CN109674472A - Pole plate and magnet for magnetic resonant imaging with the pole plate - Google Patents
Pole plate and magnet for magnetic resonant imaging with the pole plate Download PDFInfo
- Publication number
- CN109674472A CN109674472A CN201811641077.1A CN201811641077A CN109674472A CN 109674472 A CN109674472 A CN 109674472A CN 201811641077 A CN201811641077 A CN 201811641077A CN 109674472 A CN109674472 A CN 109674472A
- Authority
- CN
- China
- Prior art keywords
- ring
- magnetic material
- magnetic
- pole plate
- magnet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000003384 imaging method Methods 0.000 title claims abstract description 57
- 239000000696 magnetic material Substances 0.000 claims description 115
- 239000000463 material Substances 0.000 claims description 19
- 230000005389 magnetism Effects 0.000 claims description 6
- 229910000976 Electrical steel Inorganic materials 0.000 claims description 4
- 230000008901 benefit Effects 0.000 claims description 3
- 238000003475 lamination Methods 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 11
- 238000013461 design Methods 0.000 description 10
- 230000000694 effects Effects 0.000 description 5
- 238000002595 magnetic resonance imaging Methods 0.000 description 5
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000007373 indentation Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000005457 optimization Methods 0.000 description 2
- 208000019155 Radiation injury Diseases 0.000 description 1
- QJVKUMXDEUEQLH-UHFFFAOYSA-N [B].[Fe].[Nd] Chemical compound [B].[Fe].[Nd] QJVKUMXDEUEQLH-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000003745 diagnosis Methods 0.000 description 1
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 1
- 208000035475 disorder Diseases 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 229910001172 neodymium magnet Inorganic materials 0.000 description 1
- 230000005311 nuclear magnetism Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 210000004872 soft tissue Anatomy 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/05—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves
- A61B5/055—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F6/00—Superconducting magnets; Superconducting coils
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Physics & Mathematics (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Engineering & Computer Science (AREA)
- Heart & Thoracic Surgery (AREA)
- Molecular Biology (AREA)
- Pathology (AREA)
- Radiology & Medical Imaging (AREA)
- Biomedical Technology (AREA)
- High Energy & Nuclear Physics (AREA)
- Medical Informatics (AREA)
- Biophysics (AREA)
- Surgery (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Power Engineering (AREA)
- Magnetic Resonance Imaging Apparatus (AREA)
Abstract
The present invention provides a kind of pole plate and with the magnet for magnetic resonant imaging of the pole plate.The inner surface of the pole plate towards patient space are equipped with concentric compensation ring and stretch ring, and the compensation ring and stretch ring are bulge loop, wherein compensation ring is located inside stretch ring, the middle position in the inner surface；Stretch ring is located at the inner surface edge；And groove is additionally provided between compensation ring and stretch ring.Pole plate of the invention can not only expand imaging area range but also original uniformity of magnetic field can be kept not to be destroyed, so as to greatly reduce magnet weight under imaging range of condition on an equal basis.Pole plate of the invention can be applied to various magnet for magnetic resonant imaging.
Description
Technical field
The present invention relates to mr imaging technique fields, and in particular to a kind of pole plate and the magnetic with the pole plate is total
Shake image magnet.
Background technique
Magnetic resonance imaging (MRI) equipment is one of last century greatest invention, can almost be used for each position of human body
Scanning, does not have ionization radiation injury to human body, and soft tissue structure shows clearly, can be used for each site disorders diagnosis of whole body.
Magnet is a core component in MRI machine, for generating main field necessary to magnetic resonance imaging.Exist at present
There are three types of magnets used in clinical magnetic resonance imaging equipment: permanent-magnet, resistive magnet, superconducting magnet.
Wherein permanent-magnet operation and maintenance cost are low, and manufacturing cost is relatively low.Permanent-magnet is typically designed to out
Put formula structure, such as c-type, Double-pillar, four column types.Due to the limitation of magnetic material performance, permanent-magnet areas imaging is small, patient
Space is small compared with superconducting magnet, and usually in 400mm or so, and weight is compared with superconducting magnetic weight.
