability of the at least one surface of the stone from the RGB camera for light in a blue wavelength range, and to determine a third reflectivity of the at least one surface of the stone in the blue wavelength range based on the third reflection data and to output an error signal if the third reflectivity is outside a predetermined third reflectivity range. 

[35] The correspondingly designed apparatus allows for a more accurate determination of the color or color gradient of the surface of the at least one stone. This allows for a more reliable detection of color defects in the stone surface. 

[36] Preferably, the 3D surface scanner in the apparatus is configured to emit a structured light pattern towards the transport support, to detect the at least one surface of the at least one stone illuminated by the structured light pattern, and to calculate the topographic data of the at least one surface of the at least one stone based on the detected image data. 

[37] The correspondingly designed apparatus allows for a fast and highly precise determination of the topography of the surface of the at least one stone. Thus, the correspondingly designed apparatus allows for a reliable determination of the topography of the stone surface even at high transport speeds of the transport support and therefore of the at least one stone or the plurality of stones. 

[38] The apparatus is preferably designed in such a way that it can determine the surface structure of a stone with an accuracy of up to 0.1 mm. 

[39] Preferably, the apparatus has at least two 3D surface scanners, each of which optically detects a surface region of the transport support, wherein the surface regions are adjacent to each other and / or partially overlapping. 

[40] Using the correspondingly designed apparatus, larger surface regions of the transport support can be optically detected. Thus, the correspondingly designed apparatus allows for an increased throughput of stones to be analyzed. 

[41] Preferably, the apparatus is designed such that it has a light absorption device which is arranged in the transport direction between the at least one 3D surface scanner and the RGB camera and extends in the vertical direction, preferably up to the transport support. 

[42] The correspondingly designed apparatus exhibits improved accuracy in determining the topography of the surface of the at least one stone and in determining a color or color gradient of the surface of the at least one stone, since the light emitted by the at least one white-light line illumination device is not detected by the 3D surface scanner, and since the light emitted by the 3D surface scanner is not detected by the RGB camera. This allows structural defects and color defects in the stone surface to be identified even more reliably. 

[43] The light absorption device is preferably designed as a light-tight curtain. 

[44] Preferably, the control device of the apparatus is designed to correct the reflectivity of the at least one surface of the at least one stone, taking into account the topography data. 

[45] The correspondingly designed apparatus allows for a more accurate determination of the color or color gradient of the surface of the at least one stone. This allows for a more reliable detection of color defects in the stone surface. This is because by taking into account the determined topography of the surface of the at least one stone, it is possible to identify or anticipate the resulting shadows caused by irradiation of the surface by the at least one white-light line illumination device. 

[46] Preferably, the transport support of the apparatus is designed so that a plurality of stones can be placed on it and transported in the transport direction, wherein the control device is designed to identify, when at least one error signal is output, the at least one stone for which the error signal was output. 

[47] The correspondingly designed apparatus allows for even faster quality assurance of produced stones, in particular concrete blocks. Furthermore, sorting work, which may be carried out by an operator of the apparatus, is considerably facilitated. 

[48] The apparatus preferably further has a display device for indicating the at least one identified defective stone. 

[49] The correspondingly designed apparatus allows for even faster quality assurance of produced stones, in particular concrete blocks. Furthermore, sorting work, which may be carried out by an operator of the apparatus, is considerably facilitated. 

[50] The display device is preferably designed as a monitor. Furthermore, it is possible for the display device to project an optical signal (illumination) onto the defective stone, thus simplifying the sorting process even further. 

[51] The apparatus preferably further has a removal apparatus for removing the at least one identified defective stone. 

[52] The correspondingly designed apparatus has an increased degree of automation, so that the apparatus has an increased throughput of stones to be analyzed. 

[53] The removal apparatus is preferably designed as a robot that uses a gripper arm to remove the stones identified as defective from the transport support. 

[54] The underlying object on which the present invention is based is also achieved by a system for producing stones, in particular concrete blocks, having the features of claim 15. 

