CN214375220U - Balun assembly and cable assembly for magnetic resonance imaging system - Google Patents

Abstract

The utility model provides a balun subassembly and cable subassembly for magnetic resonance imaging system. The balun assembly includes: a balun assembly body having a central passage; the balun assembly shell is arranged on the outer side of the balun assembly body, holes corresponding to the central channel are formed in two ends of the balun assembly shell, and cables can pass through the central channel and the holes; wherein the balun assembly further includes a plurality of thermally conductive fins disposed about and extending from one end of the balun assembly body to the other end, the thermally conductive fins being in close proximity to and spaced apart from each other along the outer surface of the balun assembly body. According to the utility model discloses a balun subassembly can prevent local overheated phenomenon under the condition of hardly increasing its size.

Description

Balun assembly and cable assembly for magnetic resonance imaging system

Technical Field

The present invention relates to a nuclear magnetic resonance imaging system, and more particularly to a balun assembly for a nuclear magnetic resonance imaging system and a cable assembly including such a balun assembly.

Background

The nuclear magnetic resonance imaging system is widely used due to the characteristics of high image definition, capability of multi-azimuth thin-layer scanning, high diagnosis rate on difficult and complicated diseases, no pain and no damage to human bodies and the like. When a specific part of the body of a patient needs to be scanned and imaged, a special coil unit needs to be arranged at the part of the patient needing to be scanned and imaged, and the coil unit is connected with a host of a magnetic resonance imaging system through a cable assembly to transmit an electric signal.

During the operation of the nuclear magnetic resonance imaging system, strong alternating magnetic field and alternating electric field are generated in the system due to the emitted radio frequency, so that strong eddy currents are induced on the cable, and the eddy currents can seriously influence the imaging quality of the nuclear magnetic resonance imaging system. For this reason, it is necessary to provide a balun assembly (also referred to as a "balun") on the cable through which the cable passes, forming a resonant tank, in order to prevent or reduce eddy currents generated in the cable.

With the use of the new generation of magnetic resonance imaging system, more and more coil channels are arranged in the coil unit, resulting in more and more thermal power of the coil unit. This in turn can lead to heating of the balun component, and in particular local overheating at and around the location where the capacitance of the balun component is provided. When the balun component is in contact with a human body, the locally overheated part can burn the human body, and serious potential safety hazards exist.

In order to prevent local overheating of the balun component, one existing solution is to increase the housing of the balun component to increase the heat dissipation area. This approach, however, significantly increases the size of the balun assembly, resulting in reduced portability and usability of the balun assembly.

Therefore, there is a need for an improvement of the prior art balun assembly for magnetic resonance imaging systems.

SUMMERY OF THE UTILITY MODEL

An object of the present invention is to overcome at least one of the above-mentioned drawbacks in the prior art, and to provide a balun component for a nuclear magnetic resonance imaging system and a cable component including such a balun component, which can prevent local overheating of the balun component without increasing its size.

According to an aspect of the present invention, there is provided a balun assembly for a nuclear magnetic resonance imaging system, comprising:

a balun assembly body having a central passage;

the balun assembly is characterized by further comprising a plurality of heat conducting fins arranged around the outer surface of the balun assembly body, wherein the plurality of heat conducting fins are attached to the outer surface of the balun assembly body in an abutting mode and are mutually and electrically insulated.

Preferably, the plurality of heat conduction fins extend from one end to the other end of the balun assembly body.

Preferably, the heat conducting sheet is made of nonmagnetic metal or nonmagnetic alloy.

Preferably, the heat-conducting fins are spaced apart from each other along a circumferential direction of the balun assembly body.

Preferably, the surface of the thermally conductive sheet is subjected to an insulating treatment.

Preferably, the balun assembly further comprises a balun assembly housing disposed outside the balun assembly body, a hole corresponding to the central channel is formed at two ends of the balun assembly housing, and the central channel and the hole are used for passing through a cable.

Preferably, the balun assembly further includes a first support ring for supporting a first end of the plurality of heat-conducting fins and a second support ring for supporting a second end of the plurality of heat-conducting fins.

Preferably, the first support ring and the second support ring each include a support end plate having a central hole, a plurality of arc-shaped grooves spaced apart by a spacing rib are formed on an end surface of the support end plate in a circumferential direction, and the heat-conductive fins are also arc-shaped.

Preferably, the balun assembly further includes a third support ring disposed around the plurality of heat-conducting fins and between the first support ring and the second support ring, the third support ring having a cylindrical shape and having partition ribs formed on an inner wall thereof in correspondence with the partition ribs.

