Surface monitoring during heat treatment and press hardening

Abstract

The invention relates to an arrangement (1) for the heat treatment and press hardening of metal components (2), comprising: • a heat treatment device (3) for heat treatment of the components (2), • a pressing device (4) arranged downstream of the heat treatment device (3) for press hardening the components (2), • a monitoring device (5), which is arranged between the heat treatment device (3) and the pressing device (4) and which is designed to capture at least part of the surface (6) of the components (2), and to detect elevations (7) of the surface (6) of a size outside a tolerance, • and a separating device (8), which is arranged between the monitoring device (5) and the pressing device (4) and which is designed to separate, upstream of the pressing device (4), at least the components (2) in which an elevation (7) of the surface (6) of a size outside the tolerance has been detected by the monitoring device (5).

Description

[0001] Surface monitoring during heat treatment and press hardening

[0002] The invention relates to an arrangement and a method for heat treating and press hardening metallic components.

[0003] It is known to heat treat metal components and then form and harden them by pressing. For example, body components for motor vehicles are hardened in this way. However, press hardening can cause damage to the forming tool in the press if deposits form on the surface of the components during heat treatment. This can occur particularly with body components made of steel with an AlSi coating. The AlSi coating can, in particular, lead to residues on transport rollers used to transport the components through a continuous furnace. These residues, in turn, can be picked up by subsequent components and deposited on their surfaces. If a component with such deposits is placed in the press, this can damage the press.

[0004] There is therefore a need to create a heat treatment and press hardening process, particularly for body components made of steel with AlSi coating, that prevents damage to the forming tool in the press caused by deposits. However, such damage to the forming tool is independent of the component's intended purpose. Such damage to the forming tool can occur not only in steel components, but also in other metallic components. Furthermore, the cause of the deposits on the component surface is irrelevant to the damage. In addition to deposits of a coating material, the press can also be damaged by other undesirable protrusions on the component surface.

[0005] The object of the invention is therefore to provide an arrangement and a method for heat treating and press hardening metallic components, in which damage to a forming tool in a press due to undesirable elevations on the surface of the components is avoided.

[0006] These objects are achieved by the arrangement and method according to the independent claims. Further advantageous embodiments are specified in the dependent claims. The features presented in the claims and in the description can be combined with one another in any technologically expedient manner.

[0007] According to the invention, an arrangement for heat treating and press hardening metallic components is presented. The arrangement comprises:

[0008] ■ a heat treatment facility for heat treating the components,

[0009] ■ a pressing device downstream of the heat treatment device for press hardening the components,

[0010] ■ a monitoring device which is arranged between the heat treatment device and the pressing device and which is designed to at least partially detect a respective surface of the components and to detect elevations of the surface which are outside a tolerance range,

[0011] ■ a sorting device which is arranged between the monitoring device and the pressing device and which is designed to sort out at least the components in front of the pressing device in which a surface elevation of a size lying outside the tolerance has been detected by the monitoring device.

[0012] The arrangement allows components to be heat-treated and then press-hardened. The metallic components are preferably made of steel. Preferably, the components are components for a motor vehicle body. However, the intended use of the components is irrelevant to the functionality of the arrangement. It is also not necessary for the components to be made of steel. In general, the arrangement can be used for all components that can be heat-treated and then press-hardened.

[0013] The assembly allows multiple components to be heat-treated and press-hardened. The components can pass through the assembly individually, one after the other. Alternatively, the components can pass through the assembly in groups of adjacent components, with the individual groups passing through the assembly one after the other. The components are preferably identical to one another. The components are preferably heat-treated and press-hardened in the same way.

[0014] The arrangement allows the components to be heat-treated first. For this purpose, the arrangement comprises a heat-treatment device. The heat-treatment device is particularly designed to heat the components. Preferably, the heat-treatment device is designed to heat the components in some places to at least 700°C, in particular to at least 900°C. It is not necessary for the components to have their maximum temperature at an outlet of the heat-treatment device. The components can also be brought to a maximum temperature in the heat-treatment device and then cooled down again slightly before reaching the outlet of the heat-treatment device. At the outlet of the heat-treatment device, the components preferably have a temperature of at least 500°C, in particular of at least 700°C, for example of 930°C, at least in some places.