Its magnetic field of resistive magnet is generated by electromagnetic coil, and magnetic field disappears after power-off, needs that electromagnetic coil is kept to exist always
Energized state could work normally.Since coil resistance is not zero, power consumption is very big when work, and generates many heats and need
Cooling device remains operating status.Stability in use is poor, at present using less.
Superconducting magnet generates magnetic field by superconducting coil, and coil need to be maintained at low-temperature condition for a long time, therefore coil can be wrapped up
In cooled cryostat, its low-temperature condition is kept not to be destroyed using cold head.Superconducting magnet can design biggish patient space, usually
It is designed as tubular, imaging space is fully enclosed in inside magnet, and areas imaging is small, patient space's diameter 700mm or less.Superconducting line
Circle is generally cooled down using liquid helium, and operating cost is relatively high.
Specific application scenarios resistive magnet and superconducting magnet are also designed to open magnet, using often leading or superconducting line
Circle replaces permanent magnetism magnetic material, and overall structure is similar with permanent-magnet, including yoke, pole plate, grading ring, normal leads or superconducting line
Circle.This magnet has the characteristics that open, but the big deficiency that equally has that patient space is small, system consumes energy.
Specific application scenarios open magnet may be designed as several forms fusion shapes, such as be led or superconducting coil with normal
Instead of part magnetic material, structure type is similar with permanent-magnet, including yoke, pole plate, grading ring, permanent-magnet material, often leads
Or superconducting coil.The magnet have the characteristics that it is open, can use Coil Compensation magnet magnetic field deformation, expand imaging area model
It encloses, but equally has the small problem of patient space.
The technological means of conventional increase patient space, it will usually cause magnet pole spacing to increase, cause magnetic field levels
Direction is decayed faster, and for magnetic field error in 60PPM or so, this results in magnet imaging area range in magnetic resonance imaging requirement imaging area
It reduces, it is generally the case that can be improved by expanding the method for magnet diameter, but be bound to cause magnet weight and be significantly increased.
Pole plate is located at the two sides of patient space, and recently with imaging area distance, the influence to imaging area is very big, is commonly designed
For plate armature.The analysis found that the shape for changing pole plate is very big on imaging area influence, therefore it can use this spy
Point expands magnet imaging area range, makes up to imaging demand, thus the opposite weight for reducing magnet.
Summary of the invention
In consideration of it, the invention proposes a kind of pole plate and with the magnet for magnetic resonant imaging of the pole plate, it is intended to solve existing
The problem of.
The invention proposes a kind of pole plate, the inner surface of the pole plate towards patient space be equipped with concentric compensation ring and
Stretch ring, the compensation ring and stretch ring are bulge loop, wherein compensation ring is located inside stretch ring, in the inner surface
Between position；Stretch ring is located at the inner surface edge；And groove is additionally provided between compensation ring and stretch ring.
Further, above-mentioned compensation ring, stretch ring and groove are one.
Further, above-mentioned stretch ring is higher than compensation ring.
Further, above-mentioned compensation ring is anti-eddy current compensation ring.
Further, above-mentioned compensation ring is that silicon steel compensates ring or amorphous lamination compensates ring.
Another aspect of the present invention also provides a kind of magnet for magnetic resonant imaging, including above-mentioned pole plate.
Further, the magnet further includes yoke, magnetic material, grading ring, and the yoke inner surface is provided with a pair
Upper and lower symmetrical magnetic material is respectively equipped with pole plate on the opposite inner surface of the magnetic material, and the grading ring is fixed respectively
On the opposite inner surface of pole plate.