Preferably, the plurality of heat-conducting fins are fixed on the outer surface of the balun assembly body by an adhesive, an insulating fastening device or an insulating encapsulating layer.

According to another aspect of the present invention, there is provided a cable assembly for a mri system, the cable assembly is used for connecting a coil unit of the mri system with a host of the mri system, and includes a cable and a balun assembly disposed on the cable, wherein the balun assembly is the balun assembly as described above.

According to the utility model discloses a balun subassembly for nuclear magnetic resonance imaging system, because the conducting strip extends to a plurality of conducting strips of the other end from the one end of balun subassembly body, the local too high heat of balun subassembly body can be through the transmission of conducting strip and vertically spread evenly along whole balun subassembly body, and then prevents local overheat phenomenon, avoids human and balun subassembly contact and is burnt. Simultaneously, because the conducting strip does not occupy extra space hardly, according to the utility model discloses a balun subassembly's size can not increase hardly.

Drawings

Fig. 1 schematically shows a cable assembly equipped with a balun assembly for a magnetic resonance imaging system according to a first embodiment of the present invention;

FIG. 2 schematically illustrates the balun assembly of FIG. 1 with a cable passing therethrough, with one of the housing halves removed;

FIG. 3 is a cross-sectional schematic view taken along line A-A in FIG. 2;

fig. 4 is an exploded perspective view of the balun assembly for a magnetic resonance imaging system according to a preferred embodiment of the present invention in fig. 1;

fig. 5 schematically shows a plurality of heat conductive fins mounted to the first support ring;

FIG. 6 is an end view of the first support ring of FIG. 5 with a plurality of thermally conductive fins mounted thereon;

FIG. 7 is a cross-sectional schematic view taken along line B-B in FIG. 6;

FIG. 8 is an enlarged schematic view of circled portion C of FIG. 7;

fig. 9 schematically shows the balun assembly body installed into the assembly shown in fig. 5;

FIG. 10 schematically illustrates the second and third support rings being mounted to the assembly shown in FIG. 9;

fig. 11 schematically illustrates a balun assembly for a magnetic resonance imaging system according to a preferred embodiment of the invention, wherein one half shell has not yet been mounted;

figure 12 schematically shows a balun assembly for a magnetic resonance imaging system according to a second embodiment of the invention;

FIG. 13 is a side view of the balun assembly shown in FIG. 12;

FIG. 14 is an end view of the balun assembly shown in FIG. 12;

figure 15 schematically shows a balun assembly for a magnetic resonance imaging system according to a third embodiment of the invention;

FIG. 16 is a side view of the balun assembly shown in FIG. 15;

FIG. 17 is a cross-sectional schematic view taken along line 17-17 of FIG. 16;

FIG. 18 is a cross-sectional view taken along line 18-18 of FIG. 16;

figure 19 schematically shows a balun assembly for a nuclear magnetic resonance imaging system according to a fourth embodiment of the invention;

FIG. 20 is a side view of the balun assembly shown in FIG. 19;

FIG. 21 is a cross-sectional view taken along line 21-21 of FIG. 20; and

fig. 22 is a cross-sectional view taken along line 20-20 in fig. 20.

Detailed Description

Preferred embodiments of the present invention are described in detail below with reference to examples. It will be understood by those skilled in the art that these exemplary embodiments are not meant to limit the invention in any way.

Fig. 1 schematically shows a cable assembly equipped with a balun assembly for an mri system according to a first embodiment of the present invention, fig. 2 schematically shows the balun assembly of fig. 1 through which a cable is passed, wherein one half-shell is detached, fig. 3 is a schematic cross-sectional view taken along line a-a in fig. 2, and fig. 4 is an exploded perspective view of the balun assembly for an mri system according to a preferred embodiment of the present invention in fig. 1. As shown in fig. 1 to 3, the balun assembly 1 for a magnetic resonance imaging system according to the present invention includes an elongated balun assembly body 3 and a balun assembly housing 5 disposed outside the balun assembly body 3. The balun component body 3 is provided with an elongated central channel 7, the balun component shell 5 is provided with holes 8 corresponding to the central channel 7 at two ends, and a cable 9 for connecting the coil unit with the nuclear magnetic resonance imaging system host passes through the elongated central channel 7 of the balun component body 3 and the holes 8 at two ends of the balun component shell 5, so that the balun component is sleeved on the cable 9 to form a cable component 10. The balun component, which is sheathed on the cable 9, forms a resonant circuit in order to suppress or reduce eddy currents generated in the cable. Since the present invention does not relate to the improvement of the balun assembly body 3, the detailed description of the balun assembly body 3 is omitted.