[0015] In the simplest case, the heat treatment facility can be formed by a single furnace. The precise design of the heat treatment facility is irrelevant to the functionality of the arrangement. It is sufficient that the heat treatment facility heat-treats the components in such a way that they can subsequently be press-hardened.

[0016] In particular, it is irrelevant whether the heat treatment facility consists of a single element or multiple elements. For example, the heat treatment facility can consist of a furnace and a tempering station downstream of the furnace. In the tempering station, the components can be heat-treated differently at different locations. For this purpose, the components can be heated and / or cooled differently at different locations. This locally different heat treatment can result in the components receiving different ductility during the subsequent press hardening.

[0017] The assembly allows the components to be press-hardened after heat treatment. For this purpose, the assembly includes a press device. The components can be formed and quenched using the press device. Quenching results in a structural transformation in the components. This hardens the components. The precise design of the press device is not important. The press device preferably includes a forming tool. One or more of the components can be inserted into the forming tool and press-hardened therein.

[0018] The arrangement preferably further comprises a transport device for transporting the components at least from the heat treatment device to the pressing device. The transport device can be formed, for example, by a roller conveyor with a plurality of rollers. The components can be transported on the rollers from the heat treatment device to the pressing device. The transport device can further be configured to transport the components through the heat treatment device. For this purpose, the roller conveyor can extend through the heat treatment device and from the heat treatment device to the pressing device. The rollers are preferably made of ceramic or steel. If the heat treatment device has one or more furnaces, the rollers in the region of the one furnace or the multiple furnaces are preferably made of ceramic, while the remaining rollers are preferably made of steel.The transport device can also be configured to insert the components into the pressing device. For this purpose, the transport device can have a transfer device for transferring the components from the roller conveyor to the pressing device. The transfer device can, for example, comprise a robot.

[0019] If a component with a sufficiently large surface elevation is inserted into the pressing device, this can damage the pressing device. This can be prevented with the described arrangement. For this purpose, the arrangement comprises a monitoring device arranged between the heat treatment device and the pressing device, which is configured to record a respective surface of the component and detect elevations of a size outside of a tolerance.

[0020] The monitoring system is designed to monitor the components during transport from the heat treatment facility to the pressing facility. This monitoring can also be referred to as inline monitoring.

[0021] The monitoring device is located upstream of the pressing device. The components pass through the monitoring device before reaching the pressing device. If a protrusion outside the tolerance range is detected on a component, this component can be rejected before reaching the pressing device. The pressing device, especially a forming tool of the pressing device, cannot then be damaged by this component.

[0022] Deposits of a coating material are particularly likely to be considered elevations. If the components are AlSi-coated steel components, for example, the AlSi can lead to residues on the rollers of the conveyor system, especially on the rollers of the conveyor system that are located in the area of ​​the heat treatment device. AlSi residues can occur in particular on rollers in a furnace. In general, residues on the rollers can be picked up by a subsequent component and lead to deposits on the surface of this component. However, the advantages described here can be achieved not only in the case of AlSi-coated steel components. In general, undesirable elevations on the surface of a component can lead to damage to the forming tool in the press. The cause of the undesirable elevation is irrelevant.The monitoring device can therefore generally detect undesirable elevations on the surface of a component.

[0023] In particular, the advantages described herein can be achieved with more than just coated components. Deposits of coating material can occur not only on components that are themselves coated. It is sufficient that the arrangement has previously been operated with a coated component. For example, if the arrangement is currently operated with uncoated components, coating material can be deposited on them that remained as residues on the rollers of the transport device from coated components previously treated with the arrangement. Furthermore, an undesirable elevation of a component surface can arise not only from the component picking up material that adhered to a roller. An undesirable elevation can arise for many different reasons.

[0024] Any change in the surface directed away from the component compared to a reference can be considered an elevation. The reference can be defined, in particular, based on the component itself, such that, for example, a discontinuity in the surface contour is identified as an elevation.