Further, above-mentioned magnetic material respectively includes the first magnetic material, the second magnetic material and third magnetic material,
Wherein the second magnetic material and third magnetic material arrange arc-shaped formation circumference, and the first magnetic material is laid in the circumference
Portion；The magnetic aligning of first magnetic material is that axially, the magnetic aligning of the second magnetic material and the axial direction are at α angle, third
The magnetic aligning of magnetic material and the axial direction are at β angle；The grading ring is being passed through along patient disengaging direction with symmetrical two
Logical notch, the height of the notch are less than or equal to grading ring height, and the thickness of the notch is equal to the thickness of grading ring, and described
The yoke of notch corresponding position, also corresponding vacancy forms notch to upper and lower magnetic material.
Further, above-mentioned magnetic material further includes the 4th magnetic material, between the first magnetic material and pole plate,
And around one circle of the inside of the second magnetic material and the formed circumference of third magnetic material arrangement, magnetic aligning and the first magnetic material
Expect identical.
Further, above-mentioned grading ring is additionally provided with the compensation shimming item of arcuation, fits in the two of the notch and notch
The grading ring inner wall of side.
Pole plate provided by the invention pulls out the magnetic field of magnet center by stretch ring, reduces the magnetic field of magnet center
Increase in imaging area simultaneously close to the magnetic field for stretching ring region, magnet imaging area range can be expanded；Pass through compensation ring compensation simultaneously
The low problem in imaging area central part magnetic field as caused by the stretching action of stretch ring.Groove between stretch ring and compensation ring
Two interannulars can be eliminated again due to synergistic effect bring magnetic field high point.Therefore pole plate of the invention can both expand imaging area
Range can keep original uniformity of magnetic field not to be destroyed again, so as to subtract significantly under imaging range of condition on an equal basis
Few magnet weight.Pole plate of the invention can be applied to various magnet for magnetic resonant imaging.
Detailed description of the invention
By reading the following detailed description of the preferred embodiment, various other advantages and benefits are common for this field
Technical staff will become clear.The drawings are only for the purpose of illustrating a preferred embodiment, and is not considered as to the present invention
Limitation.And throughout the drawings, the same reference numbers will be used to refer to the same parts.In the accompanying drawings:
Fig. 1 is existing magnet for magnetic resonant imaging structural schematic diagram one；
Fig. 2 is existing magnet for magnetic resonant imaging structural schematic diagram two；
Fig. 3 is existing magnet for magnetic resonant imaging structural schematic diagram three；
Fig. 4 is the electrode plate structure schematic diagram one of the embodiment of the present invention；
Fig. 5 is the electrode plate structure schematic diagram two of the embodiment of the present invention；
Fig. 6 is the magnet structure schematic diagram of the embodiment of the present invention；
Fig. 7 is the magnet pole schematic diagram of the embodiment of the present invention；
Fig. 8 A is one of the magnet magnetic aligning schematic diagram of the embodiment of the present invention；
Fig. 8 B is the two of the magnet magnetic aligning schematic diagram of the embodiment of the present invention.
Specific embodiment
Exemplary embodiments of the present disclosure are described in more detail below with reference to accompanying drawings.Although showing the disclosure in attached drawing
Exemplary embodiment, it being understood, however, that may be realized in various forms the disclosure without should be by embodiments set forth here
It is limited.On the contrary, these embodiments are provided to facilitate a more thoroughly understanding of the present invention, and can be by the scope of the present disclosure
It is fully disclosed to those skilled in the art.It should be noted that in the absence of conflict, embodiment in the present invention and
Feature in embodiment can be combined with each other.The present invention will be described in detail below with reference to the accompanying drawings and embodiments.
With reference to Fig. 1-3, for the permanent-magnet structure of several nuclear-magnetisms work imaging device common at present, wherein Fig. 3 is existing
Four cylindrical magnet structural schematic diagrams having.Magnet structure mainly includes yoke 1 ', magnetic material 2 ', pole plate 3 ', grading ring 4 ',
1 ' main function of yoke is that two parts magnetic material 2 ' up and down is connected, and is allowed to be formed into a loop, also functions to the work of two magnetic poles of support
With.Magnetic material 2 ' is for providing basic magnetic field used in magnetic resonance, the generally alloy materials such as neodymium iron boron, ferrite.Pole plate
3 ' main functions are support fixed magnetic material, and make the magnetic field of imaging region more evenly shape is generally one flat plate form.