[55] In more detail, the object underlying the present invention is achieved by a system for producing stones, in particular concrete blocks, which has a stone machine for producing stones and a first apparatus for surface analysis as described above, wherein the first apparatus is arranged on a wet side of the system. The system further has a second surface analysis apparatus as described above, wherein the second apparatus is arranged on a dry side of the system. 

[56] The wet side of the system is preferably located directly downstream of the stone machine, so that the still wet or moist stones can be analyzed using the first surface analysis apparatus. The dry side of the system is a region of the system where the stones are in dried form. For example, the damp stones are fed into a storage and / or drying device. Then the dry side of the system is located downstream of the storage and / or drying device in the direction of transport of the stones. Thus, the dry stones can be analyzed using the second surface analysis apparatus. 

[57] The correspondingly designed system has a yet further improved reliability in surface analysis, as the surfaces of the stones can change again during the drying process.BRIEF DESCRIPTION OF THE DRAWINGS

[58] Further advantages, details, and features of the invention can be found below in the described exemplary embodiments. In detail in the drawings:Fig. 1: is a schematic cross-sectional view of an apparatus according to the invention for analyzing the surface of at least one stone;Fig. 2: is a schematic plan view of the apparatus shown in Fig. 1 for analyzing the surface of at least one stone; andFig. 3: is a schematic and highly simplified representation of a system according to the invention for the production of stones. DETAILED DESCRIPTION

[59] In the following description, the same reference signs denote the same components or features; in the interest of avoiding repetition, a description of a component made with reference to one drawing also applies to the other drawings. Furthermore, individual features that have been described in connection with one embodiment can also be used separately in other embodiments. Furthermore, the methods in accordance with the first to seventh embodiments can also be combined with one another. 

[60] Fig. 1 shows an apparatus 1 for analyzing the surface of at least one stone S in a cross-sectional representation. Fig. 2 shows the apparatus 1 depicted in Fig. 1 in a plan view of a transport support 10 of the apparatus 1. The transport support 10 is designed for supporting and transporting a plurality of stones S in a transport direction T. As can be seen from Fig. 1 and 2, the transport support 10 extends in the transport direction T and in a transverse direction Q. 

[61] The apparatus 1 further has at least one 3D surface scanner 20. For the sake of clarity, only a single 3D surface scanner 20 is shown in Fig. 1, whereas in Figure three 3D surface scanners 20 of the apparatus 1 are shown. The 3D surface scanners 20 are configured to determine a topography of the surfaces SO of the stones S. As can be seen in particular from Fig. 1, the 3D surface scanners 20 are spaced apart from the transport support 10 in a vertical direction V, which is oriented perpendicular to the transport direction T and to the transverse direction Q. 

[62] As can be seen in particular from Fig. 2, the 3D surface scanners 20 are designed to optically detect each region 11, 12, 13 of the transport support 10. In the illustrated embodiment, a first surface region 11 is adjacent to a second surface region 12, wherein the first surface region 11 and the second surface region 12 partially overlap. A third region 13 is arranged adjacent to the second region 12 and also partially overlaps with the second region 12. 

[63] Furthermore, the apparatus 1 has at least one white-light line illumination device 31, 32 for emitting linear white light towards the transport support 10. In the illustrated embodiment, the apparatus 1 has a first white-light line illumination device 31 and a second white-light line illumination device 32, which are shown only in Fig. 1, but not in Fig. 2. It is evident that the first white-light line illumination device 31 and the second white-light line illumination device 32 have a first horizontal distance D to each other in the transport direction T. 

[64] The white-light line illumination devices 31, 32 are arranged and aligned such that a first emission direction 41 of the first white-light line illumination device 31 encloses a first angle α1 with the vertical direction V, and that a second emission direction 42 of the second white-light line illumination device 32 encloses a second angle α2 with the vertical direction V. The first horizontal distance D, the first angle α1 and the second angle α2 are set such that the first linear white light emitted by the first white-light line illumination device 31 and the second linear white light emitted by the second white-light line illumination device 32 coincide on a surface SO of a stone S. The longitudinal extent L of the linear white light runs substantially parallel to the transverse direction Q of the transport support 10. 

