CT device

Abstract

Provided is a CT device, being related to the technical field of radiation scanning. The CT device comprises a rack; multiple supporting apparatuses arranged on the rack; a rotatable portion, the rotatable portion being able to rotate around a rotation axis when driven by a driving wheel, and the rotatable portion being jointly supported by the multiple supporting apparatuses during the rotation process; a scanning apparatus arranged on the rotatable portion, the scanning apparatus being used for scanning an object to be examined; an axial limiting mechanism comprising a first pressing roller set and a second pressing roller set, wherein the first pressing roller set and the second pressing roller set are separately arranged on the end faces on two sides of the rotatable portion in the direction of the rotation axis; the first pressing roller set and the second pressing roller set each comprise n pressing rollers, n being an integer larger than 3, and at least a part of the outer circumferential face of each pressing roller is in contact with the end face of the rotatable portion so as to limit the movement of the rotatable portion in the direction of the rotation axis.

Description

CT equipment

[0001] This application claims priority to Chinese patent application No. 202311837728.5 filed on December 28, 2023, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present disclosure relates to the technical field of radiation inspection, and more particularly, to a CT device. Background Art

[0003] CT technology plays a vital role in security inspections because it can eliminate the effects of overlapping objects. CT equipment is also widely used in technical fields such as object inspection. CT equipment can inspect not only smaller items like luggage and air boxes, but also larger items like containers and vehicles.

[0004] In related technologies, CT equipment uses a slip ring mechanism to acquire projection data at different angles through the rotation of the X-ray machine and detector. Reconstruction methods generate tomographic images, thereby revealing internal information about the inspected baggage item. Combined with dual-energy or multi-energy imaging technology, current baggage inspection equipment can reconstruct the atomic number and electron density of the inspected material, enabling identification of the substance type. This has proven effective in detecting explosives and hazardous materials.

[0005] For example, in related technologies, when the rotatable part of a CT device is supported by a supporting device, the rotatable part generates a displacement along the direction of the rotation axis during rotation. When the displacement is large and the rotation speed of the rotatable part is fast, the CT device vibrates, affecting the imaging accuracy of the CT device.

[0006] The above information disclosed in this section is only for understanding of the background of the disclosed concept of the present disclosure and therefore the above information may contain information that does not constitute the relevant art. Summary of the Invention

[0007] One aspect of the present disclosure provides a CT device, comprising: a gantry; a supporting device arranged on the gantry, the supporting device comprising a plurality of rotating wheels, wherein at least one rotating wheel of the supporting device serves as a driving wheel; a rotatable part, the rotatable part being capable of rotating around a rotation axis under the drive of the driving wheel, and during the rotation of the rotatable part, the rotatable part is jointly supported by the plurality of supporting devices; a scanning device, arranged on the rotatable part, the scanning device being used to scan an object to be inspected; an axial limiting mechanism, comprising a first pressure wheel group and a second pressure wheel group, wherein the first pressure wheel group and the second pressure wheel group are respectively arranged on both side end surfaces of the rotatable part along the direction of the rotation axis, wherein each of the first pressure wheel group and the second pressure wheel group comprises n pressure wheels, where n is an integer greater than 3, and at least a portion of the outer circumferential surface of any pressure wheel contacts the end surface of the rotatable part, so as to limit the movement of the rotatable part along the direction of the rotation axis.

[0008] In some exemplary embodiments of the present disclosure, one of the first pressure wheel group and the second pressure wheel group includes an eccentric pressure wheel group, and the other of the first pressure wheel group and the second pressure wheel group includes an axial pressure wheel group; or, both the first pressure wheel group and the second pressure wheel group are axial pressure wheel groups; or, both the first pressure wheel group and the second pressure wheel group are eccentric pressure wheel groups.

[0009] In some exemplary embodiments of the present disclosure, in a direction parallel to the rotation axis, the rotatable part sequentially includes a first rotating track, a rotatable part body and a second rotating track; in a direction parallel to the rotation axis, the first pressure wheel group is arranged on a side of the first rotating track away from the rotatable part body, and the second pressure wheel group is arranged on a side of the second rotating track away from the rotatable part body.

[0010] In some exemplary embodiments of the present disclosure, the axial pressure wheel group and the eccentric pressure wheel group both include: a fixed seat, a connecting rod, a first bearing, a rotating shaft, a wheel seat, a wheel axle, a second bearing, a first pressure wheel element and a second pressure wheel element, the fixed seat is fixedly connected to the frame, the outer ring of the first bearing is fixed on the fixed seat, the rotating shaft is fixedly connected to the inner ring of the first bearing, the connecting rod is arranged on the rotating shaft, the wheel seat is arranged on both ends of the connecting rod, at each end of the connecting rod, the wheel axle is fixed on the wheel seat, the first pressure wheel element is arranged on the wheel axle through the second bearing, and the second pressure wheel element is arranged on the wheel axle through the second bearing.