[0025] For the sake of linguistic simplicity, the raised surface is considered part of the component. If, for example, AlSi is deposited on the surface of a component, the deposited AlSi is considered part of that component. The surface of the component is formed in the area of ​​the deposited AlSi by the surface of the deposited AlSi. This definition applies regardless of whether the raised surface is formed by a foreign substance that is firmly attached to the component or by a foreign substance that is loosely attached to the component. For example, it is conceivable that a foreign body falls onto the top side of the component during heat treatment and remains there. The foreign body is then considered part of the component if the foreign body is moved with the component and could therefore enter the pressing device with the component. The surface of the component is formed in the area of ​​the foreign body by the surface of the foreign body.This definition makes sense because, on the one hand, it is irrelevant for potential damage to the pressing device whether the raised surface of the component is formed by a foreign body firmly attached to the component or by a foreign body loosely attached to the surface. This is all the more true because a foreign body that is initially only loosely attached to the surface of the component can bond with the component over the course of the process, particularly due to the prevailing temperatures. Due to the prevailing temperatures, chemical reactions can even occur, which would make it even more difficult to distinguish between the component and the foreign body. On the other hand, the nature of the raised surface is also irrelevant for determining the surface of the component.The monitoring device detects the surface of the component, regardless of whether the surface is formed by the component itself or additionally by the surface of a foreign body.

[0026] The monitoring device is designed to detect elevations on the surface of the component whose size lies outside a tolerance. The size of an elevation can be characterized by one or more parameters, in particular by a height and / or an extension in the component plane. The height indicates how far the elevation extends from the component surface. The height of the elevations is particularly preferably used as a measure of the size of the elevations. In general, it can be assumed that a high elevation can cause correspondingly great damage to the pressing device. The extension in the component plane can be defined by a maximum distance between two opposite edges of the elevation. Alternatively, the extension in the component plane can be defined by an x-value and a y-value relative to a fixed coordinate system.In each case, the tolerance is defined analogously to the size of the elevation.

[0027] Protrusions of a size outside the tolerance are so large that the corresponding components are rejected. Accordingly, the size at which this should be the case can be determined by selecting the tolerance. For example, the tolerance can be set in such a way that protrusions with a height of more than 0.5 mm are detected as protrusions of a size outside the tolerance. It is sufficient that the monitoring device can detect protrusions of a size outside the tolerance. In the simplest case, the tolerance corresponds to the measurement accuracy. Therefore, every measurable protrusion is regarded as a protrusion of a size outside the tolerance. In this case, the tolerance does not have to be stored in the monitoring device using one or more numerical values. Rather, the tolerance is inherent in the equipment used.

[0028] For example, the monitoring device can be capable of detecting protrusions that have a length of at least 2 mm, a width of at least 1 mm, and a height of at least 0.5 mm. The length is the extent of the protrusion in the component plane in the transport direction of the components, the width is the extent of the protrusion in the component plane perpendicular to the transport direction, and the height is the extent of the protrusion perpendicular to the component plane.

[0029] However, it is also possible for the monitoring device to continue to detect elevations of a size within the tolerance and then to identify elevations of a size outside the tolerance from the detected elevations, for example using a filter algorithm.

[0030] If one or more protrusions of a size outside the tolerance are detected on a component, the affected component can be rejected. For this purpose, the system comprises a rejection device, which is arranged between the monitoring device and the pressing device and is designed to reject at least those components upstream of the pressing device for which the monitoring device has detected a surface protrusion of a size outside the tolerance. The components rejected by the rejection device can be collected, for example, in a scrap container.

[0031] The rejection device is located upstream of the press. The components pass through the rejection device before reaching the pressing device. If a protrusion outside the tolerance range is detected on a component, this component can be rejected before reaching the press. This prevents the press from being damaged by this component.

[0032] The rejection device is used to reject at least those components upstream of the pressing device for which the monitoring device has detected a surface elevation of a size outside the tolerance. In addition, other components can also be rejected using the rejection device. The decision to reject a component can be made based on information obtained for other components using the monitoring device. For example, if several components are moved next to each other and simultaneously through the assembly, all of these components can be rejected together if a elevation of a size outside the tolerance is detected on at least one of these components. Pressing only the other components in the pressing device could lead to problems during pressing due to uneven pressure distribution. This could also complicate downstream logistics.In order to replace a single rejected component with a flawless one, such a flawless component would have to be available. However, this is generally not the case. Furthermore, the rejection facility may also reject components for reasons that are determined independently of surface defects.

