Object manipulator for x-ray inspection apparatus

Abstract

The invention relates to an object manipulator 1 for an X-ray inspection device, comprising: a stage 6 on which an inspection object 22 can be fixed; a first linear guide (4) along which the stage (6) is movable in a first direction; a second linear guide 5 along which the stage 6 can be moved in a second direction, the second direction having a component perpendicular to the first direction, in particular perpendicular to the first direction, a stage interface 10 being formed on the first linear guide 4, the stage 6 having an interface region 8, the objective table 6 is detachably connected to the objective table interface 10 at an interface region via a connecting device, the objective table 6 has a contact region 9 on which the objective table 6 is arranged in the contact region 9 so as to be positionally changeable from the first linear guide 4, and the objective table is configured separately from the interface region 8. In particular at the end thereof facing away from the interface region 8.

Description

Technical Field

[0001] The invention relates to an object manipulator for an X-ray inspection device, the object manipulator having an object carrier on which an inspection object can be fixed. Background Art

[0002] When non-destructive testing of a test object is performed by means of X-rays, an X-ray device is used, which uses an X-ray tube and an X-ray detector as an imaging system. The test object to be tested must be placed in the optical path and can be moved in the optical path. In order to be able to move the test object, the test object is fixed on an object manipulator, which can make the test object move linearly along different moving axes and rotate around different rotation axes, wherein the corresponding required direction and rotation axis depend on the method to be performed (for example, in rotational tomography). In the object manipulator used so far, the stage on which the test object can be fixed is placed on a thin stage support. Such a thin stage support cannot be manufactured with high precision. In addition, under high loads, the stage support bends. Both of these lead to the stage being unable to be stably placed or not being well oriented relative to the moving axis, rotation axis and center line of the X-ray source. The stage is usually positioned in the hole of the stage support by two pins. Depending on the tolerances of the pins or the holes that receive the pins, the stage can move when the axes are moved on the stage support. When replacing or exchanging the stage, the position of the stage can change. This affects the repeatability of the position and complicates the calibration of the stage with respect to the movement axes, the rotation axes and the center beam of the X-ray inspection system. This also applies due to the different degrees of deflection of the stage support in the case of test objects of different weights. Summary of the invention

[0003] The object of the present invention is to provide an object manipulator in which the repeatability is improved after a replacement of the object stage.

[0004] Accordingly, the object is achieved by an object manipulator having a carrier having a first linear guide and a second linear guide, along which the carrier is movable in two directions, which are regularly selected perpendicular to one another and are referred to as X and Z directions, wherein a carrier interface is constructed on the first linear guide and the carrier has an interface area, at which the carrier is detachably connected to the carrier interface via a connecting device, wherein the carrier further has a rest area, in which the carrier is arranged on the first linear guide in a positionally variable manner relative to the first linear guide and the carrier is constructed to be positionally separated from the interface area, the carrier preferably being constructed at its end facing away from the interface area. Since the thin stage supports used to date tend to bend easily and thus cannot achieve good reproducibility on test objects of different weights, which are distributed on different stages, a stage with significantly higher dimensional stability compared to the stage support has now been replaced, which is supported on the first linear guide without the intermediate stage support, thus optimizing the repeat positioning accuracy when replacing or exchanging the stage. In addition, the stage can be manufactured with high precision, which is different from the production of the stage supports used to date.

[0005] An advantageous development of the invention provides that the first linear guide has two parallel guide rails and / or the second linear guide has two parallel guide rails, wherein the guide rails are in particular round or rectangular linear axes. This eliminates the need for the linear guides known from the prior art, which must be manufactured cost-intensively as machined parts, and instead allows for a more cost-effective solution in the form of a purchased part.

[0006] Another advantageous development of the invention provides that the connecting device has two screws, in particular clamping screws, which cooperate with the carrier interface and the interface region. This allows extremely reliable and precise positioning of the replaced carrier at the location of the previous carrier. The repeat positioning accuracy is thus extremely high and undesired changes in the relative position of the carrier with respect to the first linear guide are avoided.