As shown in fig. 2 to 4, the balun assembly 1 for a magnetic resonance imaging system according to the present invention further includes a plurality of elongated heat conducting fins 11 disposed around the outer surface of the balun assembly body 3 and extending from one end to the other end of the balun assembly body 3, the plurality of elongated heat conducting fins 11 being closely attached to the outer surface of the balun assembly body 3 and spaced apart from each other along the circumferential direction of the balun assembly body to achieve electrical insulation. The fact that the elongated heat-conductive fins 11 are closely attached to the outer surface of the balun assembly body 3 means that the elongated heat-conductive fins 11 are in close contact with the balun assembly body 3 so that heat can be transferred from the balun assembly body 3 to the elongated heat-conductive fins 11. The plurality of elongate heat-conducting fins 11 are spaced apart from each other along the outer surface of the balun assembly body in order to minimize eddy currents generated in the elongate heat-conducting fins 11 while avoiding sparking between adjacent elongate heat-conducting fins. The elongated heat conductive sheet 11 is made of a material having no magnetism and good heat conductive properties, such as a non-magnetic metal or a non-magnetic alloy. Further, it is also possible to apply an insulating treatment such as an insulating varnish, an insulating layer plating, or an oxidation treatment to the surface of the elongate heat-conductive sheet 11 to make the elongate heat-conductive sheet 11 nonconductive to prevent eddy currents generated in the elongate heat-conductive sheet 11 from flowing toward the balun assembly body. Because the slender heat-conducting fins extend from one end of the balun assembly body 3 to the plurality of slender heat-conducting fins 11 at the other end, heat generated by the balun assembly body 3, especially local overhigh heat, can be uniformly diffused along the whole balun assembly body 3 longitudinally through the transmission of the slender heat-conducting fins 11, so that the heat generated by the balun assembly body 3 can be more quickly diffused into the surrounding environment, the local overheating phenomenon is further prevented, and the human body is prevented from being burnt due to the contact with the balun assembly. At the same time, since the elongated heat conducting fins hardly occupy additional space, the balun assembly according to the present invention hardly increases in size. Although in the preferred embodiment the elongate heat conducting fins 11 extend on the outer surface of the balun assembly body 3 along a direction substantially parallel to the longitudinal central axis of the balun assembly body 3, it will be appreciated that it is also possible for the elongate heat conducting fins 11 to extend curved, e.g. helically, against the outer surface of the balun assembly body 3.

In order to make the plurality of elongated heat-conducting fins 11 tightly contact the outer surface of the balun assembly body 3 and be arranged along the outer surface of the balun assembly body in a spaced manner, the balun assembly 1 for a magnetic resonance imaging system according to the present invention further comprises a first support ring 13 for supporting a first end of the plurality of elongated heat-conducting fins 11 and a second support ring 15 for supporting a second end of the plurality of elongated heat-conducting fins 11. The first support ring 13 and the second support ring 15 have substantially the same structure, and the structure of the first support ring 13 will be described below with reference to fig. 5 to 8. The first support ring 13 comprises a support end plate 19 having a central aperture 17. A central bore 17 through which the cable passes. A plurality of spaced arcuate grooves 21 are formed in the end face of the support end plate 19 in the circumferential direction, with adjacent arcuate grooves 21 being separated by spacing ribs 23. The adjacent arc-shaped grooves 21 are sized so that the corresponding elongate heat-conducting fins 11 can be inserted therein and held in place while the inner diameter of the substantially cylindrical space defined by the plurality of elongate heat-conducting fins 11 inserted in the arc-shaped grooves 21 is made substantially the same as the outer diameter of the balun assembly body 3. As a result, the plurality of elongated heat conductive fins 11 can be closely attached to the outer surface of the balun assembly body 3 when the balun assembly body 3 is mounted in place. In order to reliably hold the plurality of elongated heat-conducting fins 11 on the outer surface of the balun assembly body 3 after the balun assembly body 3 is mounted in place, the outer side wall defining the arc-shaped groove 21 may extend from the support end plate 19 in a direction toward the position of the elongated heat-conducting fins to form a protective wall 25 that prevents the elongated heat-conducting fins from falling out of the arc-shaped groove 21. The partition ribs 23 may extend along with the protective wall 25.