[0011] In some exemplary embodiments of the present disclosure, the first pressure wheel element and the second pressure wheel element are symmetrically arranged on the connecting rod with respect to the center of the rotatable portion.

[0012] In some exemplary embodiments of the present disclosure, the fixing seat is symmetrically provided with two screw holes on both sides of the center of the rotatable portion, and the fixing seat is fixedly connected to the frame by mounting bolts installed in the two screw holes.

[0013] In some exemplary embodiments of the present disclosure, in the axial pressure wheel assembly, each of the first pressure wheel element and the second pressure wheel element includes at least two axial pressure wheels stacked sequentially along the wheel axis direction.

[0014] In some exemplary embodiments of the present disclosure, in the axial pressure wheel group, the central axes of the first pressure wheel element and the second pressure wheel element coincide with the central axis of the wheel axle, the first pressure wheel element and the second pressure wheel element rotate on the wheel axle, and the minimum distance a between at least a portion of the outer peripheral surface of any axial pressure wheel and the end face of any rotating track along the direction of the rotation axis remains unchanged.

[0015] In some exemplary embodiments of the present disclosure, in the eccentric pressure wheel assembly, each of the first pressure wheel element and the second pressure wheel element includes at least two eccentric pressure wheels stacked sequentially along the wheel axis direction.

[0016] In some exemplary embodiments of the present disclosure, in the eccentric pressure wheel group, the wheel axle is an eccentric shaft, the central axes of the first pressure wheel element and the second pressure wheel element do not coincide with the central axis of the wheel axle, the first pressure wheel element and the second pressure wheel element rotate eccentrically on the wheel axle, and the minimum distance b between at least a portion of the outer peripheral surface of any eccentric pressure wheel and the end face of any rotating track along the direction of the rotation axis is variable.

[0017] In some exemplary embodiments of the present disclosure, the minimum distance a and the minimum distance b jointly adjust the movement of the rotatable part along the direction of the rotation axis.

[0018] In some exemplary embodiments of the present disclosure, in the eccentric pressure wheel assembly, the rotating shaft is set as an eccentric rotating shaft, the rotating shaft is fixed to the inner ring of the first bearing, the inner ring of the first bearing cooperates with the eccentric rotating shaft to make the connecting rod rotate eccentrically, and each of the first pressure wheel element and the second pressure wheel element includes at least two axial pressure wheels stacked in sequence along the wheel axle direction.

[0019] In some exemplary embodiments of the present disclosure, the eccentric pressure wheel assembly further includes: the fixing seat has long holes symmetrically preset along the direction of the rotation axis on both sides of the center of the rotatable part, and the fixing seat can move along the long holes.

[0020] In some exemplary embodiments of the present disclosure, any one of the first piezo wheel element and the second piezo wheel element has a cylindrical surface.

[0021] Additional aspects and advantages of the present disclosure will be given in part in the description that follows and, in part, will be obvious from the description that follows, or will be learned through practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to better understand the present disclosure, the present disclosure will be described in detail according to the following drawings:

[0023] FIG1 is a front view of a CT apparatus according to some exemplary embodiments of the present disclosure;

[0024] FIG2 is a side view of a CT apparatus according to some exemplary embodiments of the present disclosure;

[0025] 3 is a front view of a rotatable portion of a CT apparatus according to some exemplary embodiments of the present disclosure;

[0026] FIG4 is a side view of a rotatable portion of a CT apparatus according to some exemplary embodiments of the present disclosure;

[0027] FIG5A is a schematic structural diagram of an axial compression wheel assembly of a CT device according to some exemplary embodiments of the present disclosure;

[0028] FIG5B is a schematic structural diagram of an axial pressure wheel assembly of a CT device sliced ​​along the AA direction along the central axis of a connecting rod according to some exemplary embodiments of the present disclosure;

[0029] FIG5C is a schematic diagram of a partial structure of a pressure wheel element in an axial pressure wheel assembly of a CT device according to some exemplary embodiments of the present disclosure;

[0030] FIG6A is a schematic structural diagram of an eccentric pressure wheel assembly of a CT device according to some exemplary embodiments of the present disclosure;

[0031] FIG6B is a schematic diagram of a partial structure of a pressure wheel element in an eccentric pressure wheel assembly of a CT device according to some exemplary embodiments of the present disclosure;