[0033] The design of the sorting device is irrelevant. For example, the sorting device can be designed as the transfer device of the transport device. In this case, the transfer device can either insert the components into the pressing device or sort them out.

[0034] The rejection device can be used to prevent components with bumps so large that they could cause damage from entering the press device. In addition, the data acquired with the monitoring device can also be used to monitor the condition of the rollers in a transport system. Even smaller bumps can be recorded and processed for this purpose. If, for example, it is detected that bumps are becoming more and more frequent over time and / or are becoming larger, rollers can be examined and replaced if necessary before individual components have to be rejected. It can also be detected that bumps occur frequently at certain positions perpendicular to the transport direction of the components. This can indicate that the rollers have a particularly heavily contaminated track. This can then be specifically inspected.Furthermore, the data for individual components can be logged. Even if a component is not rejected because it does not exhibit any protrusions of a size outside the tolerance, this component may still have detected minor protrusions. This information can be assigned to the component and saved.

[0035] The monitoring device can at least partially detect the surface of the component. It is therefore sufficient to detect a section of the entire surface of the component. The component has a top side and a bottom side. In the definition of this term used herein, the surface is formed by the top side and the bottom side together.

[0036] It is sufficient for the monitoring device to be able to detect the component from one side. The monitoring device can therefore be configured to at least partially detect a respective underside of the components and / or at least partially detect a respective top side of the components. Preferably, the monitoring device is configured to completely detect a respective underside of the components and / or completely detect a respective top side of the components.

[0037] To detect the top surface, the monitoring device can have one or more sensors above the component transport level. The component can therefore be guided past the sensor(s) below this sensor(s). Raised top surfaces can occur, in particular, if a foreign body falls onto the component and remains there.

[0038] To detect the underside, the monitoring system can have one or more sensors below the component transport level. The component can therefore be moved past the sensor(s) above this sensor(s). Bumps on the underside can occur, in particular, when coating material from a previously treated component is deposited on the component via the rollers of the transport system. Detection of the underside is particularly important in many applications.

[0039] To detect both the top side and the bottom side, the monitoring device can have one or more sensors above the transport plane for the components and one or more sensors below the transport plane for the components. This combination is particularly preferred because it enables comprehensive monitoring of the components. For damage to the forming tool of the pressing device, it is generally irrelevant whether the elevation was on the bottom side or on the top side. Since the deposition of coating material on the bottom side of the component is of particular importance in many applications, a preferred embodiment of the arrangement provides for the monitoring device to be designed to detect a respective bottom side of the components.

[0040] In a further preferred embodiment, the arrangement further comprises a transport device with a plurality of rollers for transporting the components at least from the heat treatment device to the pressing device, wherein the monitoring device is arranged below the rollers and is designed to detect the respective underside of the components through a gap between two of the rollers of the transport device.

[0041] The particularly preferred detection of the underside of the components is generally difficult because the transport device is usually located underneath the components. In the present embodiment, this problem is solved in that the respective surface of the components is detected through a gap between two of the rollers of the transport device. Admittedly, the entire underside is never visible to the monitoring device through this gap. However, this is irrelevant because the underside can be continuously detected while the component moves past the gap. The preferred embodiment described below is an example of this.

[0042] In a further preferred embodiment of the arrangement, the monitoring device is configured to record, for each of the components, a plurality of height profiles of the surface of the corresponding component formed transversely to a transport direction of the components and to detect, on the height profiles for the corresponding component, the elevations of the surface of a size lying outside the tolerance.

