Radiation emitting devices and radiation inspection equipment

Abstract

The present disclosure provides a radiation emitting device and radiation inspection equipment. The radiation emitting device includes: multiple radiation sources, each configured to output a radiation beam; and a collimator, disposed on the beam-out side of the multiple radiation sources and configured to simultaneously limit the beam shape of the radiation beams output by the multiple radiation sources. The radiation emitting device and radiation inspection equipment facilitate installation and commissioning of the radiation emitting device.

Description

Technical Field

[0001] The present disclosure relates to the technical field of radiation inspection, and in particular to a ray emitting device and radiation inspection equipment. Background Art

[0002] Radiation inspection equipment, such as X-rays, primarily utilizes the strong penetrating power of radiation and the relationship between radiation energy attenuation and equivalent atomic number to inspect objects. Radiation inspection equipment is widely used in medical, security, customs, and other fields.

[0003] According to the imaging perspective, radiation inspection equipment can be divided into single-perspective, dual-perspective, multi-perspective and CT imaging. Single-perspective mainly includes horizontal or vertical irradiation of the inspected object for imaging. Dual-perspective mainly refers to simultaneous horizontal and vertical perspectives for irradiating the inspected object for imaging. Multi-perspective mainly refers to simultaneous multiple perspectives.

[0004] For dual-view or multi-view radiation inspection equipment, its ray emitting device generally includes two or more ray sources and two or more collimators arranged in conjunction with the two or more ray sources. Summary of the Invention

[0005] The present disclosure aims to provide a ray emitting device and a radiation inspection apparatus.

[0006] A first aspect of the present disclosure provides a ray emitting device, comprising:

[0007] a plurality of radiation sources, each of the radiation sources being configured to output a radiation beam; and

[0008] A collimator is provided on the beam-out side of the plurality of ray sources and is configured to simultaneously limit the beam shapes of the ray beams output by the plurality of ray sources.

[0009] In some embodiments, the collimator includes a collimation port, and the collimation port is configured to simultaneously limit the beam shape of the ray beams output by the multiple ray sources; or, the collimator includes two or more collimation ports, the multiple ray sources are provided in a one-to-one correspondence with the two or more collimation ports, and each collimation port is configured to limit the beam shape of the ray beam output by the corresponding ray source; or

[0010] The collimator includes more than two collimation ports, the multiple ray source groups are arranged corresponding to the more than two collimation ports, and each of the collimation ports is configured to simultaneously limit the beam shape of the ray beam output by each ray source in a corresponding group of ray sources.

[0011] In some embodiments, the collimator includes two collimating plates, and the two collimating plates are matched to form the collimating port.

[0012] In some embodiments, the collimating opening is a collimating slit in a straight line shape, a broken line shape, a curved line shape, or a combination of a straight line shape and a curved line shape.

[0013] In some embodiments, an adjustment mechanism is further included, wherein the adjustment mechanism is configured to adjust and maintain the beam shapes of the ray beams output by the plurality of ray sources after adjustment.

[0014] In some embodiments, the collimator includes two collimating plates, and the adjustment mechanism adjusts the size or shape of the collimating opening by driving the position of at least one collimating plate relative to the remaining collimating plates.

[0015] In some embodiments, the adjustment mechanism includes at least one adjustment part, and at least one of the collimation plates is correspondingly provided with the adjustment part. The adjustment part is configured to change the relative position of the corresponding collimation plate relative to another collimation plate by driving the corresponding collimation plate to translate and / or rotate so as to adjust the size or shape of the collimation port.

[0016] In some embodiments,

[0017] At least one of the two collimating plates is provided with a long hole extending in a direction different from that of the collimating opening;

[0018] The ray emitting device further includes a ray source cabin, wherein the plurality of ray sources are located in the ray source cabin; and

[0019] The adjusting portion includes a first threaded connector, which is configured to match the long hole in a variably relative position and fix the collimating plate where the long hole is located on the ray source cabin.