Grading ring 4 ' is generally ring-type, and main function is to expand homogeneity range range, and magnetic field in magnet imaging area is made not to be gathered in center, and
It is to form the more uniform space in a magnetic field.
Magnetic material 2 ', pole plate 3 ', grading ring 4 ' arrangement symmetrical above and below.Uniformity of magnetic field reaches imaging between two pole plates 3 '
The area of space of demand is known as imaging area 8 ', generally spherical or elliposoidal.Space between two grading rings 4 ' is magnetic resonance
Patient's available space is scanned, can be referred to as patient space.But it is worth in actual use less apart from the farther away region of magnetic field center,
Image scanning have to allow imaging position include entirely in imaging area, therefore can cylindrical region package imaging area or ellipse
Region is known as available patient space 7 '.
According to existing design experiences, magnet, magnetic field 0.3T, patient space Φ are designed according to mode shown in Fig. 1-2
440mm, imaging area Φ 420mm* Φ 420mm* Φ 380mm(X*Y*Z) magnet weight is about 16 tons.As patient space increases to Φ
710mm, magnetic field remain unchanged, and magnet weight is up to 60 tons or more, bring big inconvenience for manufacture and use.
Referring to Figure 4 and 5, the electrode plate structure schematic diagram of the embodiment of the present invention is given, wherein Fig. 4 is the half-sectional solid of pole plate
Figure, Fig. 5 are pole plate sectional view.The inner surface of pole plate 3 towards patient space are equipped with concentric compensation ring 6 and stretch ring 5, compensation
Ring 6 and stretch ring 5 are bulge loop, are higher than polar board surface, wherein compensation ring 6 is located inside stretch ring 5, in pole plate inner surface
Middle position；Stretch ring 5 is located at pole plate inner surface edge, close to grading ring 4；And it is additionally provided between compensation ring 6 and stretch ring 5 recessed
Slot.
The effect of stretch ring 5 is that the magnetic field of magnet center is pulled out, and reduces the magnetic field of magnet center while increasing imaging area
The interior magnetic field close to stretching ring region, can expand magnet imaging area range.Compensation ring 6 is for compensating the stretching due to stretch ring 5
The low problem in imaging area central part magnetic field caused by effect.3 upper groove of pole plate is designed for eliminating two interannulars due to folded
Add effect bring magnetic field high point.This three parts collective effect can expand imaging area range can keep original magnetic field again
The uniformity is not by broken block, so as to reduce magnet weight under conditions of guaranteeing imaging area range.
Stretch ring 5 and compensation 6 size of ring and the position of 3 upper groove of pole plate, size need according to specific magnet and need into
Row optimization design determines, it is preferable that 5 height of stretch ring is greater than compensation ring 6.It is preferably compensated for ring 6 and needs to carry out anti-vortex generation
Design, using silicon steel or amorphous lamination, prevent due to compensation ring 6 generate extraneous turbulence, influence magnetic resonance system imaging
Quality.
The number of stretch ring 5, compensation ring 6 and groove between the two can be one or more, with specific reference to size
It is determined with process requirements.