[0043] Each of the height profiles indicates the contour of one of the components at a specific position in the transport direction of the components, with the contour running perpendicular to the transport direction of the components. For each of the components, a plurality of such height profiles is recorded, with each of the height profiles being recorded at a different position on the component in the transport direction of the components. In the simplest case, this is possible because the monitoring device always records the height profiles at the same position while the components are moved past the monitoring device in the transport direction. The spatial distance between the height profiles is then determined by the frequency at which the height profiles are recorded. The height profiles are preferably recorded at a frequency in the range of 0.1 to 10 kHz, in particular 0.5 to 3 kHz.For example, at a transport speed of 1.5 m / s and a frequency of 1 kHz, 666 height profiles are recorded per meter of the component's extension in the transport direction. This results in a height profile spacing of 1.5 mm. Accordingly, in the example, elevations of 1.5 mm in length can be detected. The length indicates the extension of the elevations in the transport direction of the components.

[0044] The surface of the component can be composed of the individual height profiles, whereby the gaps between the individual height profiles can be closed by interpolation. In this way, a three-dimensional data model of the component's surface can be generated from the height profiles. However, for the arrangement to function, it is not necessary that this option actually be used. In particular, it is not necessary that a three-dimensional data model of the component's surface be displayed to a user. It is sufficient that the acquired data be evaluated as described herein.

[0045] A height profile is a two-dimensional data set that contains a height value for a multitude of spatial coordinates. The spatial coordinate indicates the position perpendicular to the transport direction of the component. The height value can be specified as an absolute value or as a difference from a reference value. The reference value can be set such that a smooth surface constantly has a height value of zero.

[0046] The elevations are detected relative to the remaining surface of the component. This has the significant advantage that it is sufficient to capture the component from one side. This applies even though the component generally moves slightly up and down in the vertical direction, for example, while being moved by rollers of a conveyor system. If the height of the elevations were specified by an absolute height relative to the monitoring device, the up and down movement of the components could lead to significant miscalculations. These errors are avoided in the present embodiment by capturing the elevations along the individual height profiles.

[0047] The elevations are recorded individually on the elevation profiles. For this purpose, the elevation profiles can be individually subjected to a corresponding algorithm. The algorithm can, for example, detect whether and, if so, where a elevation profile has a value that deviates from a zero line by more than a limit value defined by the tolerance. Such an evaluation of a two-dimensional data set is easily possible.

[0048] In a further preferred embodiment of the arrangement, the monitoring device is designed to detect the respective surface of the components according to the light section principle.

[0049] The principle of light sectioning is well known. A light beam is directed onto the surface to be measured in such a way that a line of light is created on the surface. This is possible, for example, with a line laser. A camera captures the line of light on the surface. The camera signal can then be used to specify the contour of the surface in three-dimensional coordinates. The principle of light sectioning can be implemented, in particular, using laser triangulation sensors.

[0050] In a further preferred embodiment of the arrangement, the monitoring device comprises a plurality of sensors which are arranged next to one another transversely to a transport direction of the components.

[0051] In the present embodiment, the components can be covered over a particularly large width. For this purpose, several sensors are arranged next to one another. It is sufficient for each of the sensors to cover part of the width to be monitored. This reduces the demands on the sensors. Each of the sensors preferably monitors one lane. Adjacent lanes preferably overlap, so that seamless monitoring is possible. The data recorded with the individual sensors can then be combined. In particular, a plurality of height profiles can be created for each of the components from the data recorded with the individual sensors. Depending on the size of the components, a height profile of a component can comprise data from one, several, or all of the sensors. The sensors are preferably laser triangulation sensors.

[0052] In a further preferred embodiment of the arrangement, the heat treatment device comprises a continuous furnace and / or a chamber furnace.

[0053] Deposits of coating material can occur, particularly in a continuous furnace. In a chamber furnace, residues of coating material can occur at contact points. Furthermore, a chamber furnace can also have rollers for transporting components into and out of the chamber furnace. The advantages described here can therefore be achieved with both a continuous furnace and a chamber furnace. Since it is irrelevant whether the heat treatment facility is formed by a single element or multiple elements, a combination of a continuous furnace and a chamber furnace is also possible.

[0054] As a further aspect of the invention, a method for heat-treating and press-hardening metallic components is presented. The method comprises the following steps for each of the components: a) heat-treating the component, b) checking whether a surface of the component has a protrusion of a size outside a tolerance after step a), wherein the method further comprises one of the following steps for each of the components: d) rejecting the component, c2) press-hardening the component, wherein at least those components are rejected according to step d) for which a protrusion of a size outside the tolerance was detected in step b).