[0020] In some embodiments, the adjustment part also includes a second threaded connector provided on the radiation source cabin body. When the first threaded connector fixes the corresponding collimation plate to the radiation source cabin body, the second threaded connector is configured so that the end face of one end of the second threaded connector presses against the edge of the collimation plate fixed by the first threaded connector away from the collimation port.

[0021] In some embodiments, the adjustment unit further comprises:

[0022] A mounting seat, fixed to the radiation source cabin and having a mounting hole, wherein the second threaded connector is inserted into the mounting hole; and

[0023] A locking nut is arranged on the outer side of the mounting seat and cooperates with the second threaded connector to lock the second threaded connector on the mounting seat.

[0024] In some embodiments, the adjusting portion includes:

[0025] a stepping motor, drivingly connected to the corresponding collimating plate; and

[0026] The controller is connected to the stepper motor signal, and the stepper motor is configured to operate according to the control instruction issued by the controller.

[0027] In some embodiments, the adjustment portion further includes a transmission component, which is connected between the stepper motor and the corresponding collimation plate and is configured to convert the rotation of the stepper motor into the translation of the collimation plate to change the relative position of the corresponding collimation plate relative to the other collimation plate.

[0028] In some embodiments,

[0029] The two collimating plates are respectively provided with the adjusting parts, and / or

[0030] At least one of the collimating plates is correspondingly provided with two or more of the adjusting parts.

[0031] A second aspect of the present disclosure provides a radiation inspection device, the aforementioned ray emitting device.

[0032] The radiation emitting device provided in this disclosure includes multiple radiation sources and a collimator corresponding to the multiple radiation sources. The collimator can simultaneously limit the shape of the radiation beams emitted by the multiple radiation sources, facilitating the installation and commissioning of the radiation emitting device. The radiation inspection equipment provided in this disclosure has the same advantages as the radiation emitting device provided in this disclosure.

[0033] Other features and advantages of the present disclosure will become apparent from the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings described herein are used to provide a further understanding of the present disclosure and constitute a part of this application. The illustrative embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation of the present disclosure. In the drawings:

[0035] Figure 1 This is a schematic diagram of the principle structure of a ray emitting device at one angle in some embodiments of the present disclosure.

[0036] Figure 2 for Figure 1 A schematic diagram of the principle structure of the ray emitting device of the illustrated embodiment from another angle.

[0037] Figure 3 This is a schematic diagram of the principle structure of a ray emitting device at one angle in some embodiments of the present disclosure.

[0038] Figure 4 for Figure 3 A schematic diagram of the principle structure of the ray emitting device of the illustrated embodiment from another angle.

[0039] Figure 5 This is a schematic diagram of the principle structure of a ray emitting device at one angle in some embodiments of the present disclosure (the ray source is not shown).

[0040] Figure 6 This is a schematic diagram of the principle structure of a ray emitting device at one angle in some embodiments of the present disclosure (the ray source is not shown).

[0041] Figure 7 This is a schematic diagram of the principle structure of a ray emitting device at one angle in some embodiments of the present disclosure.

[0042] Figure 8 This is a schematic diagram of the principle structure of a ray emitting device at one angle in some embodiments of the present disclosure. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present disclosure and its application or use. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure.

[0044] Unless otherwise specifically stated, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present disclosure. At the same time, it should be understood that, for ease of description, the sizes or shapes of the various parts shown in the drawings are not drawn according to actual proportional relationships. The techniques, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as being merely exemplary and not as limitations. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0045] In the description of the present disclosure, it should be understood that the use of words such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above words have no special meaning and therefore cannot be understood as limiting the scope of protection of the present disclosure.

[0046] In the description of the present disclosure, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present disclosure and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present disclosure; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0047] The “plurality” referred to in the present disclosure means “two” or “more than two”.