[65] The white-light line illumination devices 31, 32 are spaced in the vertical direction V from the transport support 10. 

[66] In order to allow the apparatus 1 to be used for stones S with different height extents, the first white-light line illumination device 31 and the second white-light line illumination device 32 are mounted at variable distances to the transport support 10. 

[67] The apparatus 1 further includes an RGB camera 50 for detecting light emitted by the white-light line illumination devices 31, 32 and reflected from the surface SO of a stone S. The RGB camera 50, which in the illustrated embodiment is designed as an RGB line sensor 50, is spaced in the vertical direction V from the transport support 10. Furthermore, the RGB camera 50 is spaced in the transport direction T from the 3D surface scanner. 

[68] Fig. 1 shows that the apparatus 1 further has a control device 60, which is not shown in Fig. 2. The control device 60 is data-coupled to the 3D surface scanners 20 and to the RGB camera 50. Furthermore, the control device is signal-coupled to the first white-light line illumination device 31 and to the second white-light line illumination device 32. The control device 60 can be designed to activate the first white-light line illumination device 31 and the second white-light line illumination device 32 at different times by transmitting control signals. 

[69] As described above, in the illustrated embodiment the RGB camera 50 is designed as an RGB line sensor 50. In this case, a longitudinal extent of the RGB line sensor 50 runs parallel to the first linear white light emitted by the first white-light line illumination device 31 and to the second linear white light emitted by the second white-light line illumination device 32. The RGB line sensor 50 is arranged and aligned between the first white-light line illumination device 31 and the second white-light line illumination device 32 in such a way that the surface SO of the stone S which is illuminated by the first linear white light and / or by the second linear white light can be optically detected by means of the RGB line sensor 50. 

[70] The control device 60 is designed to receive topography data representing the topography of the surfaces SO of the stones S from the 3D surface scanner 20. Furthermore, the control device 60 is designed to receive reflection data representing the reflectivity SO of the surfaces of the stones S from the RGB camera 50. Based on the topography data, a height difference of the topography of the surfaces SO is determined for each stone S and an error signal is output if the height difference is greater than a maximum height difference. Furthermore, based on the reflection data, a reflectivity of each of the surfaces SO of the stones S is determined and an error signal is output if the reflectivity is outside a predetermined reflectivity range. 

[71] In the embodiment of the apparatus 1 shown in Fig. 1, it has a display device 80. The control device 60 is designed to identify, when an error signal is output, at least one stone S for which the error signal was generated and / or output. The stone S identified as faulty is displayed on or by means of the display device 80. 

[72] As can be seen from Fig. 1, the apparatus 1 also has a light absorption device 70, which can be designed for example as an opaque plate or curtain. The light absorption device 70 is arranged in the transport direction T between the 3D surface scanner 20 and the RGB camera 50 and extends in the vertical direction V. The light absorption device 70 absorbs light generated by the first and second white-light line illumination devices 31, 32 and reflected from the surfaces SO of the stones S towards the 3D surface scanner 20. Furthermore, the light absorption device 70 absorbs light generated by the 3D surface scanners 20 and reflected from the surfaces SO of the stones S towards the RGB camera. 