[0007] Another advantageous improvement of the invention provides that the connection device has a first stop mechanism and a third stop mechanism at the stage interface, and that the connection device has a second stop mechanism and a fourth stop mechanism at the interface region, wherein the second stop mechanism is pressed against the first stop mechanism by means of a pressing device, and the fourth stop mechanism is pressed against the third stop mechanism. Since the stop mechanism cannot move on the plane spanned by the first and second directions of the two linear guides (which is usually referred to as the XZ plane of the object manipulator) due to the pressing device, extremely reliable and precise positioning of the replaced stage at the position of the previous stage is achieved, which is the same as described by means of the design solution explained in the previous paragraph. Therefore, in the design solution described in this paragraph, the repeat positioning accuracy is also extremely high.

[0008] Another advantageous development of the invention provides that the first stop means and the third stop means are respectively a linear shaft or a cylindrical pin, which extend substantially perpendicularly to the first direction and the second direction, and wherein the second stop means is a straight stop edge extending in the first direction, and wherein the fourth stop means is a body having a first stop face and a second stop face, the respective orientations of which have directional components which are not parallel to the stop edges, and wherein one directional component has a positive angle with respect to the second direction and the other directional component has a negative angle with respect to the second direction, wherein the angle between the two orientations is in particular 90°. As a result, an exact and reproducible fixing of the exchangeable carrier is ensured by very simple means, and the system is not overdetermined, so that the system rests on the specified abutment surface in a defined manner. In this case, the force of the pressing device presses the carrier with its abutment edge and the two stop faces against the linear shaft or the cylindrical pin, wherein a movement of the carrier in the direction of the plane spanned by the two linear guides (as mentioned above, this is the XZ plane of the object manipulator) is no longer possible.

[0009] Another advantageous development of the invention provides that at least one of the linear axes or cylindrical pins can be moved relative to the carrier interface in a direction having a component in the second direction and / or the straight stop edge can be moved in a direction having a component in the second direction. For example, if the linear axis or the cylindrical pin cooperating with the device edge is moved, the carrier is rotated about the other linear axis or the other cylindrical pin; the same applies to the corresponding movement of the stop edge. If regular designations of the directions are used (see above), this corresponds to a rotation about the Y direction, i.e. perpendicularly to the plane spanned by the carrier. By means of this rotation, an orientation of the contact edge and the horizontal axis of rotation about a first direction (usually the X direction) and a second direction (usually the Z direction) can be achieved.

[0010] Another advantageous development of the invention provides that the pressing device has a spring having a force component along the second direction, and the pressing device is in particular a lateral pressure piece. This implementation is particularly simple and is possible with means already available on the market.

[0011] Another advantageous development of the invention provides that the actuator has both two screw-shaped connection devices and a connection device with first to fourth stop means. The respective advantages of the above-mentioned embodiments are thus combined with one another.

[0012] Another advantageous development of the invention provides that two supports, in particular rotating running wheels, are arranged on the platform interface, which supports the movement of the platform interface together with the platform in a first direction, wherein at least one of these supports, preferably both supports, can be moved in a third direction, which has both a component perpendicular to the first direction and a component perpendicular to the second direction, wherein the third direction is preferably perpendicular to the first direction and the second direction. If the two supports are adjusted identically, a rotation about the first direction (usually the X direction) is achieved. If only one of the supports or both supports are adjusted differently, a rotation about the second direction (usually the Z axis) is performed inversely. This involves an only very small height change, which has a very small overall effect, wherein the second rotation is then not exactly about this second direction, but due to the twisting of the platform, a rotation parallel to the Z axis is the result. In addition to the rotating running wheels mentioned above as possible supports, all other known supports for rolling bearings can also be used; likewise, instead of rolling bearings, sliding bearings can also be used, wherein known sliding bodies can then be used as supports.

[0013] Another advantageous development of the invention provides that at least one of the two support bodies can be moved by an eccentric device. This design can be adjusted very finely using commercially available tools. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Now, further details and advantages of the present invention will be described in detail based on the embodiments shown in the drawings. It is shown that:

[0015] Figure 1 A schematic diagram of a known X-ray inspection device with drawn axes and movement directions of a manipulator is shown,

[0016] Figure 2 A first embodiment of a manipulator according to the invention is shown in a perspective view,

[0017] Figure 3 Show Figure 2 A schematic cross-sectional view of the manipulator in FIG.

[0018] Figure 4 A part of a second embodiment of a manipulator according to the invention is shown in a top view,

[0019] Figure 5 Shows Figure 4 Some of the improvements in

[0020] Figure 6 Show according to Figure 5 A side view of a modification of the embodiment of the invention viewed in the Z direction, with details regarding the rotation about a line parallel to the X axis,

[0021] Figure 7 Show Figure 5 and 6 A schematic cross-sectional view perpendicular to the X-axis of an improved scheme, and

[0022] Figure 8 is with Figure 6 A similar side view showing details of the rotation about a line parallel to the Z axis. DETAILED DESCRIPTION

[0023] Figure 1 The structure of an X-ray inspection device is schematically shown in an exemplary manner. The X-ray inspection device has an X-ray tube 2 that emits X-rays (not shown), and opposite to the X-ray tube 2, the X-ray inspection device also has an X-ray detector 3 that detects X-rays from the X-ray source 2. An object manipulator 1 is arranged between the X-ray tube and the X-ray detector, and an inspection object 22 (see Figure 3 ), the inspection object is irradiated with X-rays. The movement of the X-ray tube 2 and the X-ray detector 3 may not be important for the present invention, so they are not shown.

[0024] A Cartesian coordinate system is shown, the orientation of which corresponds to the usual practice, but another orientation is also possible. The Y axis extends vertically in the direction of the X-rays emitted by the X-ray tube 2. The Y direction and the Z direction extend parallel to the plane spanned by the surface of the object manipulator 1. In terms of the invention, possible linear and rotational movements of the stage 6 are given (see Figures 5 to 8 ). This involves linear movements parallel to the X-axis (referred to as XO), the Y-axis (referred to as YO) and the Z-axis (referred to as ZO) as well as rotational movements about axes parallel to the X-axis (referred to as XOR), the Y-axis (referred to as YOR) and the Z-axis (referred to as ZOR).

[0025] Figure 2 The structure of an object manipulator 1 according to the invention is shown in a perspective view. The object manipulator extends substantially (except for its height extension in the Y direction) in a plane parallel to the XZ plane. Figure 2 The mode of operation of the components shown and their interaction have not yet been fully discussed within the scope of the explanation of the figures; this will be discussed in more detail below within the scope of the explanation of the other figures.

[0026] The lowermost layer of the manipulator 1 forms a second linear guide 5, which has two parallel guide rails (third guide rail 5a and fourth guide rail 5b). The first linear guide 4 is arranged on the second linear guide 5, which has two parallel guide rails (first guide rail 4a (in the form of profile rail 4a) and second guide rail 4b (in the form of circular linear shaft 4b)). The guide rails 4a, 4b of the first linear guide 4 are oriented perpendicularly to the guide rails 5a, 5b of the second linear guide 5.

[0027] A loading platform 6 is arranged on the first linear guide 4 and can be moved relative to the first linear guide along the first guide rail 4a and the second guide rail 4b. The loading platform 6 is supported on the second guide rail 4b with one end thereof (hereinafter referred to as the supporting area 9) by a supporting body not shown in detail and not illustrated. The end of the loading platform facing away from the supporting area 9 (hereinafter referred to as the interface area 8) is detachably connected to the object interface 10. This connection is achieved by two clamping screws 14, 15 and by four stop mechanisms 12, 13, 16, 17 and a pressing device 23 (the detailed embodiment of this and the cooperation of these components are described below). Figure 4 and Figure 5 ) system. A circular receiving recess 7 is formed in the sample carrier 6, in which a test object 22 can be fixed on the sample carrier 6 (see Figure 3 ).

[0028] The stage interface 10 is connected via Figure 6 and Figure 8 The support bodies 20, 21 shown in FIG. 1 are movably connected to the second guide rail 4b. The stage interface 10 is provided in its region ( Figure 2 The right side of the middle part has a step 11, on which the interface area 8 of the loading platform 6 rests. The first stop mechanism 12 and the third stop mechanism 13 are arranged on the loading platform interface 10, while the second stop mechanism 16 and the fourth stop mechanism 17 are arranged on the loading platform 6.

[0029] Figure 3A highly schematic section of an object manipulator 1 parallel to the YZ plane is shown. The object carrier 6 lies on two guide rails 4a, 4b extending perpendicularly to the plane of the paper. In the support area 9, the object carrier lies directly on the guide rails and in the interface area 8 is supported by the object carrier interface 10. In order to ensure that the object carrier 6 is fixed in position relative to the object carrier interface 10, the two components are connected by means of two clamping screws 14, 15. This excludes relative movements between the object carrier 6 and the object carrier interface 10 and thus relative movements of the first linear guide 4 and the second linear guide 5 of the object manipulator 1. Regardless of which object carrier is installed in the manipulator after replacing the object carrier 6, its position and thus the position of the test object 22 fixed in its receiving recess 7 are accurately determined, so that when the test object 22 is subjected to an X-ray inspection, no inaccuracies / errors will occur when reconstructing the test object 22 from the data obtained during the X-ray inspection due to positioning inaccuracies. This makes it possible to easily replace the object stage without having to elaborately adjust the object manipulator 1 again after the replacement has taken place. Below the object stage 6 an X-ray tube 2 is shown which can be moved relative to the object stage 6 .

[0030] Unlike the prior art, when a circumferential stage support in contact with the two guide rails 4a, 4b is used, into which the stage 6 is inserted, the above advantages are achieved according to the invention by only using a stage interface 10 that cooperates on one side with the first guide rail 4a of the first linear guide 4, together with a part of the stage 6 (its contact area 9) that cooperates directly with the second guide rail 4b of the first linear guide 4. In contrast to the stage supports made of sheet metal used to date, the solid stage 6 can be manufactured with high precision. Due to its solid design, in contrast to the stage supports used previously, no bending in the Y direction occurs when test objects 22 of different weights are loaded.

[0031] Figure 4 A section of the worktable 6 in its interface region 8 is shown in a top view (opposite to the Y direction) in conjunction with the worktable interface 10. In addition to the two clamping screws 14, 15 already described in detail above, by which relative movements between the worktable 6 and the worktable interface 10 are prevented after the worktable 6 has been precisely oriented on the worktable interface 10, a precise orientation can also be achieved with the aid of additional structures.

[0032] This structure acts by means of the four stop means 12, 13, 16, 17 together with a pressing device 23, the action of which is indicated by the force arrow denoted by F. The pressing device 23 presses the carrier 6 to the left against the fixed carrier interface 10 (e.g. by means of a spring force) so that the second stop means 16 is pressed against the first stop means 12 and the third stop means 17 is pressed against the second stop means 13. For example, a lateral pressure piece can be used as the pressing device 23, which, when connected to the carrier interface 10, has the effect of converting the deflection of the carrier 6 due to the weight (extending opposite to the Y direction due to the weight) into a spring force F perpendicular thereto (extending opposite to the Z direction) when the carrier 6 is inserted into the object manipulator 1 from above (i.e. opposite to the Y direction). Due to the spring force F, the worktable 6 moves against the Z direction toward the worktable interface 10 as described above, so that the stop mechanisms 12, 13, 16, 17 lead to the spatial positioning of the worktable 6 on the worktable interface 10. Instead of using a pressing device 23 with a mechanical force (for example, by the above-mentioned exemplary spring force F), a pressing device 23 using pneumatic force or any other form of force can also be used.

[0033] The first and third stop mechanisms 12, 13 constructed in the stage interface 10 are constructed as first cylindrical pins 12 or second cylindrical pins 13, which extend along the Y direction. Instead of using cylindrical pins 12, 13, the first and third stop mechanisms 12, 13 can also be used as linear axes, for example. The second stop mechanism 16 is constructed as a stop edge 16, and its stop surface is oriented parallel to the XY plane. The fourth stop mechanism 17 is constructed as a body, which has two stop surfaces at an angle to each other, namely a first stop surface 18 and a second stop surface 19. In the embodiment shown, the angle is 90°, but this is not restrictive. The two stop surfaces 18, 19 extend perpendicular to the paper plane, so that the second cylindrical pin 13 can cooperate with the two stop surfaces 18, 19 over a longer area. Due to the two stop surfaces 18, 19 and the straight stop edge 16 (cooperating with the two cylindrical pins 12, 13), the system is not overdetermined, that is, it is abutted in a limited manner.

[0034] Furthermore, the worktable 6 can be screwed to the worktable interface 10 by means of two clamping screws 14, 15. This is useful when the force F is exceeded, for example due to an additional force in the X direction, since a displacement and thus a change in position of the worktable 6 is thus prevented by the two clamping screws.

[0035] When this is necessary for adjustment, rotation of stage 6 relative to stage interface 10 may be performed about axes parallel to the X, Y and Z axes.

[0036] exist Figure 5 How to achieve rotation around a line parallel to the Y axis is shown in FIG. Figure 5 and Figure 4 Very similar, however, the stop element 16 can be moved linearly in the Z direction. If this movement is carried out in the Z direction, the stop edge 16 moves, for example, to the right (as indicated by the arrow). Since the second cylindrical pin 13 is fixed in position, as shown by Figure 5 As indicated by the curved arrow in FIG. 1 , the worktable 6 rotates counterclockwise relative to the worktable interface 10 about the axis defined by the second cylindrical pin 13. Rotation about this axis enables the contact edge and the horizontal rotation axis ZOR parallel to the linear axis XO or ZO (for axis designations see Figure 1 ) orientation.

[0037] exist Figure 6 and Figure 7 How to achieve rotation around an axis parallel to the X axis is shown in Figure 2 Reverse view in the Z direction from the right side of the drawing. The worktable 6 runs parallel to the X axis on a second guide rail 4b in the shape of a circular linear axis 4b. The clamping screws 14, 15 and the cylindrical pins 12, 13, which are not important for this movement, are also visible. In order to be able to carry out a linear movement of the worktable 6 in the X direction with as little friction as possible, there are two supports, namely a first support 20 on the right and a second support 21 on the left, which are each designed in the form of a carriage with a running wheel that is adjustable in height, i.e. in the Y direction, relative to the worktable 6. The height adjustment can be carried out, for example, by means of an eccentric wheel, wherein the height adjustment is of the same size on both supports 20, 21.

[0038] Figure 7 A highly schematic view of the manipulator 1 in the X direction is shown. On the left, the first guide rail 4a, which is designed as a profile rail 4a, is shown as it interacts with the worktable interface 10 and the worktable 6, while on the right, the displacement (indicated by the arrow) of the support area 9 of the worktable 6 due to the previously described height adjustment of the two supports 20, 21 by eccentric adjustment is shown. This results in a rotational movement (indicated by the curved arrow) in the counterclockwise direction about the axis formed by the first guide rail 4a.

[0039] exist Figure 8 How to achieve rotation around a line parallel to the Z axis is shown in FIG. Figure 8 Basically corresponds to Figure 6 However, now the two supports 20, 21 are no longer adjusted in height to the same extent, but only the first support 20 is adjusted in height relative to the worktable 6 (this is in contrast to the above description of Figure 6 and 7As already mentioned, only a minimal height change is involved, which has a very small overall effect. Although the second rotation is not carried out exactly around an axis parallel to the Z direction, due to the twisting of the sample stage 6, the result is that, as shown by the curved arrow, a rotation of the sample stage 6 is carried out approximately around an axis parallel to the Z direction.

[0040] Combined rotation about axes parallel to the X and Z axes (as in Figures 6 to 8 ) realizes the axis of the object stage 6 (here in Figure 1 The axis YOR) shown in FIG. 1 is parallel to the central ray, ie parallel to the orientation of the Y axis.

[0041] Reference numerals list

[0042] 1 Object Manipulator

[0043] 2 X-ray tube

[0044] 3 X-ray detectors

[0045] 4 First linear guide

[0046] 4a First guide rail, profile rail

[0047] 4b Second guide rail, linear axis

[0048] 5 Second linear guide

[0049] 5a Third rail

[0050] 5b Fourth rail

[0051] 6 Stage

[0052] 7 Accommodating recess

[0053] 8 Interface area

[0054] 9 Resting area

[0055] 10 Stage interface

[0056] 11 steps

[0057] 12 first stop mechanism, first cylindrical pin

[0058] 13 third stop mechanism, second cylindrical pin

[0059] 14 Clamping screw

[0060] 15 Clamping screw

[0061] 16 Second stop mechanism, stop edge

[0062] 17 Fourth stop mechanism

[0063] 18 First stop surface

[0064] 19 Second stop surface

[0065] 20 first support

[0066] 21 Second support

[0067] 22 Inspection Object

[0068] 23 Extrusion device

Claims

1. An object manipulator (1) for an X-ray inspection device, comprising: a stage (6) on which the test object (22) can be fixed, A first linear guide (4), the stage (6) being movable in a first direction along the first linear guide, A second linear guide (5), along which the worktable (6) can move in a second direction, wherein: The second direction has a component perpendicular to the first direction, in particular the second direction is perpendicular to the first direction, A stage interface (10) is constructed on the first linear guide (4). The loading platform (6) has an interface area (8), on which the loading platform is detachably connected to the loading platform interface (10) via a connecting device. The worktable (6) has a resting area (9), in which the worktable is arranged on the first linear guide in a positionally changeable manner relative to the first linear guide (4), and the worktable is constructed to be positionally separated from the interface area (8), in particular at the end of the worktable facing away from the interface area (8).

2. The object manipulator (1) according to claim 1, wherein: The first linear guide (4) has two parallel guide rails and / or the second linear guide (5) has two parallel guide rails, wherein the guide rails are in particular round or rectangular linear axes.

3. The object manipulator (1) according to claim 1 or 2, wherein: The connecting device has two screws, in particular clamping screws (14, 15), which cooperate with the object carrier interface (10) and the interface area (8).

4. The object manipulator (1) according to claim 1 or 2, wherein: The connecting device has a first stop mechanism (12) and a third stop mechanism (13) on the worktable interface (10), and the connecting device has a second stop mechanism (16) and a fourth stop mechanism (17) on the interface area (8), wherein the second stop mechanism (16) is pressed against the first stop mechanism (12) by means of a squeezing device (23) and the fourth stop mechanism (17) is pressed against the third stop mechanism (13).

5. The object manipulator (1) according to claim 4, wherein: The first stop mechanism (12) and the third stop mechanism (13) are respectively linear shafts or cylindrical pins, which extend substantially perpendicularly to the first direction and the second direction, and wherein the second stop mechanism (16) is a straight stop edge extending along the first direction, and wherein the fourth stop mechanism (17) is a body having a first stop surface (18) and a second stop surface (19), wherein the respective orientations of the first stop surface and the second stop surface have directional components which are not parallel to the stop edges, and wherein one of the directional components has a positive angle relative to the second direction, and the other directional component has a negative angle relative to the second direction, wherein the angle between the two orientations is in particular 90°.

6. The object manipulator (1) according to claim 5, wherein: At least one of the linear axes or one of the cylindrical pins is movable relative to the carrier interface (10) in a direction having a component in the second direction and / or the straight stop edge is movable in a direction having a component in the second direction.

7. The object manipulator (1) according to claim 4, wherein: The pressing device (23) has a spring which has a force component along the second direction, and the pressing device (23) is in particular a lateral pressure piece.

8. The object manipulator (1) according to claim 1 or 2, wherein: The object manipulator has both a connecting device according to claim 3 and a connecting device according to any one of claims 4 to 7 .

9. The object manipulator (1) according to claim 1 or 2, wherein: Two supporting bodies (20, 21), in particular rotating running wheels, are arranged on the worktable interface (10), and the supporting bodies support the movement of the worktable interface (10) together with the worktable (6) along the first direction, wherein at least one of the supporting bodies (20, 21), preferably both supporting bodies (20, 21) can be moved along a third direction, and the third direction has both a component perpendicular to the first direction and a component perpendicular to the second direction, wherein the third direction is preferably perpendicular to the first direction and the second direction.

10. The object manipulator (1) according to claim 9, wherein: At least one of the two supports (20, 21) is movable via an eccentric device.

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