Referring to Fig. 6-8, a magnet embodiment provided by the invention, wherein magnet includes yoke 1, magnetic material 2, pole plate
3, grading ring 4, in which: magnetic material 2, including the first magnetic material 2-1, the second magnetic material 2-3, third magnetic material 2-4,
Wherein the second magnetic material 2-3 and third magnetic material 2-4 arranges arc-shaped formation circumference, and the first magnetic material 2-1 is laid in
Among circumference；Wherein the first magnetic material 2-1 and magnetic aligning and axial direction；Second magnetic material 2-3, third magnetic material 2-4
Magnetic aligning made an angle alpha respectively with the axial direction, β.Specifically, upper and lower magnetic material 2 will form magnetic induction line closed loop, therefore upper magnetic
Property material, magnetic material the first magnetic material 2-1 magnetic aligning it is identical, such as Fig. 8 A, when upper magnetic material, magnetic material
The first magnetic material 2-1 magnetic aligning be axially upwards when, the second magnetic material 2-3 and third magnetism material of upper magnetic material
The magnetic aligning of material 2-4 is directional divergence axially upward, the second magnetic material 2-3 and third magnetic material of magnetic material
The magnetic aligning of 2-4 is that direction is gathered axially upward, is closed back so that the magnetic field of upper magnetic material 21, magnetic material 22 is formed
Road.As Fig. 8 B then goes up magnetic when the magnetic aligning of upper magnetic material, the first magnetic material 2-1 of magnetic material are axially downwardly
The magnetic aligning of the second magnetic material 2-3 and third magnetic material 2-4 of property material are to gather along the axially downward direction, under
The magnetic aligning of the second magnetic material 2-3 and third magnetic material 2-4 of magnetic material are directional divergence axially downward, thus on
The magnetic field formation closed circuit of magnetic material, magnetic material.
Since the first magnetic material 2-1 is laid in circumferential inner, the second magnetic material 2-3, third magnetic material 2-4 are around
The periphery arrangement of one magnetic material 2-1 is rounded, and magnetic aligning is any in space with the magnetic aligning of the first magnetic material 2-1 respectively
Towards at angle α, β, the efficiency that the angle α, β increase magnetic material 2 just be will increase, in the feelings using identical weight magnetic material
Higher field strength is obtained under condition, so as to mitigate the weight of magnet；The weight of yoke 1 can also be mitigated simultaneously.But magnetic field is along X
Axis and the Y-axis rate of decay will increase, this will cause imaging area range to reduce, therefore the angle needs of α, β are excellent by calculating progress
Change design.
Further, magnetic material 2 further includes the 4th magnetic material 2-2, is located at the first magnetic material 2-1 and pole plate 3
Between, and around one circle of the inside of the formed circumference of the second magnetic material 2-3 and third magnetic material 2-4 arrangement, magnetic aligning
It is identical as the first magnetic material 2-1, it can be further improved magnetic field strength in this way.
Pole plate 3 is located on the first magnetic material 2-1, the circle that the second magnetic material 2-3 and third magnetic material 2-4 are formed
It is all intermediate.The inner surface of pole plate 3 towards patient space are equipped with concentric compensation ring 6 and stretch ring 5, compensate ring 6 and stretch ring 5
It is bulge loop, is higher than polar board surface, wherein compensation ring 6 is located inside stretch ring 5, the middle position in pole plate inner surface；It draws
It stretches ring 5 and is located at pole plate inner surface edge, close to grading ring 4；And groove is additionally provided between compensation ring 6 and stretch ring 5.Stretch ring 5,
It compensates ring 6 and groove is one.
Yoke 1 includes plane yoke 1-1 and circumference yoke 1-2, and plane yoke 1-1 is located at the second magnetic material 2-3 and the
The circumference bottom surface that three magnetic material 2-4 are formed, circumference yoke 1-2 are wrapped in the periphery.So as to preferably by the second magnetic
Property material 2-3, third magnetic material 2-4 magnetic field imported into yoke 1, play better supporting role
Grading ring 4 is located on pole plate 3, lower than the circumference that the second magnetic material 2-3 and third magnetic material 2-4 is formed, shimming
Ring 4 is passing in and out direction with symmetrical two perforations notch along patient, and the height of notch is less than or equal to 4 height of grading ring, notch
Thickness be equal to the thickness of grading ring 4, and corresponding magnetic material 2 and yoke 1 also install downwards shape in corresponding gap position
At notch, so that guaranteeing can be with the increase of patient space.The notch is designed using step, and the place of interference does not add with patient space
It is high.Further, grading ring 4 is additionally provided with the compensation shimming 4-2 of arcuation, fits in the grading ring of the two sides of notch and notch
Inner wall, the magnetic field imaging area range of X-direction and Y-direction to solve to may cause with the use of notch grading ring is inconsistent to ask
Topic.