[0055] The advantages and features of the arrangement are applicable and transferable to the method, and vice versa. The arrangement is preferably configured for operation according to the method. For this purpose, the arrangement preferably has a correspondingly configured control device. The method is preferably carried out using the arrangement.

[0056] Step a) is preferably carried out using a heat treatment device. This is preferably designed as described above. Step b) is preferably carried out using a monitoring device. This is preferably designed as described above. Step c1) is preferably carried out using a sorting device. This is preferably designed as described above. Step c2) is preferably carried out using a pressing device. This is preferably designed as described above. In step d), at least those components are sorted out for which a projection of a size lying outside the tolerance was detected in step b). In addition, components can also be sorted out for other reasons.

[0057] In a preferred embodiment of the method, the components pass through steps a) to c) in groups at the same time, wherein in step d) all components of a group are rejected if, for at least one of the components of this group, a surface elevation of a size outside the tolerance has been detected in step b).

[0058] The present embodiment is an example in which in step d) not only the components are separated out for which a protrusion of an out-of-tolerance size was detected in step b).

[0059] In this embodiment, several components are moved through the assembly next to one another and thus simultaneously. The adjacent components are referred to as a group. In this embodiment, all components in a group are rejected together if a protrusion of an out-of-tolerance size is detected on at least one of the components in this group. This generally means that perfect components are also rejected. However, pressing only the perfect components in a group in the pressing device could lead to problems due to uneven pressure distribution. Replacing a single rejected component with a subsequent component could disrupt the cycle.

[0060] In a further preferred embodiment of the method, the components are coated.

[0061] The components are preferably coated with AlSi. The components are preferably already coated before step a).

[0062] Particularly with coated components, deposits can occur as raised surfaces, as described above. While the coating of one component usually only leads to raised surfaces on a subsequent component, several identical components are usually treated one after the other using this arrangement.

[0063] The invention is explained in more detail below with reference to the figures. The figures show a particularly preferred embodiment, to which the invention is not limited, however. The figures and the proportions depicted therein are merely schematic. They show:

[0064] Fig. 1 a: a side view of an arrangement according to the invention for heat treating and press hardening metallic components,

[0065] Fig. 1 b: a plan view of the arrangement of Fig. 1 a,

[0066] Fig. 1c: a cross-sectional view of the arrangement of Fig. 1a and 1b,

[0067] Fig. 2: a height profile recorded with the arrangement from Fig. 1a to 1c.

[0068] Fig. 1a to 1c show an arrangement 1 for heat treating and press hardening metallic components 2. The arrangement 1 is described using a coordinate system which is formed by a first direction x, a second direction y and a third direction z.

[0069] The components 2 can in particular be steel plates coated with AlSi.

[0070] The assembly 1 comprises a heat treatment device 3 for heat-treating the components 2. The heat treatment device 3 is only partially shown. The heat treatment device 3 comprises a continuous furnace 17, which is also only partially shown in Figs. 1a to 1c.

[0071] Furthermore, the arrangement 1 comprises a pressing device 4 downstream of the heat treatment device 3 for press hardening the components 2. The pressing device 4 is also only partially shown in Figs. 1a to 1c.

[0072] Furthermore, the arrangement 1 comprises a transport device 12 with a plurality of rollers 13 for transporting the components 2 through the heat treatment device 3 and from the heat treatment device 3 to the pressing device 4. The transport device 12 can transport the components 2 in a transport direction r. In the illustrated embodiment, the transport direction r corresponds to the first direction x.

[0073] Furthermore, the arrangement 1 comprises a monitoring device 5, which is arranged between the heat treatment device 3 and the pressing device 4 and which is designed to detect a respective surface 6 of the components 2 and to detect elevations 7 of the surface 6 of a size lying outside a tolerance.

[0074] Furthermore, the arrangement 1 comprises a sorting device 8, which is arranged between the monitoring device 5 and the pressing device 4 and which is designed to sort out at least those components 2 in front of the pressing device 4 in which an elevation 7 of the surface 6 of a size lying outside the tolerance has been detected by the monitoring device 5.