In order to further securely hold the plurality of elongate heat-conducting fins 11 in place on the balun assembly body 3, a third support ring 27 may be provided around the plurality of elongate heat-conducting fins 11 between the first support ring 13 and the second support ring 15. The third support ring 27 is cylindrical and includes on its inner wall spacing ribs 29 corresponding to the spacing ribs 23. The third support ring 27 may be formed with respective flanges 27a at both side edges to interact with annular ribs 5a on the inner wall of the balun assembly housing 5 to prevent longitudinal movement of the third support ring 27 on the plurality of elongate heat-conducting fins 11.

The assembly process of the balun assembly 1 for a magnetic resonance imaging system according to the preferred embodiment of the present invention will be described in detail with reference to fig. 5 to 11.

First, as shown in fig. 5 to 8, the first ends of the plurality of elongated heat conductive fins 11 are inserted into the respective arc-shaped grooves 21 on the first support ring 13, and the adjacent arc-shaped grooves 21 are separated by the partition ribs 23. Since the elongated heat-conducting fin 11 needs to be inserted into the arc-shaped groove 21 and is to be closely attached to the outer surface of the balun assembly body 3, the elongated heat-conducting fin 11 should also be arc-shaped.

Next, as shown in fig. 9, the balun assembly body 3 is inserted into the assembly as shown in fig. 5, the balun assembly body 3 substantially abutting against the support end plate 19 of the first support ring 13. Then, as shown in fig. 10, the third support ring 27 is fitted over the plurality of elongate heat-conducting fins 11 with the partition ribs 29 on the inner wall of the third support ring 27 being located between the adjacent elongate heat-conducting fins 11. Next, the second ends of the plurality of elongated heat-conducting fins 11 are inserted into the corresponding arc-shaped grooves on the second support ring 15, respectively.

The balun assembly housing 5 may comprise two housing halves that can be snapped together. The balun assembly body 3 with the plurality of heat conductive fins 11 as shown in fig. 10 is set in one half shell of the balun assembly housing 5 as shown in fig. 11. A plurality of semicircular ribs 5a are formed at intervals on the inner wall of each half shell, and when the two half shells are fastened together, the semicircular ribs 5a can keep the balun assembly body 3 provided with the plurality of heat-conducting fins 11 substantially centrally in the inner space of the balun assembly housing 5, and some of the semicircular ribs 5a also play a role of limiting the displacement of the third support ring 27 and the second support ring 25 at the same time. For this purpose, the outer edge of the second support ring 25 may also be formed with an annular flange 15a which can interact with the semicircular ribs 5a if necessary. Finally, the other half-shell is snapped onto the assembly as shown in fig. 11 and screws are screwed into the screw holes 31 in the half-shells, locking the two half-shells together, thereby completing the assembly of the balun assembly. It should be understood that the balun assembly housing 5 may be omitted.

Fig. 12 schematically shows a balun assembly for a magnetic resonance imaging system according to a second embodiment of the invention, fig. 13 is a side view of the balun assembly shown in fig. 12, and fig. 14 is an end view of the balun assembly shown in fig. 12. In the balun assembly 1 according to the second embodiment of the present invention shown in fig. 12 to 14, the plurality of elongated heat conductive sheets 11 are directly stuck to the outer surface of the balun assembly body 3 by an adhesive such as glue or a foaming agent, and thus the first support ring 13, the second support ring 15, the third support ring 27, and the balun assembly housing 5 used in the first embodiment can be omitted.

Fig. 15 schematically shows a balun assembly for a nuclear magnetic resonance imaging system according to a third embodiment of the invention, fig. 16 is a side view of the balun assembly shown in fig. 15, fig. 17 is a schematic cross-sectional view taken along line 17-17 in fig. 16, and fig. 18 is a schematic cross-sectional view taken along line 18-18 in fig. 16. In the balun assembly 1 according to the third embodiment of the present invention shown in fig. 15 to 18, the plurality of elongated heat-conducting fins 11 are fixed to the outer surface of the balun assembly body 3 by the insulating fastening means 33 of heat shrinkable tube or tape or the like, and thus the first support ring 13, the second support ring 15, the third support ring 27 and the like used in the first embodiment can be omitted. Furthermore, the balun assembly housing 5 may also be omitted, since the fastening means 33 also at least partially encases the plurality of elongated heat conducting fins 11.