In a specific embodiment, magnet such as Fig. 6-7 designs magnet strength 0.3T, available patient space's diameter
710mm.Using four-column type structure, open angle about 80%.
Wherein, plane yoke 1-1, circumference yoke 1-2, pole plate 3, grading ring 4 compensate shimming 4-2 by high magnetic conduction material
Material is made, and the higher material magnet overall weight of magnetic conductivity is lower, and material cost is higher, and the present embodiment uses electrical pure iron material
Material.
Magnetic material 2, the first magnetic material 2-1 magnetic aligning direction are axially upwards.The second magnetic aligning side magnetic material 2-3
To with axially upwards be in 70 ° of angles.Third magnetic material 2-4 magnetic aligning direction with axially upwards be in 60 ° of angles.For convenience of processing
Dress installation, circumference yoke 1-2, the second magnetic material 2-3, third magnetic material 2-4 are designed as rectangle, are combined into one around shimming
Approximate annulus shape dress, calculating unilateral side magnetic pole the second magnetic material 2-3 points by optimization is 34 pieces, and third magnetic material 2-4 points are 8
Block.First tri- kinds of orientation magnetic material weight ratio of magnetic material 2-1, the second magnetic material 2-3, third magnetic material 2-4 are about
For 10:7.5:1.5.Also approximation is divided into multiple rectangular blocks and is spliced the 4th magnetic material 2-2 as a same reason, can increase field strength about
80Gs。
On pole plate 3, stretch ring 5, compensation ring 6 and groove are one, wherein stretch ring 5 thickness 10mm, width 50mm,
Ring 6 is compensated with a thickness of 6mm, width 100mm, material selection silicon steel sheet stack piece material is recessed between stretch ring 5 and compensation ring 6
Groove depth 10mm, width 10mm are located at and are biased to the compensation position the about 25mm of ring 6.
4 notch of grading ring is designed using step, and cut height is about the 4/5 of grading ring height, i.e., indentation, there is remaining
The ratio of grading ring height and grading ring height itself is about 1:4, corresponding, the magnetic material 2 and circumference yoke 1-2 of indentation, there
Also corresponding missing forms notch.Shimming 4-2 is compensated for compensating due to the inconsistent bring circumferencial direction magnetic of grading ring height
Field error, compensates shimming 4-2 thickness 15mm, and angle is 90 degree.
Using plate designs of the invention, in the imaging region of the magnet magnetic field drop point from magnetic field center positional distance by
About 200mm is expanded to about 230mm, and the product that final design goes out, imaging area range 420mm*420mm*380mm(X*Y*
Z), magnet performance is suitable with conventional magnet, and overall weight is less than 17 tons.
Magnet design of the invention can be not only used for four rod structures, also can be applied to twin columns, the other structures shape such as C-shaped
Formula, it is only necessary to which the variation for considering mechanical strength influences Magnetic Field Design result little.
It is to combine permanent-magnet to be illustrated electrode plate structure of the invention, but pole plate of the invention is not limited to permanent magnetism above
Magnet, can be used for often leading or superconducting magnet.Often lead or superconducting magnet in, be using often lead or superconducting coil replace permanent magnetism
Material generates magnetic field, is imaged using the vertical magnetic field between two coils, to make imaging area magnetic field reach imaging requirements, equally
It is provided with grading ring, pole plate etc..Increase areas imaging can also be equally played using pole plate of the invention, guarantees magnetic field homogeneity
Effect, so as on an equal basis imaging range of condition under, magnet weight can be greatly reduced.