[0032] FIG7 is a partial structural diagram of the connection between a fixing seat and a gantry of another eccentric pressure wheel assembly of a CT device according to some exemplary embodiments of the present disclosure;

[0033] FIG8 is a schematic structural diagram of a magnetic device of a CT apparatus according to another exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0034] Specific embodiments of the present disclosure will be described in detail below. It should be noted that the embodiments described herein are intended to be illustrative only and are not intended to limit the present disclosure. In the following description, a large number of specific details are set forth to provide a thorough understanding of the present disclosure. However, it will be apparent to those skilled in the art that these specific details are not necessarily required to practice the present disclosure. In other examples, known structures, materials, or methods are not specifically described to avoid obscuring the present disclosure.

[0035] Throughout this specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the present disclosure. Thus, appearances of the phrases "in one embodiment," "in an embodiment," "an example," or "an example" in various places throughout this specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, or characteristics may be combined in any suitable combinations and / or subcombinations in one or more embodiments or examples. Furthermore, one of ordinary skill in the art will understand that the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0036] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise," "include," etc. used herein indicate the presence of features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0037] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0038] In related technologies, when the rotatable part of a CT device is supported by a supporting device, the rotatable part generates a displacement along the axis of rotation during rotation. When the displacement is large and the rotation speed of the rotatable part is fast, the CT device vibrates, affecting the imaging accuracy of the CT device.

[0039] To solve this problem, the relevant distributed bearing CT equipment uses two sets of fixed axial pressure wheels as axial constraints for the imaging system under high-speed rotation. The relevant axial limiting structure adopts a fixed structure. In order to ensure that both sets of pressure wheels can contact the end face of the imaging system, high machining accuracy is required. For example, the flatness of the end face of the imaging system, the position of the radial support wheel, the cylindricity of the axial support wheel, etc. By controlling the above parameters, although the contact between the wheel and the rail can be improved, the manufacturing cost is increased, and in most cases it is still not possible to ensure that the two wheel sets are in contact with the end face of the imaging system at the same time. The axial pressure wheel and the end face of the imaging system are in single-point contact. The single-point contact of the end face of the imaging system under high-speed rotation causes the following problems: the position of the rotation center changes, exacerbating the shaking; the single-point contact causes the wheels of polymer materials to wear faster.

[0040] In view of this, an embodiment of the present disclosure provides a CT device, wherein the device includes: a frame; a supporting device arranged on the frame, the supporting device including a plurality of rotating wheels, wherein at least one rotating wheel of the supporting device serves as a driving wheel; a rotatable part, the rotatable part being capable of rotating around a rotation axis under the drive of the driving wheel, and during the rotation of the rotatable part, the rotatable part is jointly supported by the plurality of supporting devices; a scanning device, arranged on the rotatable part, the scanning device being used to scan an object to be inspected; an axial limiting mechanism, including a first pressure wheel group and a second pressure wheel group, the two pressure wheel groups, the first pressure wheel group and the second pressure wheel group being respectively arranged on both side end surfaces of the rotatable part along the direction of the rotation axis, wherein each of the first pressure wheel group and the second pressure wheel group includes n pressure wheels, n is an integer greater than 3, and at least a portion of the outer peripheral surface of any pressure wheel contacts the end surface of the rotatable part, for limiting the movement of the rotatable part along the direction of the rotation axis.

[0041] During the high-speed rotation and imaging process of the rotatable portion, displacement occurs along the rotation axis. Multiple pressure rollers in the first and second pressure roller groups, which are respectively arranged on the end surfaces of both sides of the rotatable portion, form multi-point contact with the rotating track in the rotatable portion. It should be noted that to avoid the problem of faster wear of the pressure rollers caused by single-point contact, each of the first and second pressure roller groups includes at least three or more pressure rollers. At this time, the first and second pressure roller groups can jointly and adaptively adjust the displacement of the rotatable portion to limit the shaking of the rotatable portion.

[0042] The disclosed embodiments effectively ensure that both sides of the axial end surface of the rotatable portion can form multiple points of contact with the multiple pressure rollers in the pressure roller assembly, reducing wear on individual pressure rollers while also helping to reduce operating noise. Furthermore, the positional stability of the rotatable portion is ensured, ensuring accurate CT imaging and extending the life of the device.

[0043] FIG1 is a front view of a CT device according to some exemplary embodiments of the present disclosure. FIG2 is a side view of a CT device according to some exemplary embodiments of the present disclosure. FIG3 is a front view of a rotatable portion of a CT device according to some exemplary embodiments of the present disclosure. FIG4 is a side view of a rotatable portion of a CT device according to some exemplary embodiments of the present disclosure.