Fig. 19 schematically shows a balun assembly for a nuclear magnetic resonance imaging system according to a fourth embodiment of the invention, fig. 20 is a side view of the balun assembly shown in fig. 19, fig. 21 is a schematic cross-sectional view taken along line 21-21 in fig. 20, and fig. 22 is a schematic cross-sectional view taken along line 22-20 in fig. 20. In the balun assembly 1 according to the fourth embodiment of the present invention shown in fig. 19 to 22, the insulating envelope layer 35 is formed by an integral molding process such as injection molding or the like so as to integrally envelope the plurality of elongated heat-conducting fins 11 with the balun assembly body 3, thereby fixing the plurality of elongated heat-conducting fins 11 on the outer surface of the balun assembly body 3. According to this embodiment, the first support ring 13, the second support ring 15, the third support ring 27, the balun assembly housing 5, and the like used in the first embodiment may be omitted.

It can be seen from the above embodiments that the balun component according to the present invention can be provided with a balun component housing as required, and can also omit the balun component housing. In case the balun assembly housing is omitted, the weight of the balun assembly may be further reduced while also facilitating the dissipation of heat. In the above exemplary embodiment, the balun assembly body is shown as a cylinder, it being understood that the balun assembly body may also be of other suitable shapes such as a triangular prism or a rectangular parallelepiped. Further, although a plurality of heat conductive fins are shown extending from one end to the other end of the balun assembly body in the above exemplary embodiment, it is to be understood that all or part of the heat conductive fins may extend along only a part of the outer surface of the balun assembly body. The heat-conductive fins extending along a part of the outer surface of the balun assembly body may be either aligned with each other or offset from each other in the longitudinal direction of the balun assembly body.

While the invention has been described in detail in connection with the preferred embodiments thereof, it is to be understood that such detail is solely for that purpose and that no limitation of the invention is thereby intended. The scope of the present invention is defined by the claims.

Claims (11)

1. A balun assembly (1) for a magnetic resonance imaging system, comprising:

a balun assembly body (3), the balun assembly body (3) having a central passage (7);

the balun assembly (1) is characterized by further comprising a plurality of heat conducting fins (11) arranged around the outer surface of the balun assembly body (3), wherein the plurality of heat conducting fins (11) are attached to the outer surface of the balun assembly body (3) and are mutually and electrically insulated.

2. A balun assembly (1) for a magnetic resonance imaging system according to claim 1, wherein the plurality of heat conducting fins (11) extend from one end to the other end of the balun assembly body (3).

3. A balun assembly (1) for a magnetic resonance imaging system according to claim 1, wherein the heat conducting sheet (11) is made of a non-magnetic metal or a non-magnetic alloy.

4. A balun assembly (1) for a magnetic resonance imaging system according to claim 1, wherein the heat conducting fins (11) are mutually spaced along a circumferential direction of the balun assembly body.

5. A balun assembly (1) for a magnetic resonance imaging system according to claim 1, wherein the surface of the thermally conductive sheet (11) is insulated.

6. A balun assembly (1) for a magnetic resonance imaging system according to claim 1, wherein the balun assembly (1) further comprises a balun assembly housing (5) arranged outside the balun assembly body (3), the balun assembly housing (5) being formed with a hole (8) at both ends corresponding to the central channel (7), the central channel (7) and the hole (8) being for passing of cables.

7. A balun assembly (1) for a magnetic resonance imaging system according to claim 1, wherein the balun assembly (1) further comprises a first support ring (13) for supporting a first end of the plurality of heat conducting fins (11) and a second support ring (15) for supporting a second end of the plurality of heat conducting fins (11).

8. A balun assembly (1) for a magnetic resonance imaging system according to claim 7, wherein the first support ring (13) and the second support ring (15) each comprise a support end plate (19) having a central hole (17), a plurality of arc-shaped grooves (21) spaced apart by spacing ribs (23) are formed on an end face of the support end plate (19) in a circumferential direction, and the heat-conducting fins (11) are also arc-shaped.

9. A balun assembly (1) for a magnetic resonance imaging system according to claim 8, further comprising a third support ring (27) arranged around the plurality of heat conducting fins (11) and between the first support ring (13) and the second support ring (15), the third support ring (27) being cylindrical and having on an inner wall separation ribs (29) corresponding to the separation ribs (23).

10. A balun assembly (1) for a magnetic resonance imaging system according to claim 1, wherein the plurality of heat conducting fins (11) are fixed on the outer surface of the balun assembly body (3) by means of an adhesive, an insulating fastening means (33) or an insulating encapsulating layer (35).

11. A cable assembly for a magnetic resonance imaging system, the cable assembly being adapted to connect a coil unit of the magnetic resonance imaging system to a main unit of the magnetic resonance imaging system and comprising a cable and a balun assembly fitted around the cable, wherein the balun assembly is a balun assembly according to any one of claims 1 to 10.

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