Obviously, various changes and modifications can be made to the invention without departing from essence of the invention by those skilled in the art
Mind and range.In this way, if these modifications and changes of the present invention belongs to the range of the claims in the present invention and its equivalent technologies
Within, then the present invention is also intended to include these modifications and variations.
Claims (10)
1. a kind of pole plate, which is characterized in that the inner surface of the pole plate towards patient space are equipped with concentric compensation ring and drawing
Ring is stretched, the compensation ring and stretch ring are bulge loop, wherein compensation ring is located inside stretch ring, the centre in the inner surface
Position；Stretch ring is located at the inner surface edge；And groove is additionally provided between compensation ring and stretch ring.
2. pole plate according to claim 1, which is characterized in that the compensation ring, stretch ring and groove are one.
3. pole plate according to claim 1, which is characterized in that the stretch ring is higher than compensation ring.
4. pole plate according to claim 1, which is characterized in that the compensation ring is anti-eddy current compensation ring.
5. pole plate according to claim 4, which is characterized in that the compensation ring is that silicon steel stretch ring or amorphous lamination are mended
Repay ring.
6. a kind of magnet for magnetic resonant imaging, including pole plate as described in any one in claim 1-5.
7. magnet for magnetic resonant imaging according to claim 6, which is characterized in that the magnet further includes yoke, magnetic material
Material, grading ring, the yoke inner surface are provided with a pair of upper and lower symmetrical magnetic material, the opposite interior table of the magnetic material
Pole plate is respectively equipped on face, the grading ring is separately fixed on the opposite inner surface of pole plate.
8. magnet for magnetic resonant imaging according to claim 7, it is characterised in that: the magnetic material respectively includes the first magnetic
Property material, the second magnetic material and third magnetic material, wherein the second magnetic material and third magnetic material arrange arc-shaped shape
At circumference, the first magnetic material is laid in the circumferential inner；The magnetic aligning of first magnetic material is axial, the second magnetism
The magnetic aligning of material and the axial direction are at α angle, and the magnetic aligning of third magnetic material and the axial direction are at β angle；The shimming
Ring is passing in and out direction with symmetrical two perforations notch along patient, and the height of the notch is less than or equal to grading ring height, institute
The thickness for stating notch is equal to the thickness of grading ring, and the yoke of the notch corresponding position, upper and lower magnetic material also corresponding vacancy
Form notch.
9. magnet for magnetic resonant imaging according to claim 8, which is characterized in that the magnetic material further includes the 4th magnetism
Material forms circle between the first magnetic material and pole plate, and around the second magnetic material and third magnetic material
One circle of inside arrangement in week, magnetic aligning are identical as the first magnetic material.
10. magnet for magnetic resonant imaging according to claim 8, which is characterized in that the grading ring is additionally provided with the benefit of arcuation
Shimming item is repaid, the grading ring inner wall of the two sides of the notch and notch is fitted in.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811641077.1A CN109674472A (en) | 2018-12-29 | 2018-12-29 | Pole plate and magnet for magnetic resonant imaging with the pole plate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811641077.1A CN109674472A (en) | 2018-12-29 | 2018-12-29 | Pole plate and magnet for magnetic resonant imaging with the pole plate |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109674472A true CN109674472A (en) | 2019-04-26 |
Family
ID=66190294