[73] Fig. 3 shows a system 100 for producing stones S. The system S includes a stone machine 110 for producing stones S. Furthermore, the system has a first apparatus 1 shown in Fig. 1 and 2 and a second apparatus 1 shown in Fig. 1 and 2. The first apparatus 1 is arranged on a wet side 120 of the system 100. In the illustrated embodiment, the wet side 120 is arranged in the transport direction T of the transport support 10 between the stone machine 110 and a storage system 140. The storage system 140 can, for example, be designed as a storage rack system with multiple storage racks 140. The storage racks 140 can be designed to be movable and can preferably be supplied to a drying apparatus, for example an oven for drying the stones S. The second apparatus 1 is arranged on a dry side 130 of the system 100. The dry side 130 of the system 100 is a region of the system 100 in which the stones S are in dried form.List of reference signs 1 Apparatus for surface analysis10 Transport support11 First surface region (of the transport support)12 Second surface region (of the transport support)13 Third surface region (of the transport support)20 3D surface scanner31 First white-light line illumination device32 Second direction of emission (of the second white-light line illumination device)41 First direction of emission (of the first white-light line illumination device)42 Second white-light line illumination device50 RGB camera / RGB line sensor60 Control device70 Light absorption device80 Display device / Monitor100 System for producing stones110 Stone machine120 Wet side (of the stone machine)130 Dry side (of the stone machine)140 Storage of the system for producing stonesD Horizontal distance (between first and second white-light line illumination device)L Longitudinal extent of the linear white lightQ Transverse directionS StoneSO Surface of the stoneT Transport directionV Vertical directionZL Line sensor longitudinal extentα1 First angleα2 second angle

Claims

1. An apparatus (1) for analyzing the surface of at least one stone (S), wherein the apparatus (1) has the following features:- a transport support (10) for supporting and transporting at least one stone (S) in a transport direction (T), wherein the transport support (10) extends in the transport direction (T) and in a transverse direction (Q);- at least one 3D surface scanner (20) which is configured to determine a topography of at least one surface (SO) of the stone (S), wherein the 3D surface scanner (20) is spaced from the transport support (10) in a vertical direction (V) perpendicular to the transport direction (T) and to the transverse direction (Q);- at least one white-light line illumination device (31, 32) for emitting linear white light towards the transport support (10), wherein a longitudinal extent (L) of the linear white light is oriented substantially parallel to the transverse direction (Q) of the transport support (10), and wherein the white-light line illumination device (31, 32) is spaced in the vertical direction (V) from the transport support (10);- an RGB camera (50) for detecting light which has been emitted by the white-light line illumination device (31, 32) and has been reflected by the at least one surface (SO) of the at least one stone (S), wherein the RGB camera (50) is spaced in the vertical direction (V) from the transport support (10) and spaced in the transport direction (T) from the 3D surface scanner (20); and- a control device (60) which is data-coupled to the at least one 3D surface scanner (20) and to the RGB camera (50), wherein- the control device (60) is designed to- receive topography data representing the topography of the at least one surface (SO) of the at least one stone (S) from the 3D surface scanner (20) and- to receive reflection data representing the reflective capability of the at least one surface (SO) of the stone (S) from the RGB camera (50), and- to determine a height difference of the topography of the at least one surface (SO) of the at least one stone (S) on the basis of the topography data and to output an error signal if the height difference is greater than a maximum height difference, and- to determine a reflectivity of the at least one surface (SO) of the stone (S) on the basis of the reflection data and to output an error signal if the reflectivity is outside a predefined reflectivity range. 2. The apparatus (1) according to claim 1, characterized by the following features:- the apparatus (1) has a first white-light line illumination device (31) and a second white-light line illumination device (32), each of which is signal-coupled to the control device (60);- the first white-light line illumination device (31) and the second white-light line illumination device (32) have a first horizontal distance (D) to each other in the transport direction (T);- a first emission direction (41) of the first white-light line illumination device (31) forms a first angle (α1) with the vertical direction (V), and a second emission direction (42) of the second white-light line illumination device (32) forms a second angle (α2) with the vertical direction (V); and- the first horizontal distance (D), the first angle (α1) and the second angle (α2) are set such that the first linear white light emitted by the first white-light line illumination device (31) and the second linear white light emitted by the second white-light line illumination device (32) coincide on a surface (SO) of the stone (S). 3. The apparatus (1) according to claim 2, characterized in that the RGB camera (50) is arranged in the transport direction (T) between the first white-light line illumination device (31) and the second white-light line illumination device (32). 4. The apparatus (1) according to claim 2, characterized by the following features:- the RGB camera (50) is designed as an RGB line sensor (50);- a line sensor longitudinal extent of the RGB line sensor (50) runs parallel to the first linear white light and to the second linear white light;- the RGB line sensor (50) is arranged and aligned between the first white-light line illumination device (31) and the second white-light line illumination device (32) in such a way that the surface (SO) of the stone (S) which is illuminated by the first linear white light and / or by the second linear white light can be optically detected by means of the RGB line sensor (50). 5. The apparatus according to claim 2, characterized in that the first white-light line illumination device (31) and / or the second white-light line illumination device (32) are mounted at a variable distance from the transport support (10). 6. The apparatus according to claim 2, characterized in that the control device (60) is designed to activate the first white-light line illumination device (31) and the second white-light line illumination device (32) at different times by transmitting control signals. 7. The apparatus according to claim 1, characterized in that the control device (60) is designed- to receive first reflection data representing the reflective capability of the at least one surface (SO) of the stone (S) from the RGB camera (50) for light in a red wavelength range, and- to determine a first reflectivity of the at least one surface (SO) of the stone (S) in the red wavelength range on the basis of the first reflection data and to output an error signal if the first reflectivity is outside a predefined first reflectivity range; and / or- to receive second reflection data representing the reflective capability of the at least one surface (SO) of the stone (S) from the RGB camera (50) for light in a green wavelength range, and- to determine a second reflectivity of the at least one surface (SO) of the stone (S) in the green wavelength range on the basis of the second reflection data and to output an error signal if the second reflectivity is outside a predefined second reflectivity range; and / or- to receive third reflection data representing the reflective capability of the at least one surface (SO) of the stone (S) from the RGB camera (50) for light in a blue wavelength range, and- to determine a third reflectivity of the at least one surface (SO) of the stone (S) in the blue wavelength range on the basis of the third reflection data and to output an error signal if the third reflectivity is outside a predefined third reflectivity range. 8. The apparatus according to claim 1, characterized in that the 3D surface scanner (20) is designed- to emit a structured light pattern towards the transport support (10),- to detect the at least one surface (SO) of the at least one stone (S) illuminated with the structured light pattern, and- to calculate the topographic data of the at least one surface (SO) of the at least one stone (S) based on the detected image data. 9. The apparatus according to claim 1, characterized by the following features:- the apparatus has at least two 3D surface scanners (20) that each optically detect a region (11, 12, 13) of the transport support (10); and- the regions (11, 12, 13) are adjacent to each other and / or partially overlapping. 10. The apparatus (1) according to claim 1, characterized in that the apparatus (1) has a light absorption device (70) which is arranged in the transport direction (T) between the at least one 3D surface scanner (20) and the RGB camera (50) and extends in the vertical direction (V), preferably up to the transport support (10). 11. The apparatus (1) according to claim 1, characterized in that the control device (60) is designed to correct the reflectivity of the at least one surface (SO) of the at least one stone (S) taking into account the topographic data. 12. The apparatus (1) according to claim 1, characterized by the following features:- the transport support (10) is designed so that a plurality of stones (S) can be supported on it and transported in the transport direction (T);- the control device (60) is designed to identify, when at least one fault signal is output, the at least one stone (S) for which the fault signal was output. 13. The apparatus (1) according to claim 12, characterized in that the apparatus (1) has a display device (80) for displaying the at least one identified defective stone (S). 14. The apparatus (1) according to claim 12, characterized in that the apparatus (1) has a removal apparatus for removing the at least one identified defective stone (S). 15. A system (100) for producing stones (S), having- a stone machine (110) for producing stones (S);- a first apparatus (1) for surface analysis according to claim 1, wherein the first apparatus (1) is arranged on a wet side (120) of the system (100); and- a second apparatus (1) for surface analysis according to claim 1, wherein the second apparatus (1) is arranged on a dry side (130) of the system (100).

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