[0075] The monitoring device 5 is configured to detect a respective underside 9 of the components. For this purpose, the monitoring device 5 is arranged below the rollers 13 and configured to detect the respective surface 6 of the components 2 through a gap 14 between two of the rollers 13 of the transport device 12. As an alternative to the exemplary embodiment in Figs. 1a to 1c, the monitoring device 5 could also be arranged above the components 2 and configured to detect a respective upper side 10 of the components 2. As a further alternative to the exemplary embodiment in Figs. 1a to 1c, such a monitoring device 5 arranged above the components 2 could be provided below the components 2 in addition to the monitoring device 5 shown in Figs. 1a to 1c.

[0076] The monitoring device 5 is designed to record, for each of the components 2, a plurality of height profiles 15 of the surface 6 of the corresponding component 2 formed transversely to the transport direction r of the components 2 (shown in Fig. 2), and to detect, for the corresponding component 2, on the height profiles 15, the elevations 7 of the surface 6 of a size lying outside the tolerance.

[0077] The monitoring device 5 is configured to detect the respective surface 6 of the components 2 according to the principle of light sectioning. For this purpose, the monitoring device 5 comprises several laser triangulation sensors as sensors 16, which are arranged next to one another transversely to the transport direction r of the components 2. This can be seen in Fig. 1b and particularly clearly in Fig. 1c. The six sensors 16 together form the monitoring device 5.

[0078] Each of the sensors 16 comprises a laser 20, which, as shown in Fig. 1a, emits a line of light onto the surface 6 of the components 2. Each of the sensors 16 also comprises a camera 21, which in particular captures the line of light on the surface 6 of the components 2. The sensors 16 record a plurality of height profiles 15 for each of the components 2, one of which is shown as an example in Fig. 2. Each of the height profiles 15 indicates the position of the surface 6 of the component 2 in the z-direction relative to a reference position selected as the zero point. The height profile 15 extends in the y-direction across the entire width of the component 2. The height profile 15 is therefore a plot of the deviation Az in the z-direction against the y-position. The height profiles 15 are all recorded at the same x-position. This x-position is shown in Fig. 1 a insofar as the light emitted by the laser 20 strikes the underside 9 of the component 2 at this x-position.Because the components 2 move in the transport direction r, i.e. in the x-direction, the components 2 can be recorded by periodically recording height profiles 15 over their entire extension in the x-direction.

[0079] The arrangement 1 further comprises a control device 11. In particular, by means of this control device, the arrangement 1 shown in Fig. 1a to 1c is set up to carry out a method for heat treatment and press hardening of the metallic components 2, which method comprises the following steps for each of the components 2: a) heat treatment of the component 2 with the heat treatment device 3, b) checking with the monitoring device 5 whether the surface 6 of the component 2 has an elevation 7 of a size outside the tolerance after step a).

[0080] The method further comprises one of the following steps for each of the components 2: c1) separating the component 2 with the separating device 8, c2) press hardening the component 2 with the pressing device 4.

[0081] At least the components 2 are separated according to step c 1 ) with the separation device 8 for which a protrusion 7 of a size outside the tolerance was detected in step b).

[0082] The components 2 pass through steps a) to c) simultaneously in groups 18, 19. In the exemplary embodiment in Fig. 1a to 1c, a first group 18 and a second group 19 are shown as examples. Each of the groups 18, 19 is formed by six of the components 2, which are transported through the arrangement lying next to one another in the y-direction. The two groups 18, 19 pass through the arrangement 1 at a distance from one another. This distance is not shown to scale in the figures. The aim is merely to demonstrate the principle that several components 2 are transported in groups 18, 19 and the groups 18, 19 are transported one after the other through the arrangement 1.

[0083] In step d), all components 2 of a group 18, 19 are rejected if, for at least one of the components 2 of this group 18, 19, an elevation 7 of the surface 6 of a size outside the tolerance has been detected in step b).

[0084] Fig. 2 shows one of the height profiles 15 of one of the components 2 recorded with the arrangement 1 from Fig. 1a to 1c. It can be seen that the height profile 15 extends in the y-direction across the width of the component 2. Plotted against the y-position is a difference Az between a measured value for the z-position of the surface 6 of the component 2 and a reference value. The reference value is selected such that the deviation Az is consistently zero for a flat surface 6. In the example shown, however, a downward deflection can be seen. This is recorded as an elevation 7 on the surface 6. Depending on the size of the deflection, the associated elevation 7 can be identified as being outside the tolerance.

[0085] List of reference symbols

[0086] 1 arrangement

[0087] 2 component

[0088] 3 Heat treatment facility

[0089] 4 Pressing device

[0090] 5 Monitoring device

[0091] 6 Surface

[0092] 7 Survey of size outside of tolerance

[0093] 8 Separation facility

[0094] 9 Bottom

[0095] 10 Top

[0096] 11 Control device

[0097] 12 Transport device

[0098] 13 roll

[0099] 14 gap

[0100] 15 Elevation profile

[0101] 16 Sensor

[0102] 17 Continuous furnace

[0103] 18 first group

[0104] 19 second group

[0105] 20 lasers

[0106] 21 Camera r Transport direction x first direction y second direction z third direction

[0107] Az deviation

Claims

Claims 1. Arrangement (1) for heat treating and press hardening metallic components (2), comprising: ■ a heat treatment device (3) for heat treating the components (2), ■ a pressing device (4) downstream of the heat treatment device (3) for press hardening the components (2), ■ a monitoring device (5) which is arranged between the heat treatment device (3) and the pressing device (4) and which is designed to at least partially detect a respective surface (6) of the components (2) and to detect elevations (7) of the surface (6) of a size lying outside a tolerance, ■ a sorting device (8) which is arranged between the monitoring device (5) and the pressing device (4) and which is designed to sort out at least the components (2) in front of the pressing device (4) in which an elevation (7) of the surface (6) of a size lying outside the tolerance has been detected by the monitoring device (5).

2. Arrangement (1) according to claim 1, wherein the monitoring device (5) is designed to detect a respective underside (9) of the components (2).

3. Arrangement (1) according to claim 2, further comprising a transport device (12) with a plurality of rollers (13) for transporting the components (2) at least from the heat treatment device (3) to the pressing device (4), wherein the monitoring device (5) is arranged below the rollers (13) and is designed to detect the respective underside (6) of the components (2) through a gap (14) between two of the rollers (13) of the transport device (12).

4. Arrangement (1) according to one of the preceding claims, wherein the monitoring device (5) is designed to detect, for each of the components (2), a plurality of height profiles (15) of the surface (6) of the corresponding component (2) formed transversely to a transport direction (r) of the components (2) and to determine on the height profiles (15) for the corresponding component (2) the To detect elevations (7) of the surface (6) of a size outside the tolerance.

5. Arrangement (1) according to one of the preceding claims, wherein the monitoring device (5) is designed to detect the respective surface (6) of the components (2) according to the principle of light section.

6. Arrangement (1) according to one of the preceding claims, wherein the monitoring device (5) comprises a plurality of sensors (16) which are arranged next to one another transversely to a transport direction (r) of the components (2).

7. Arrangement (1) according to one of the preceding claims, wherein the heat treatment device (3) comprises a continuous furnace (17) and / or a chamber furnace.

8. A method for heat treating and press hardening metallic components (2), wherein the method comprises the following steps for each of the components (2): a) heat treating the component (2), b) checking whether a surface (6) of the component (2) after step a) has a protrusion (7) of a size lying outside a tolerance, wherein the method further comprises one of the following steps for each of the components (2): d) rejecting the component (2), c2) press hardening the component (2), wherein at least those components (2) are rejected according to step d) for which a protrusion (7) of a size lying outside the tolerance was detected in step b).

9. Method according to claim 8, wherein the components (2) in groups (18, 19) each undergo steps a) to c) simultaneously, and wherein in step c 1 ) all components (2) of a group (18, 19) are rejected if, for at least one of the components (2) of this group (18, 19), an elevation (7) of the surface (6) of a size outside the tolerance has been detected in step b).

10. Method according to claim 8 or 9, wherein the components (2) are coated.

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