[0044] The CT device according to the embodiment of the present disclosure will be described in detail below with reference to FIG. 1 to FIG. 4 .

[0045] As shown in FIG. 1 to FIG. 4 , the CT device 100 includes a gantry 110 , a supporting device 1 , a rotatable portion 2 , a scanning device 3 , and an axial limiting mechanism, including a first pressure wheel assembly 4 and a second pressure wheel assembly 5 .

[0046] The gantry 110 is used to support the CT apparatus 100. A support device 1 is disposed on the gantry 110. Multiple support devices 1 may be provided, for example, two support devices 1 may be disposed opposite each other on a first side of the gantry near the bottom, and two support devices 1 may be disposed opposite each other on a second side of the gantry near the bottom, opposite the first side. The support devices 1 support the rotatable portion 2.

[0047] The support device 1 includes a plurality of rotatable wheels 11, wherein at least one rotatable wheel 11 of at least one support device 1 serves as a driving wheel. For example, as shown in FIG1 , one rotatable wheel 11 of the support device 1 is connected to a driving motor and serves as a driving wheel.

[0048] The rotatable part 2 can rotate around the rotation axis AX1 under the drive of the driving wheel. During the rotation of the rotatable part 2 , the rotatable part 2 is supported by the plurality of supporting devices 1 .

[0049] As shown in Figures 3 and 4 , the scanning device 3 includes a radiation source 31 and a detector 32. Both the radiation source 31 and the detector 32 are disposed on the rotatable portion 2, and are arranged radially opposite each other along the rotatable portion 2. For example, the radiation source 31 is disposed on one side of the rotatable portion, and the detector 32 is disposed on a second side opposite the first side. The centers of gravity of the radiation source 31 and the detector 32 are located on the rotation axis AX1, thereby ensuring that the radiation source 31 and the detector 32 do not vibrate when the rotatable portion rotates with them.

[0050] As shown in Figure 2, the rotatable portion 2 includes, in order, a first rotatable track 21, a rotatable portion body 22, and a second rotatable track 21', parallel to the rotation axis AX1. The rotatable portion body 22 is sandwiched between the two rotatable tracks, and the scanning device 3 is disposed on the rotatable portion body 22. A first pressure roller assembly 4 and a second pressure roller assembly 5 are respectively disposed on the end surfaces of the rotatable portion 2, parallel to the rotation axis AX1.

[0051] When the rotatable part 2 of the CT device is supported by multiple supporting devices 1, the rotatable part 2 can rotate around the rotation axis under the drive of the driving wheel. During the high-speed rotation imaging process of the rotatable part 2, the rotatable part 2 will produce displacement along the rotation axis, and the CT device will vibrate.

[0052] At this point, the multiple pressure rollers on the first pressure roller assembly 4 contact the first rotation track 21 of the rotatable portion 2, thereby restricting the movement of the rotatable portion 2 in the first direction D1. The multiple pressure rollers on the second pressure roller assembly 5 contact the second rotation track 21' of the rotatable portion 2, thereby restricting the movement of the rotatable portion 2 in the second direction D2. As shown in Figure 2, the first direction D1 and the second direction D2 are both parallel to the rotation axis AX1 and opposite to each other. This ensures that the rotatable portion 2 remains stable during high-speed rotation and reduces shaking.

[0053] In some exemplary embodiments of the present disclosure, one of the first and second pressure wheel groups includes an eccentric pressure wheel group, and the other includes an axial pressure wheel group. For example, the first pressure wheel group 4 is an eccentric pressure wheel group, and the second pressure wheel group 5 is an axial pressure wheel group, or the first pressure wheel group 4 is an axial pressure wheel group, and the second pressure wheel group 5 is an eccentric pressure wheel group.

[0054] At this time, the layout positions of the two groups of pressure wheel groups are, for example, as shown in Figure 2, in the direction parallel to the rotation axis AX1, the first pressure wheel group 4 (for example, the axial pressure wheel group) is arranged on the side of the first rotating track 21 away from the rotatable part body 22, and the second pressure wheel group 5 (for example, the eccentric pressure wheel group) is arranged on the side of the second rotating track 21' away from the rotatable part body 22.

[0055] In other embodiments, the first pressing wheel group and the second pressing wheel group may both be eccentric pressing wheel groups, or both be axial pressing wheel groups.

[0056] 5A to 6B , an embodiment of the present disclosure in which a group of axial pressure wheel groups and a group of eccentric pressure wheel groups are respectively arranged on both side end surfaces of the rotatable part of the CT device is described in detail.

[0057] Figure 5A is a schematic diagram of the structure of an axial pressure wheel assembly of a CT device according to some exemplary embodiments of the present disclosure. Figure 5B is a schematic diagram of the structure of an axial pressure wheel assembly of a CT device according to some exemplary embodiments of the present disclosure, taken along the connecting rod center axis in the AA direction. Figure 5C is a schematic diagram of the partial structure of a pressure wheel element in the axial pressure wheel assembly of a CT device according to some exemplary embodiments of the present disclosure.

[0058] As shown in Figures 5A to 5C, the first pressure wheel group 4 (for example, the axial pressure wheel group) includes: a fixed seat 221, a connecting rod 222, a first bearing 223, a rotating shaft 224, a wheel seat 225, a wheel axle 226, a second bearing 227, a first pressure wheel element 228 and a second pressure wheel element 229.

[0059] The fixing seat 221 is fixedly connected to the frame 110 . The outer ring of the first bearing 223 is fixed on the fixing seat 221 . The rotating shaft 224 is fixed on the inner ring of the first bearing 223 . The connecting rod 222 is disposed on the rotating shaft 224 .

[0060] The wheel seat 225 is set on both ends of the connecting rod 222. At each end of the connecting rod 222, the wheel axle 226 is fixed on the wheel seat 225, the first pressure wheel element 228 is set on the wheel axle 226 through the second bearing 227, and the second pressure wheel element 229 is set on the wheel axle 226 through the second bearing 227.

[0061] During the rotation of the rotatable part, when the rotatable part produces a displacement along the direction of the rotation axis, the rotating track in the rotatable part will contact the first pressure wheel element in the axial pressure wheel group and the axial pressure wheel on the second pressure wheel element and generate thrust, so that the first pressure wheel element and the second pressure wheel element will rotate around the central axis of the connecting rod on a plane parallel to the rotation axis, so as to adaptively adjust the displacement of the rotatable part and limit the shaking of the rotatable part.

[0062] 5A , the first pressure wheel element 228 and the second pressure wheel element 229 are symmetrically arranged on the connecting rod about the center of the rotatable portion.

[0063] In the axial pressure wheel assembly, by symmetrically arranging the first pressure wheel element and the second pressure wheel element at both ends of the connecting rod, the connecting rod is kept rotating around its central axis, thereby adaptively adjusting the displacement of the rotatable part.

[0064] As shown in FIG. 5C , in the axial pressure wheel assembly, each of the first pressure wheel element 228 and the second pressure wheel element 229 includes at least two axial pressure wheels 230 stacked in sequence along the wheel axis direction.

[0065] For example, the surface of any one of the first piezo wheel component 228 and the second piezo wheel component 229 may be a cylindrical surface.

[0066] It should be noted that, in the axial pressure wheel group, the central axes of the first pressure wheel element 228 and the second pressure wheel element 229 coincide with the central axis of the wheel shaft 226, and the first pressure wheel element 228 and the second pressure wheel element 229 rotate on the wheel shaft 226. The minimum distance a between at least a portion of the outer peripheral surface of any axial pressure wheel 230 and the end face of any rotating track along the direction of the rotation axis remains unchanged.

[0067] It is understood that when the rotatable portion is displaced along the rotation axis during rotation, the rotating track contacts the axial pressure wheel and generates thrust, causing the axial pressure wheel to rotate about the wheel axis, thereby causing the connecting rod to rotate about its central axis. At this time, the minimum distance between the outer circumference of each pressure wheel at both ends of the connecting rod and the rotating track is the same.

[0068] In some exemplary embodiments of the present disclosure, please refer to Figure 5A, the fixing seat 221 has two screw holes symmetrically preset on both sides of the center of the rotatable part 2, and the fixing seat 221 is fixedly connected to the frame 110 by mounting bolts 2210 installed in the two screw holes.

[0069] Figure 6A is a schematic diagram of the structure of an eccentric pressure wheel assembly of a CT device according to some exemplary embodiments of the present disclosure. Figure 6B is a schematic diagram of the partial structure of a pressure wheel element in an eccentric pressure wheel assembly of a CT device according to some exemplary embodiments of the present disclosure.

[0070] As shown in Figures 6A and 6B, the second pressure wheel assembly 5 (for example, the eccentric pressure wheel assembly) includes: a fixed base 221, a connecting rod 222, a first bearing 223, a rotating shaft 224, a wheel seat 225, a wheel axle 226, a second bearing 227, a first pressure wheel element 228' and a second pressure wheel element 229'.

[0071] The fixing seat 221 is fixedly connected to the frame 110, the outer ring of the first bearing 223 is fixed on the fixing seat 221, the rotating shaft 224 is fixed to the inner ring of the first bearing 223, and the connecting rod 222 is set on the rotating shaft 224. The inner ring of the first bearing 223 cooperates with the rotating shaft 224 to enable the connecting rod 222 to rotate.

[0072] The wheel seat 225 is set on both ends of the connecting rod 222. At each end of the connecting rod 222, the wheel axle 226 is fixed on the wheel seat 225, the first pressure wheel element 228' is set on the wheel axle 226 through the second bearing 227, and the second pressure wheel element 229' is set on the wheel axle 226 through the second bearing 227.

[0073] 6A , the first pressure wheel element 228 ′ and the second pressure wheel element 229 ′ are symmetrically arranged on the connecting rod about the center of the rotatable portion.

[0074] 6B , in the eccentric pressure wheel assembly, each of the first pressure wheel element 228 ′ and the second pressure wheel element 229 ′ includes at least two eccentric pressure wheels 230 ′ stacked in sequence along the wheel axis direction.

[0075] That is, in the eccentric pressure wheel assembly, since the wheel shaft 226 is an eccentric shaft, the central axes of the first pressure wheel element 228' and the second pressure wheel element 229' do not coincide with the central axis of the wheel shaft 226, and the eccentric pressure wheels 230' on the first pressure wheel element 228' and the second pressure wheel element 229' rotate eccentrically on the wheel shaft 226.

[0076] It is understandable that when the rotatable part is displaced along the rotation axis during rotation, the rotating track will contact the eccentric pressure wheel and generate thrust, which will cause the eccentric pressure wheel to begin to rotate, thereby causing the connecting rod to rotate around the central axis of the connecting rod in a plane parallel to the rotation axis. However, since the wheel shaft is an eccentric shaft, the eccentric pressure wheel does not rotate around the wheel shaft, but instead moves eccentrically with the action of the thrust. Therefore, the minimum distance b along the rotation axis between at least a portion of the outer peripheral surface of any eccentric pressure wheel and the end face of any rotating track is variable.

[0077] In the above embodiment of the CT device disclosed herein, by respectively arranging a group of axial pressure wheel groups and a group of eccentric pressure wheel groups on the end faces of the rotatable part, when the rotatable part generates displacement along the direction of the rotation axis during rotation, the rotating track will come into contact with the pressure wheels in the pressure wheel groups on both sides, causing the eccentric pressure wheel group and the axial pressure wheel group to rotate around the connecting rod. At this time, the minimum distance a along the direction of the rotation axis between at least a portion of the outer circumference of the axial pressure wheel and the end face of any rotating track and the minimum distance b along the direction of the rotation axis between at least a portion of the outer circumference of any eccentric pressure wheel and the end face of any rotating track jointly adjust and limit the movement displacement of the rotatable part along the direction of the rotation axis. It can effectively ensure that both sides of the axial end face of the rotatable part can contact the pressure wheel group at multiple points, ensure the unique position of the rotatable part, make the CT device imaging accurate, improve the life of the device, and also help reduce the operating noise of the device.

[0078] In other embodiments, the rotating shaft in the eccentric pressure wheel assembly is configured as an eccentric shaft, and the specific implementation is as follows.

[0079] The eccentric pressure wheel assembly also includes: a rotating shaft 224 is set as an eccentric rotating shaft, the rotating shaft 224 is fixed to the inner ring of the first bearing 223, the inner ring of the first bearing 223 cooperates with the eccentric rotating shaft to make the connecting rod rotate eccentrically, the wheel seat 225 is set on both ends of the connecting rod 222, at each end of the connecting rod 222, the wheel axle 226 is fixed on the wheel seat 225, the first pressure wheel element 228' is set on the wheel axle 226 through the second bearing 227, and the second pressure wheel element 229' is set on the wheel axle 226 through the second bearing 227.

[0080] It should be noted that, at this time, each of the first pressure wheel element 228 ′ and the second pressure wheel element 229 ′ includes at least two axial pressure wheels 230 stacked in sequence along the wheel axis direction.

[0081] It can be understood that when the rotating shaft in the eccentric pressure wheel group is set as an eccentric shaft, when the rotatable part produces a displacement along the direction of the rotation axis during rotation, the rotating track will contact the axial pressure wheel and generate thrust, which will cause the connecting rod to rotate eccentrically on a plane parallel to the rotation axis. At this time, the minimum distance b' along the direction of the rotation axis between at least a part of the outer peripheral surface of any axial pressure wheel and the end face of any rotating track is variable.

[0082] According to the embodiment of the present disclosure, the rotating shaft in the eccentric pressure wheel group is set as an eccentric shaft, and the distance from the axial pressure wheel group can be adjusted, thereby effectively limiting the movement displacement of the rotatable part along the direction of the rotation axis.

[0083] In other embodiments, another specific implementation of the eccentric pressure wheel assembly is as follows.

[0084] FIG7 is a partial structural diagram of the connection between a fixing seat and a gantry in another eccentric pressure wheel assembly of a CT device according to some exemplary embodiments of the present disclosure.

[0085] As shown in Figures 5A and 7, the outer ring of the first bearing 223 is fixed on the fixed seat 221, the rotating shaft 224 is fixed to the inner ring of the first bearing 223, and the connecting rod 222 is set on the rotating shaft 224. The inner ring of the first bearing 223 cooperates with the rotating shaft 224 to enable the connecting rod 222 to rotate. The fixed seat 221 is fixedly connected to the frame 110 in such a way that the fixed seat 221 is symmetrically provided with long holes 2220 along the direction of the rotation axis on both sides of the center of the rotatable part. By installing the bolts 2210, the fixed seat 221 can move along the long holes 2220.

[0086] It should be noted that, at this time, each pressure wheel element includes at least two axial pressure wheels stacked in sequence along the wheel axis direction.

[0087] It can be understood that when the rotatable part generates displacement along the direction of the rotation axis during rotation, the rotating track will contact the axial pressure wheel and generate thrust, and the eccentric pressure wheel group will move along the direction of the rotation axis in the preset mounting long hole along with the fixed seat. At this time, the distance between the eccentric pressure wheel group and the axial pressure wheel group can be adjusted, thereby effectively limiting the movement displacement of the rotatable part along the direction of the rotation axis.

[0088] According to the embodiments of the present disclosure, during operation of the CT device, a set of adaptive wheels is provided on each side of the imaging system, ensuring that both sides of the axial end face of the imaging system can make multi-point contact with the pressure wheel assembly, thus ensuring the unique position of the imaging system. This improves imaging accuracy, extends the life of the CT device, and also helps reduce operating noise.

[0089] FIG8 is a schematic structural diagram of a magnetic device of a CT apparatus according to another exemplary embodiment of the present disclosure.

[0090] As shown in FIG8 , the CT device 100 further includes a magnetic device 6 , which is disposed on the gantry 110 and configured to provide a magnetic attraction force to the rotatable part 2 when the rotatable part 2 rotates, thereby applying an adsorption force to the rotatable part 2 toward the gantry 110 .

[0091] Exemplarily, the magnetic device 6 includes a plurality of permanent magnets or electromagnets, which are arranged on the frame in a manner spaced apart from each other along the rotation direction of the rotatable part 2 .

[0092] For example, the plurality of permanent magnets or electromagnets are arranged on the frame at uniform intervals along the rotation direction of the rotatable portion. For example, the plurality of permanent magnets are arranged on the frame along the outer circumference of the rotatable portion, and can be arranged in the lower area of ​​the frame or in other areas of the frame.

[0093] As shown in Figures 3 and 4, the rotatable portion 2 includes a rotatable body 22 and two rotatable rails. The scanning device 31 is disposed on the rotatable body 22. In some embodiments, the rotatable rails comprise a magnetic material. In some optional embodiments, a magnetic portion composed of a magnetic material is mounted on the outer circumference of the rotatable rails. This magnetic portion can attract the magnetic device, thereby applying an attractive force to the rotatable portion 2 toward the frame 110.

[0094] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0095] Although embodiments of the present disclosure have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and purpose of the present disclosure, and that the scope of the present disclosure is defined by the claims and their equivalents. It will be understood by those skilled in the art that the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in the present disclosure. In particular, the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in various ways, without departing from the spirit and teachings of the present disclosure. All of these combinations and / or combinations fall within the scope of the present disclosure.

Claims

1. A CT device, comprising: a gantry; a support device disposed on the gantry, the support device including a plurality of rotating wheels, wherein at least one rotating wheel of the support device serves as a driving wheel; a rotatable part that can rotate around a rotation axis under the drive of the driving wheel, and during the rotation of the rotatable part, the rotatable part is jointly supported by the plurality of support devices; a scanning device disposed on the rotatable part, the scanning device being configured to scan an item to be inspected; an axial limiting mechanism, including a first pressing wheel group and a second pressing wheel group, along the direction of the rotation axis, the first pressing wheel group and the second pressing wheel group are respectively disposed on two end faces of the rotatable part; wherein each of the first pressing wheel group and the second pressing wheel group includes n pressing wheels, n is an integer greater than 3, and at least a part of the outer peripheral surface of any one of the pressing wheels is in contact with the end face of the rotatable part to limit the movement of the rotatable part along the rotation axis direction.

2. The CT device according to claim 1, wherein, One of the first pressing wheel group and the second pressing wheel group includes an eccentric pressing wheel group, and the other of the first pressing wheel group and the second pressing wheel group includes an axial pressing wheel group; or, both the first pressing wheel group and the second pressing wheel group are axial pressing wheel groups; or, both the first pressing wheel group and the second pressing wheel group are eccentric pressing wheel groups.

3. The CT device according to claim 2, wherein, In a direction parallel to the rotation axis, the rotatable part sequentially includes a first rotating track, a rotatable part body, and a second rotating track. In a direction parallel to the rotation axis, the first pressing wheel group is disposed on a side of the first rotating track away from the rotatable part body, and the second pressing wheel group is disposed on a side of the second rotating track away from the rotatable part body.

4. The CT device according to claim 3, wherein, Both the axial pressing wheel group and the eccentric pressing wheel group include: a fixed seat, a connecting rod, a first bearing, a rotating shaft, a wheel seat, a wheel shaft, a second bearing, a first pressing wheel element, and a second pressing wheel element. The fixed seat is fixedly connected to the gantry, the outer ring of the first bearing is fixed on the fixed seat, the rotating shaft is fixedly connected to the inner ring of the first bearing, and the connecting rod is disposed on the rotating shaft. The wheel seats are disposed at both ends of the connecting rod. At each end of the connecting rod, the wheel shaft is fixed on the wheel seat, the first pressing wheel element is disposed on the wheel shaft through the second bearing, and the second pressing wheel element is disposed on the wheel shaft through the second bearing.

5. The CT device according to claim 4, wherein, The first pressing wheel element and the second pressing wheel element are symmetrically arranged about the center of the rotatable part on the connecting rod.

6. The CT device according to claim 4, wherein, The fixed seat is symmetrically provided with two preset screw holes on both sides of the center of the rotatable part, and the fixed seat is fixedly connected to the gantry through mounting bolts installed in the two screw holes.

7. The CT device according to claim 4, wherein, In the axial pressing wheel group, each of the first pressing wheel element and the second pressing wheel element includes at least two axial pressing wheels stacked in sequence along the direction of the wheel shaft.

8. The CT device according to claim 7, wherein, In the axial pressure wheel set, the central axes of the first pressure wheel element and the second pressure wheel element both coincide with the central axis of the wheel shaft, the first pressure wheel element and the second pressure wheel element rotate on the wheel shaft, and the minimum distance a in the direction of the rotation axis between at least a part of the outer peripheral surface of any axial pressure wheel and the end surface of any rotation track remains unchanged.

9. The CT device according to claim 4, wherein, In the eccentric pressure wheel set, each of the first pressure wheel element and the second pressure wheel element includes at least two eccentric pressure wheels stacked in sequence along the direction of the wheel shaft.

10. The CT device according to claim 9, wherein, In the eccentric pressure wheel set, the wheel shaft is an eccentric shaft, the central axes of the first pressure wheel element and the second pressure wheel element do not coincide with the central axis of the wheel shaft, the first pressure wheel element and the second pressure wheel element rotate eccentrically on the wheel shaft, and the minimum distance b in the direction of the rotation axis between at least a part of the outer peripheral surface of any eccentric pressure wheel and the end surface of any rotation track is variable.

11. The CT device according to claim 10, wherein, The minimum distance a and the minimum distance b jointly adjust the movement of the rotatable part in the direction of the rotation axis.

12. The CT device according to claim 4, wherein, In the eccentric pressure wheel set, The rotating shaft is arranged as an eccentric rotating shaft, the rotating shaft is fixed to the inner ring of the first bearing, and the inner ring of the first bearing is matched with the eccentric rotating shaft so that the connecting rod rotates eccentrically. Each of the first pressure wheel element and the second pressure wheel element includes at least two axial pressure wheels stacked in sequence along the direction of the wheel shaft.

13. The CT device according to claim 6, wherein, The eccentric pressure wheel set further includes: The fixed seat is provided with long holes symmetrically preset on both sides of the center of the rotatable part along the direction of the rotation axis, and the fixed seat can move along the long holes.

14. The CT device according to claim 4, wherein, The surface of any pressure wheel in the first pressure wheel element and the second pressure wheel element is a cylindrical surface.

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