[0048] like Figures 1 to 4 As shown, an embodiment of the present disclosure provides a radiation emitting device. The radiation emitting device includes multiple radiation sources 1 and a collimator 2. Each radiation source 1 is configured to output a radiation beam. The collimator 2 is disposed on the beam-out side of the multiple radiation sources 1 and is configured to simultaneously limit the beam shape of the radiation beams output by the multiple radiation sources 1.

[0049] In some embodiments, as Figures 1 to 6 As shown, the collimator 2 may include a collimation port 22 , and the collimation port 22 is configured to simultaneously limit the beam shapes of the ray beams output by the plurality of ray sources 1 .

[0050] In some embodiments, as Figure 7 As shown, the collimator may include more than two collimation ports 22 , and the multiple ray sources 1 are provided in one-to-one correspondence with the more than two collimation ports 22 . Each collimation port 22 is configured to limit the beam shape of the ray beam output by the corresponding ray source 1 .

[0051] In some embodiments, as Figure 8 As shown, the collimator may include more than two collimation ports 22, and multiple ray sources 1 are grouped and set corresponding to the two or more collimation ports 22. Each collimation port 22 is configured to limit the beam shape of the ray beam output by each ray source 1 in a corresponding group of ray sources 1, or multiple ray sources 1 are grouped and set corresponding to the two or more collimation ports 22.

[0052] The ray emitting device of the embodiment of the present disclosure includes multiple ray sources and a collimator corresponding to the multiple ray sources, so that the collimators corresponding to the multiple ray sources are integrated. The collimator can simultaneously limit the shape of the ray beams emitted by multiple ray sources, which is beneficial to the installation and debugging of the ray emitting device.

[0053] The ray source 1 may be a ray source that generates X-rays, gamma-rays or neutron rays, for example, an accelerator or an X-ray tube.

[0054] like Figures 1 to 4 As shown, the collimator 2 includes two collimating plates 21 , and a gap between the two collimating plates 21 forms a collimating opening 22 .

[0055] In different embodiments, the collimating plate can be set to a corresponding shape and structure according to the arrangement of the ray source and the beam output requirements. For example, the collimating plate can be a flat plate, a folded plate, a curved plate, or a combination of a flat plate and a curved plate.

[0056] like Figures 1 to 3 As shown, in some embodiments, the collimation opening 22 is a collimation slit in the shape of a broken line. Figure 1 and Figure 2 The collimating slits in the same plane as shown can also be Figure 3 and Figure 4 The embodiment shown has a collimating slit in the shape of a broken line in a three-dimensional space.

[0057] In some embodiments not shown, the collimation port can be set to a corresponding shape and structure according to the arrangement of the ray source and the beam output requirements. For example, the collimation port can also be a collimation slit in a straight line, a curved line, or a combination of straight lines and curved lines.

[0058] Furthermore, when the collimation opening is a collimation slit, the cross-sectional shape or cross-sectional size or shape of the collimation slit may be always the same along the extension direction of the collimation slit, for example, Figures 1 to 6 The embodiment shown can be set in this manner.

[0059] In some embodiments (not shown), the cross-sectional shape, size, or shape of the collimating slit may vary along its extension direction. For example, the cross-sectional shape of a local portion of the collimating slit, such as the beam exit position of the corresponding radiation source, may be enlarged or reduced relative to the cross-sectional shape of other portions. The shape of the enlarged or reduced portion may be configured as desired, such as square, elliptical, triangular, circular, or the like.

[0060] like Figure 5 As shown, in order to obtain a suitable beam shape of the radiation beam, in some embodiments, the radiation emitting device includes an adjustment mechanism configured to adjust and maintain the size or shape of the collimation port 22 after adjustment to adjust the beam shape of the radiation beams output by the multiple radiation sources 1 .

[0061] like Figures 1 to 6 As shown, in some embodiments, the collimator 2 includes two collimating plates 21 spaced apart and arranged side by side, and a collimating opening 22 is formed between the two collimating plates 21 .

[0062] The adjustment mechanism includes at least one adjustment portion 4. At least one collimating plate 21 is provided with an adjustment portion 4. The adjustment portion 4 is configured to adjust the size or shape of the collimating opening 22 by changing the relative position of the corresponding collimating plate 21 relative to the other collimating plate 21.

[0063] like Figure 5 As shown, in some embodiments, at least one of the two collimating plates 21 is provided with an elongated hole 211 extending in a direction different from that of the collimating opening 22. The radiation emitting device further includes a radiation source cabin 3, in which a plurality of radiation sources 1 are located. The adjusting portion 4 includes a first threaded connector 41, which is configured to variably engage with the elongated hole 211 relative to the collimating plate 21, and secure the collimating plate 21, in which the elongated hole 211 is located, to the radiation source cabin 3.

[0064] The first threaded connector 41 cooperates with the elongated hole 211 to adjust the size or shape of the collimator opening 22 and maintain the adjusted size or shape. Adjusting the position of the first threaded connector 41 in conjunction with the elongated hole 211 allows adjustment of the collimator opening 22. Once the first threaded connector 41 is secured, the adjusted size or shape of the collimator opening 22 is maintained. The first threaded connector 41 is, for example, a screw.

[0065] like Figure 5 As shown, in some embodiments, the adjustment part 4 also includes a second threaded connector 42 arranged on the radiation source cabin body. When the first threaded connector 41 fixes the corresponding collimation plate 21 to the radiation source cabin body 3, the second threaded connector 42 is configured so that the end face of one end is pressed against the edge of the collimation plate 21 fixed by the first threaded connector 41 away from the collimation port 22.

[0066] The second threaded connector 42 can cooperate with the first threaded connector 42 to jointly maintain the position of the corresponding collimating plate 21. Therefore, after the size or shape of the collimating port 22 is adjusted, it is helpful to maintain the size or shape of the collimating port 22, thereby helping to maintain the beam shape of the adjusted ray beam.

[0067] like Figure 5 As shown, in some embodiments, the adjustment unit 4 further includes a mounting base 43 and a locking nut 44. The mounting base 43 is fixed to the radiation source cabin 3 and has a mounting hole, through which the second threaded connector 42 is inserted. The locking nut 44 is disposed outside the mounting base 43 and cooperates with the second threaded connector 42 to lock the second threaded connector 42 to the mounting base 43.

[0068] The mounting hole can be a screw hole or a plain hole that mates with the second threaded connector 42. If the mounting hole is a screw hole, the locking nut 44 can be disposed on a single side of the mounting base 43, or two or more locking nuts 44 can be disposed on both sides of the mounting base 43. If the mounting hole is a plain hole, the two or more locking nuts 44 are disposed on both sides of the mounting base 43. The second threaded connector 42 is, for example, a screw.

[0069] Figure 5 In the embodiment, a locking nut 44 is provided on each side of the mounting seat 43 for locking the second threaded connection member 42 .

[0070] In some embodiments, each of the two collimating plates 21 is provided with an adjustment portion 4. In some embodiments, at least one collimating plate 21 is provided with two or more adjustment portions 4. For example, an equal number of adjustment portions 4 may be symmetrically provided on the two collimating plates 21. Properly determining the number of adjustment portions 4 and their functional relationship with the collimating plates 21 allows for more flexible and accurate adjustment of the size or shape of the collimating opening 22.

[0071] When adjusting the collimation opening 22, the first threaded connector 41 and the second threaded connector 42 can be loosened first to adjust the size or shape of the collimation opening 22. A feeler gauge or other tool can be used to adjust the size or shape of the collimation opening 22 to the appropriate size or shape. After the size or shape of the collimation opening 22 is adjusted, the first threaded connector 41 is tightened, and then the end face of the second threaded connector 42 is placed against the corresponding collimation plate 211. The second threaded connector 42 is then tightened with the lock nut 44.

[0072] The adjustment mechanism in the above embodiment is a manual adjustment device. In some embodiments, Figure 6 As shown, the adjustment mechanism can also be an automatic adjustment device. For example, the adjustment portion 4 of the adjustment mechanism can include a stepper motor 45 and a corresponding transmission component 46, and a controller 5 connected to the stepper motor 45 via a signal. The stepper motor 45 is connected to the collimation plate 21 through the transmission component 46, and the stepper motor 45 drives the collimation plate 21 to adjust the size or shape of the collimation aperture. The stepper motor 45 is configured to operate according to control commands issued by the controller 5.

[0073] The transmission component 46 may include, for example, a screw-nut transmission mechanism, a connecting rod mechanism, or other transmission mechanism that can convert the rotation of the stepper motor into the translational motion of the collimator plates 21. By controlling the rotation angle of the stepper motor 45 via the controller 5, the movement of the corresponding collimator plates 21 can be controlled, thereby adjusting the spacing between the two collimator plates 21 and adjusting the size or shape of the collimator opening 22.

[0074] Figure 6In the illustrated embodiment, the transmission component 46 is a screw-nut transmission mechanism comprising a screw 461 and a nut 462. The screw 461 is connected to the collimation plate 21, and the nut 462 is connected to the output shaft of the stepper motor 45. The rotation of the stepper motor 45 drives the nut 464 to rotate. The nut 462 engages with the screw 461, driving the screw 461 to move, thereby moving the collimation plate 21 and adjusting the width of the collimation opening 22.

[0075] Among them, the aforementioned controller 5 can be a general-purpose processor, a programmable logic controller (PLC), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware component or any appropriate combination thereof for performing the functions described in the present invention.

[0076] above Figures 1 to 6 In the illustrated embodiment, the ray emitting device of the present disclosure is described by taking as an example that two collimating plates are opposed to each other to form a collimating gap, and the two collimating plates are relatively translated to change the size of the gap.

[0077] In some embodiments, as long as the structure of the collimating plate is properly set, the size or shape of the collimating opening can be adjusted by other means.

[0078] For example, Figure 7 and Figure 8 Based on the embodiment shown, the two collimation plates can be offset up and down, and an adjustment mechanism can be provided (refer to the aforementioned embodiment for setting the adjustment mechanism). Then, the size or shape of multiple collimation openings can be adjusted by changing the degree of overlap of the two collimation plates.

[0079] In the aforementioned embodiments, the collimation plates are flat plates. In some embodiments (not shown), the collimation plates may be curved plates, such as cylindrical plates. In this case, the size or shape of the collimation openings can also be adjusted by relative rotation of the two curved plates. If a stepper motor is used as the driving device for the collimation plates, a transmission mechanism between the stepper motor and the collimation plates may not be necessary.

[0080] In some embodiments not shown in the figures, the size or shape of the collimating slit can be changed by changing the angle between the two collimating plates.

[0081] Compared to related art ray-emitting devices that have a one-to-one correspondence between ray sources and collimators, the ray-emitting device of the present disclosure includes multiple ray sources and a single collimator corresponding to each of the multiple ray sources. This single collimator can simultaneously limit the beam shape of the ray beams emitted by multiple ray sources, enabling simultaneous beam-limiting and collimation of multiple ray sources. Furthermore, the shape of the ray beams emitted by each ray source, or some of the ray sources, can be adjusted simultaneously by adjusting the size or shape of the collimator's aperture.

[0082] The disclosed embodiments further provide a radiation inspection device comprising the aforementioned radiation emitting device. This radiation inspection device possesses the advantages of the aforementioned radiation emitting device. The radiation inspection device employing this radiation emitting device is easily assembled and adjusted, facilitating synchronous adjustment of the beam output range of the entire radiation emitting device to achieve multi-angle imaging, ensuring concentrated and accurate beam output energy, and thus ensuring high-quality images.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure and are not intended to limit them. Although the present disclosure has been described in detail with reference to preferred embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present disclosure can still be modified or some technical features can be replaced by equivalents, which should all be included in the scope of the technical solutions claimed for protection in the present disclosure.

Claims

1. A multi-view radiation inspection device, comprising a ray emitting device, characterized in that: The ray emitting device comprises: A plurality of ray sources (1), each of the ray sources (1) being configured to output a ray beam; a collimator (2) disposed on the beam-out side of the plurality of ray sources (1), comprising a collimation port (22), wherein the collimation port (22) is configured to simultaneously limit the beam shape of the ray beams output by the plurality of ray sources (1) for achieving multi-view imaging, wherein the collimation port (22) is a collimation slit in a zigzag shape, a curved shape, or a combination of a straight line and a curved shape; and An adjustment mechanism is configured to adjust and maintain the beam shape of the ray beams output by the plurality of ray sources (1) after adjustment.

2. The radiation inspection device according to claim 1, characterized in that The collimator (2) comprises two collimating plates (21), and the two collimating plates (21) are matched in shape to form the collimating opening (22).

3. The radiation inspection device according to claim 1, wherein: The collimator comprises two collimating plates (21), and the adjustment mechanism adjusts the size or shape of the collimating opening (22) by driving the position of at least one collimating plate (21) relative to the remaining collimating plates (21).

4. The radiation inspection device according to claim 3, characterized in that: The adjustment mechanism comprises at least one adjustment portion (4), and at least one of the collimating plates (21) is correspondingly provided with the adjustment portion (4). The adjustment portion (4) is configured to change the relative position of the corresponding collimating plate (21) relative to another collimating plate (21) by driving the corresponding collimating plate (21) to translate and / or rotate, thereby adjusting the size or shape of the collimating port (22).

5. The radiation inspection device according to claim 4, characterized in that: At least one of the two alignment plates (21) is provided with a long hole (211) extending in a direction different from that of the alignment opening (22); The ray emitting device further comprises a ray source cabin (3), wherein the plurality of ray sources (1) are located in the ray source cabin (3); and The adjusting portion (4) comprises a first threaded connection member (41), the first threaded connection member (41) being configured to variably cooperate with the long hole (211) in relative position and to fix the collimating plate (21) where the long hole (211) is located to the ray source cabin (3).

6. The radiation inspection device according to claim 5, characterized in that: The adjusting portion (4) further comprises a second threaded connector (42) provided on the radiation source cabin body, wherein when the first threaded connector (41) fixes the corresponding collimating plate (21) to the radiation source cabin body (3), the second threaded connector (42) is configured such that an end surface of one end of the second threaded connector (42) presses against an edge of the collimating plate (21) fixed by the first threaded connector (41) away from the collimating opening (22).

7. The radiation inspection device according to claim 6, characterized in that: The regulating part (4) further includes: A mounting seat (43) is fixed to the radiation source cabin (3) and has a mounting hole, and the second threaded connection member (42) is inserted into the mounting hole; and A locking nut (44) is arranged on the outside of the mounting seat (43) and cooperates with the second threaded connector (42) to lock the second threaded connector (42) on the mounting seat (43).

8. The radiation inspection device according to claim 4, characterized in that: The regulating part (4) comprises: a stepping motor (45) drivingly connected to the corresponding collimating plate (21); and The controller (5) is connected to the stepper motor (45) via a signal, and the stepper motor (45) is configured to operate according to a control instruction issued by the controller (5).

9. The radiation inspection device according to claim 8, characterized in that: The adjusting portion (4) further includes a transmission component (46), which is connected between the stepping motor (45) and the corresponding collimating plate (21) and is configured to convert the rotation of the stepping motor (45) into the translation of the collimating plate (21) to change the relative position of the corresponding collimating plate (21) relative to another collimating plate (21).

10. The radiation inspection device according to claim 4, characterized in that: The two collimating plates (21) are respectively provided with the adjusting parts (4), and / or At least one of the collimating plates (21) is correspondingly provided with two or more of the adjusting parts (4).

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