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811641077.1A Pending CN109674472A (en) | 2018-12-29 | 2018-12-29 | Pole plate and magnet for magnetic resonant imaging with the pole plate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109674472A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109659110A (en) * | 2018-12-29 | 2019-04-19 | 佛山瑞加图医疗科技有限公司 | Grading ring and magnetic resonance magnet with the grading ring |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5345208A (en) * | 1993-05-26 | 1994-09-06 | General Electric Company | Pole face design for a C-shaped superconducting magnet |
| US20030011455A1 (en) * | 2001-07-16 | 2003-01-16 | Hitachi, Ltd. | Magnet, a method of adjustment of magnetic field and a magnetic resonance imaging apparatus |
| CN1548982A (en) * | 2003-05-23 | 2004-11-24 | 西门子（中国）有限公司 | Magnetostatic field regulating method in magnetic resonance equipment and magnetostatic field generating apparatus thereof |
| CN1711964A (en) * | 2004-06-22 | 2005-12-28 | 中国科学院电工研究所 | Magnet polar plate of magnetic resonance |
| CN209644899U (en) * | 2018-12-29 | 2019-11-19 | 佛山瑞加图医疗科技有限公司 | Pole plate and magnet for magnetic resonant imaging with the pole plate |
-
2018
- 2018-12-29 CN CN201811641077.1A patent/CN109674472A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5345208A (en) * | 1993-05-26 | 1994-09-06 | General Electric Company | Pole face design for a C-shaped superconducting magnet |
| US20030011455A1 (en) * | 2001-07-16 | 2003-01-16 | Hitachi, Ltd. | Magnet, a method of adjustment of magnetic field and a magnetic resonance imaging apparatus |
| CN1548982A (en) * | 2003-05-23 | 2004-11-24 | 西门子（中国）有限公司 | Magnetostatic field regulating method in magnetic resonance equipment and magnetostatic field generating apparatus thereof |
| CN1711964A (en) * | 2004-06-22 | 2005-12-28 | 中国科学院电工研究所 | Magnet polar plate of magnetic resonance |
| CN209644899U (en) * | 2018-12-29 | 2019-11-19 | 佛山瑞加图医疗科技有限公司 | Pole plate and magnet for magnetic resonant imaging with the pole plate |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109659110A (en) * | 2018-12-29 | 2019-04-19 | 佛山瑞加图医疗科技有限公司 | Grading ring and magnetic resonance magnet with the grading ring |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107110931B (en) | Ferromagnetic enhancement system for magnetic resonance imaging and method of providing the same | |
| US7567083B2 (en) | Superconductive magnetic apparatus for magnetic resonance imaging unit | |
| US9588198B2 (en) | Open-type nuclear magnetic resonance magnet system having an iron ring member | |
| US11422213B2 (en) | Ferromagnetic frame for magnetic resonance imaging | |
| CN102860828B (en) | MR imaging apparatus | |
| US6529005B1 (en) | Device for homogenizing a magnetic field | |
| CN209644899U (en) | Pole plate and magnet for magnetic resonant imaging with the pole plate | |
| JPH07106153A (en) | C-shaped superconductive magnet | |
| US6498488B2 (en) | Magnetic resonance imaging apparatus | |
| CN109659110A (en) | Grading ring and magnetic resonance magnet with the grading ring | |
| CN109674472A (en) | Pole plate and magnet for magnetic resonant imaging with the pole plate | |
| JP4536726B2 (en) | Static magnetic field generator for magnetic resonance apparatus and static magnetic field adjustment method for magnetic resonance apparatus | |
| GB2315127A (en) | Open-access MRI magnet with improved homogeneity | |
| CN209232530U (en) | Grading ring and magnetic resonance magnet with the grading ring | |
| EP0609604A1 (en) | Magnetic field generation device of use in superconductive type MRI | |
| JP4886482B2 (en) | Superconducting magnet apparatus and nuclear magnetic resonance imaging apparatus | |
| JP2007159741A (en) | Magnetic resonance imaging apparatus and electromagnet device | |
| CN109696644A (en) | A kind of magnet for magnetic resonance imaging | |
| JP6001499B2 (en) | Magnetic resonance imaging system | |
| CN109085519A (en) | Superconducting magnet magnetic field shimming system and method | |
| CN113009394B (en) | Static magnetic field generating device | |
| CN210639271U (en) | Shimming ring for magnetic resonance | |
| JP2005087229A (en) | Split type magnet and nuclear magnetic resonance imaging device | |
| US11320504B2 (en) | Open-type magnetic resonance imaging apparatus | |
| WO2016136383A1 (en) | Magnetic resonance imaging apparatus |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |