瑞士专利CH708241B1 NMR probe head with improved centering of the sample tube.

专利PDF首页>>瑞士专利

专利附录

专利说明

权利要求

类似技术

同族专利

引用文献

法律状态

优先权

专利摘要:
The invention relates to an NMR probe head (3) with a coil system (9) fixed radially relative to the sample head and a radial centering device of a sample tube (4) with two axially spaced centering devices for exclusively radial centering of the sample tube, wherein a first centering device (5) is arranged above the receiving coil system and all centering devices are radially fixed, characterized in that at least one further centering device (6) axially above the coil system with axial distance (d) above the first centering device is arranged, which is selected and the size and the geometric shape the passage openings in the centering devices are designed such that the first in cooperation with the further centering device restricts the radial range of motion of the sample tube to the extent that the test tube endangers one eten space region (7), which extends axially in the region of the receiving coil system and radially within the same, during the entire transport process of the sample tube in its measuring position can not touch, and that the further centering device is connected to the probe head. Thus, the transport of the sample tube from entry into the sample head to its measurement position is controllable so that probe components in the hazardous area of the sample tube are not damaged.
公开号:CH708241B1
申请号:CH00934/14
申请日:2014-06-19
公开日:2017-12-29
发明作者:Schmidig Daniel；Al Adwan-Stojilkovic Danijela；Wilhelm Dirk
申请人:Bruker Biospin Ag；
IPC主号:

专利说明:

Description: [0001] The invention relates to an NMR (nuclear magnetic resonance) probe head with an NMR coil system arranged around a preferably vertical z-axis and a device for radial centering of a measuring tube filled, unilaterally closed elongated sample tube relative to the z-axis. wherein the NMR coil system is fixed relative to the NMR probe head radially with respect to the z-axis, wherein at least two in the axial direction of the z-axis spaced centering means are provided with through holes for the sample tube for exclusively radial centering of the sample tube, of which at least one first centering device is arranged in the z-direction above the NMR coil system, and wherein all centering devices are fixed radially with respect to the z-axis.
Such an arrangement is known for example from US 6,563,317 B2 (reference [1]).
Background of the invention NMR spectroscopy is a powerful method of instrumental analysis. In this case, RF (= radio-frequency) pulses are radiated into a test sample, which is in a strong, static magnetic field, and the HF reaction of the Measurement sample is measured. The information is obtained integrally over a certain range of the test sample, the so-called active volume.
The measuring sample usually consists of a cylindrical sample tube containing the solid or liquid substance. The tube may have a circular, oval or rectangular cross-section. It is closed at least on the side with which it first penetrates into the probe head. Typically, the closed side is rounded. The sample tube is typically in a spinner. It can either be firmly attached to the spinner or loose in the spinner. Sample tubes and spinners are transported from outside the magnet into the probe head using a transport system. In the following it is assumed that the insertion opening is at the top of the sample head and the sample tube is inserted from above into the sample head. However, it is also conceivable to introduce the sample tube from below into a designated opening in the probe head. This case is analogous to the above and is not explicitly described for reasons of clarity. When the sample tube is in the measurement position, the spinner is inside the turbine. The turbine allows rotation of the sample tube.
In the measuring position, the sample tube is surrounded by one or more NMR coils. The innermost NMR coil has an inner diameter which is as little as possible larger than the outer diameter of the test sample, since the fill factor and thus the sensitivity of the NMR coil depends on the inner diameter and decreases with increasing inner diameter.
Various fragile probe head components can be arranged around the sample tube in the measuring position. This can be, for example, the innermost NMR coil or even a glass tube carrying the innermost NMR coil. Generally speaking, there is talk of a hazardous area around the sample tube in the measuring position. During the transport process of the sample tube into the measurement position, a collision with such fragile components that are located in the hazardous area, usually involves a complex repair of the probe head.
In reference [1], the sample tube is centered in the measuring position by two radially acting centering devices located axially above and below the coil. The centering devices are rigidly connected to the carrier device of the receiving coil. In addition, an exclusively axial positioning is provided. This can be done either below the receiving coil by a stop or above the receiving coil within a modified spinner using a mounting sleeve.
DISADVANTAGES OF THE PRIOR ART [0008] The prior art centering devices (see references [1] and [2] and references cited therein) are intended solely to accurately and safely control the position of the sample tube in the measuring position. However, during transport to the measuring position, accurate guidance of the sample tube is not achieved at all times. If the sample tube is still above the measuring position, in particular the lower end of the sample tube can move radially relatively far away from the sample head axis. In the process, components of the probe head which are located in an endangered area may be damaged during the transport process into the measuring position.
Also, a low probability of such damage during insertion of the sample tube into the probe head is extremely disadvantageous if the NMR spectrometer is operated as a high-throughput analysis system. Automatic sample tube changers and filling robots make it possible to carry out a large number of measurements on different samples in a very short time. In this case, the combination of low probability of damage with the multiplicity of sample changes can also lead to an unacceptable failure rate.
OBJECT OF THE INVENTION The present invention is based on the object to modify an NMR probe head of the type defined above with the simplest possible technical measures so that the above enumerated disadvantages are largely avoided, the transport of the sample tube from entering the Probe should be controlled to the measuring position so that probe components in an endangered area within the probe head of the sample tube can not be damaged.
In order to keep the downtime as low as possible, especially when using an automatic sample tube changer, a very high level of security in the individual processes is sought. A contact of the probe head in the hazardous area through the sample tube should therefore be completely excluded with certainty.
Another object of the present invention is to allow a quick change of the sample tube without thereby risking a significantly shortened life of the probe head.
BRIEF DESCRIPTION OF THE INVENTION This complex object is achieved in an astonishingly simple and effective manner by virtue of the fact that, in a generic NMR probe head with the features defined at the outset, at least one further centering device is located axially above the NMR coil system and either above or below the first Centering device is arranged such that the axial distance of the two centering devices are selected and the size and the geometric shape of the through holes in the centering devices are designed such that the first centering device in cooperation with the further centering device so the radial movement of the sample tube relative to the z-axis far narrows that the sample tube a predetermined hollow cylindrical space region, which is axially with respect to the z-axis in the region of the NMR coil system and optionally also above and / or below it so as radially extends at least partially within the NMR coil system (and is also sometimes referred to below as "vulnerable area"), during the entire process of transporting the sample tube into its measuring position in the NMR probe head can not touch, and that the further centering with is mechanically connected to the NMR probe head.
The inventive NMR probe head has a system of guides, which has at least two radially acting positioning, which are located between the insertion opening of the NMR probe head and the magnetic center, wherein the radially acting guides are sufficiently far apart in the z direction and restrict the radial movement of the sample tube so that the sample tube can not touch the hazardous area during the entire process of transporting the sample tube in the measuring position. The two radial guides also cause a centering of the sample tube in the measuring position. The centering in the measuring position can be supplemented by a further radial positioning below the coil in their effect. However, this additional guidance is effective only during the transport of the sample tube into the measuring position at the end of the process. So it does not serve to protect the endangered area, but only for centering in the measuring position.
In order to achieve optimum centering of the sample tube, the two radial guides above the NMR coil with the carrier device of the NMR coil can be firmly connected. As a result, tolerances in the relative positioning of sample tube and NMR coil can be minimized.
The sample tube is positioned axially either by a stop below the NMR coil or by abutment of the spinner to the turbine.
Advantages over the Prior Art With the aid of the system of guides according to the invention, it is achieved that the sample tube can not touch the hazardous area at any time during the entire transport process from outside the magnet into the probe head and finally into the measuring position. This avoids costly and expensive repairs of these sensitive components of the NMR probe heads. At the same time, the inner diameter of the NMR coil can be chosen sufficiently small, so that the fill factor and thus the NMR sensitivity can be optimized.
At this point, it is expressly understood that while in the description of the present invention as well as in the claims - the sake of linguistic simplicity - always from a "vertical z-axis" and axial positions "above" or "below" However, the advantages of the invention can also be achieved in NMR systems with a horizontal or oblique z-axis. The specified axial positions must then no longer necessarily be "above" or "below" the NMR coil system, but possibly also "right" or "left" next to it. In any case, gravity plays a minor role in the operation of the present invention.
PREFERRED EMBODIMENTS OF THE INVENTION A class of embodiments of the NMR probe head according to the invention is advantageous, in which a cylindrical tube is arranged in the hollow-cylindrical space region, which encloses the sample tube in its measuring position. The cylindrical tube serves as a holder for the radially innermost NMR coil. It is typically a good electrical insulator that produces low losses for high frequency currents (e.g., glass-ceramic, peek, fused silica, sapphire). In order to achieve the highest possible fill factor and thus a high signal-to-noise ratio (= SNR), the inner diameter of the NMR coil is chosen as little as possible larger than the outer diameter of the sample tube. Therefore, it is advantageous if the cylindrical tube has the smallest possible wall thickness. However, the wall thickness significantly affects the strength of the cylindrical tube so that thin tubes are very susceptible to collisions with the sample tube. The arrangement according to the invention with its two radial guides ensures that the sample tube can not touch the cylindrical tube at any time during the insertion process into the measuring position. Thus, a violation of the cylindrical tube is excluded. Elaborate and expensive repairs of the probe head are thus avoided.
Particularly preferred is a class of alternative embodiments, in which in the hollow cylindrical space region with respect to the z-axis radially innermost NMR coil of the NMR coil system and / or a support structure for this innermost NMR coil is / are arranged. In this arrangement, the inner diameter of the NMR coil is smaller than that with a cylindrical tube. Thus, the fill factor and finally the SNR are higher than in the case described above. Since the NMR coil is a very expensive, expensive and prone part of the probe head, the protection of this coil from collisions with the coil tube is urgent. This is achieved by means of the guides according to the invention. Because the radial centering devices are arranged so that a contact of the sample tube is excluded with the innermost NMR coil.
In preferred developments of this class of embodiments, the carrier structure for the innermost NMR coil is arranged in the hollow cylindrical space region, and the first centering device extends at least partially radially between the support structure and the sample tube in its measuring position. The arrangement of the first centering device within the support structure, a very narrow inner diameter of the centering device is achieved. The narrower the inner diameter of the centering device, the more accurate the sample tube can be guided radially. Together with the second centering device, an extremely accurate guidance of the sample tube during introduction into the measuring position is achieved, which in turn prevents contact of the sample tube with the support structure of the innermost NMR coil.
Also preferred is an embodiment of the inventive NMR probe head, which is characterized in that at least one centering device is geometrically designed in its cross-section that tempering between the sample tube in the measuring position and the centering devices can flow through, and that the entire Blocking the Temperiergasstroms by the centering devices in a cross-sectional plane perpendicular to the z-axis is a maximum of 70%. An optimal temperature control of the sample tube is carried out by a Temperiergasstrom flowing directly on the surface of the sample tube along. In contrast, the centering device should have the smallest possible inner diameter in order to achieve optimum guidance. Thus, the centering device generates, if it is close to the sample tube with a narrow inner diameter, a blocking of Temperiergasstroms. This blocking should not be too large, so that the flow resistance and thus the pressure loss can be kept small.
A further development of this and / or the previously described embodiment provides that the first centering device, a radially inner guide, a preferably acting as HF (= high frequency) shielding cylindrical tube and an upper stop edge for abutment on the upper face of a cylindrical Coil covers glass. Thus, a dual function of RF shielding and centering is achieved, with the advantage of reducing the number of parts required, which costs can be saved.
Further advantageous variants provide that the first centering device is provided with a plurality of axially extending in the axial direction along the z-axis radial recesses in a radially inner guide and / or arranged along the z-direction slots. The recesses or slots allow the Temperiergasstrom flow along the sample tube through the inner guide. They can be chosen so that the blocking and thus the flow resistance is sufficiently small, which ultimately leads to an efficient temperature control of the sample tube.
These variants can also be further developed in that are provided on lamellae between the slots in the radial direction of increased cams, which are dimensioned so that the first centering device when inserted into the support structure for the relative to the z-axis radially innermost NMR coil of the NMR coil system clamped in the radial direction. For a close connection of the first centering device is achieved with the support structure. Since the support structure directly carries the receiving coil, thus an advantageous centering of the sample tube is made relative to the receiving coil. In addition, a displacement or rotation of the centering device under the effect of the Temperiergasstroms can be prevented by the radial strain in the support structure.
A further preferred embodiment of the inventive NMR probe head is characterized in that a third centering device is arranged at an axial distance in the z-direction above the first centering device and below the further centering device. With a third centering device, the sample tube can be guided during the entire insertion process up to the measuring position with extremely high accuracy.
Further preferred embodiments of the invention are characterized in that at least one centering device is arranged axially below the NMR coil system. This additional radially acting centering device comes at the end of the insertion process of the sample tube in the measurement position to fruition. It causes the sample tube in the measuring position is very well guided radially.
In further advantageous embodiments, at least one positioning device for axial positioning of the sample tube is provided, which can be located in the operating position either below or above the NMR coil system.
These embodiments can be further developed in that the positioning device is arranged axially below the NMR coil system and comprises a stop member on which the sample tube is seated in the measuring position. The radial centering devices must be supplemented by an axial centering, which takes place either via an abutment of the spinner in the turbine or through an axial centering below the NMR coil. By means of the axial centering, due to the spatial proximity to the NMR coil, a very accurate positioning of the sample tube relative to the magnetic center of the NMR coil in the Z direction can be achieved. This is important so that the magnetic field of the NMR coil coincides with the relevant region of the sample tube, the relevant region being that in which the NMR signals are recorded. It is called "active sample volume".
Embodiments of the inventive NMR probe head are also advantageous, in which the first centering device and the further centering device and optionally an axially below the NMR coil system centering device are mechanically rigidly interconnected, in particular via connectors and / or by attachment to a support structure for the NMR coil system. With the aid of the rigid connection, the tolerances between the individual parts, namely the support structure, the receiving coil and the centering devices, can be well controlled. Thus, a very good centering of the sample tube relative to the receiving coil can be achieved.
Another preferred class of embodiments of the invention is characterized in that the first centering device and / or the further centering device has a funnel-shaped passage opening for receiving the sample tube. The funnel shape allows for good guidance of the sample tube upon initial entry into the respective centering devices.
Embodiments of the inventive NMR probe head, in which the axial distance between the first centering device and the radially innermost NMR coil of the NMR coil system with respect to the z-axis is smaller than twice the radial diameter of the sample tube, prove particularly useful in practice , The smaller the distance between the first centering device and the NMR coil, the more accurate the sample tube can be guided in the radial direction.
Particularly advantageous is also a class of embodiments of the invention, which are characterized in that exactly one first centering device and exactly one further centering device are located axially above the NMR coil system, wherein the areas of the centering of which the sample tube is effectively guided in the z-direction each have an axial extent of 0.05D to 0.6D, where D denotes the radial diameter of the sample tube. The range in which the end of the sample tube during the transport process can move from the desired position is determined by the axial distance between the two centering devices and their accuracy, but not by the length of the guide of a single centering device. It is therefore advantageous to keep the axial extent of these guides small in order, for example, to reduce the resistance to the tempering gas flowing between the centering device and the sample tube.
In further preferred embodiments, at least one of the axially arranged above the NMR coil system centering means is made of a material having a hardness which is substantially smaller than the hardness of the materials from which the sample tube is made, in particular smaller than that Hardness of borosilicate glass or quartz glass. Since the sample tube comes into contact with the guide means during insertion into the measurement position, a softer material than the sample tube material is desirable. This prevents the sample tube from being damaged when it hits the guide devices. Since the sample tube performs an axial movement along the centering device when inserted into the measuring position, there is also the risk of the formation of scratches on the sample tube. This risk is avoided by choosing a material with a lower hardness than that of the sample tube.
Also advantageous are embodiments in which at least one of the axially arranged above the NMR coil system centering devices consists of a material whose surface has a conductivity> 107 S / m. This high conductivity of the centering device allows the centering device can also be used for RF shielding off. The RF shielding is important to guide the magnetic fields of the NMR coil and to limit in the Z direction. The dual function of the inventive component leads to significant savings in the production costs of the sample heads.
Particularly preferred is an embodiment of the inventive NMR probe head, wherein at least one of the axially arranged above the NMR coil system centering means has an axial length of at least one radial diameter D of the sample tube and at an axial distance to the Axis radially innermost NMR coil of the NMR coil system is positioned, which is smaller than the radial coil diameter of the innermost NMR coil. The axial distance of the positioning device to the radially innermost NMR coil is kept as small as possible in order to achieve a good radial guidance of the sample tube.
Advantageous developments of these two abovementioned embodiments are characterized in that the centering devices are contacted with an HF shielding tube of the NMR probe head RF-moderately electrically. The contacting with the electrically conductive centering device with the probe head mass, which is formed by the shielding tube, allows an improved shielding of the probe head against externally penetrating RF interference signals.
Alternatively or additionally, in other developments, the centering means may be formed such that within the centering means no path exists, which encloses the sample tube in its measuring position. This development can be formed for example by a hollow cylindrical structure with a slot in the axial direction along the generatrix. Frequently, in NMR experiments, gradient fields are applied over the active volume. These are variable, often inhomogeneous in the z-direction magnetic fields, which are superimposed on the static BO field. In conductive structures, unwanted currents are induced by these gradient fields. By now standing perpendicular to these gradient fields conductor loops are prevented, a large part of these currents is suppressed.
Also preferred are embodiments of the inventive NMR probe head, wherein at least one of the axially arranged above the NMR coil system centering means consists of a material which has an electrical conductivity <10 "8 S / m. It is advantageous if the first centering device is made of the same insulating material as the support structure for the NMR coils. Then, the centering device and the support structure can be manufactured in one step, which leads to a significant cost drop. This type of construction is particularly advantageous if no RF shielding is provided in the vicinity of the radially innermost NMR coil.
Likewise, embodiments of the invention are advantageous in which at least one of the axially arranged above the NMR coil system centering devices consists of a material having a magnetic susceptibility with amount <1.0 ppm. For NMR spectroscopy, local strains of the magnetic field of the order of a millionth part (1 ppm) of the magnetic field strength are already disturbing and possibly can no longer be reduced to an acceptable level by shimming. For the distortion of the magnetic field, the susceptibility of the materials used, the distance to the active volume and the geometry of the components are decisive. Since the centering devices are near the NMR receiver coil, the susceptibility values directly affect the quality of the NMR signals. The greater the magnitude of the susceptibility values, the more the NMR signals are disturbed. Therefore, small susceptibility values of the centering devices are preferred. Finally, another specific embodiment of the NMR probe head according to the invention is characterized in that the temperature control gas flowing around the sample tube does not flow between the centering device and the sample tube in at least one of the centering devices, but is conducted through exhaust air holes offset radially away from the z axis. It is e.g. advantageous to guide the Temperiergasstrom through the first axially to the innermost NMR coil next centering device, since this centering device is usually in the range in which the sample tube is filled with a sample liquid. The second centering device farther from the innermost NMR coil is i.d.R. in the area where the sample tube is filled with a gas. In this area, there is a smaller heat transfer from the tempering gas flow to the sample. Therefore, in this area, no temperature control gas flow applied to the sample tube is necessary.
The scope of the present invention also includes an NMR measuring arrangement with an inventive NMR probe head of the type described above, which also includes an NMR magnet system, a shim system, a turbine and a device for transporting a sample tube from outside the NMR range. Magnet system to the measuring position of the sample tube in the NMR probe head comprises. The centering devices according to the invention are particularly effective in the overall system of probe head, NMR magnet and transport device, since this combination allows automatic replacement of sample tubes, e.g. are very important in high-throughput NMR applications. The inventive arrangement makes an important contribution to these applications because it prevents damage to the probe head during insertion of the sample tube.
Further advantages of the invention will become apparent from the description and the drawings. Likewise, according to the invention, the above-mentioned features and those which are still further developed can each be used individually for themselves or for several in any desired combinations. The embodiments shown and described are not to be understood as exhaustive enumeration, but rather have exemplary character for the description of the invention.
DETAILED DESCRIPTION OF THE INVENTION AND DRAWING The invention is illustrated in the drawing and will be explained in more detail by means of exemplary embodiments. Show it:
1a shows an embodiment of the inventive centering device for guiding the NMR sample tube in the NMR probe head in a schematic vertical section;
FIG. 1b shows the introduction of the NMR sample tube into the NMR probe head with centering device according to the invention according to FIG. 1a; FIG.
Figure 2a is a schematic vertical sectional view of a positioning of the NMR sample tube in a prior art NMR probe head.
2b shows the introduction of the MMR sample tube in the NMR probe head according to the prior art according to Figure 2a in a schematic vertical section ..;
3 shows an embodiment of the NMR probe head according to the invention, in which the sample tube is guided axially through a stop and radially through a further centering device located axially below the NMR coil system;
4 shows an embodiment of the inventive NMR probe head in which the sample tube is guided radially through three centering devices above the NMR coil system;
5 shows an embodiment of the inventive NMR probe head, in which the upper centering devices are rigidly connected to one another via connecting pieces;
6 shows an embodiment of the inventive NMR probe head, in which the upper centering devices and the lower centering device are rigidly connected to one another via connecting pieces;
7 shows an embodiment of the inventive NMR probe head, in which the centering devices are designed such that temperature control gas can flow between the sample tube and the centering devices;
8 shows an embodiment of the centering device according to the invention, in which the centering device closest to the NMR coil is integrated into an RF shield above the NMR coil;
9 shows a schematic cross section through an embodiment of the guide according to the invention in a plane perpendicular to the z-axis with a geometric shape suitable for the passage of the temperature control gas with a plurality of radial recesses extending in the axial direction along the z-axis in a radially inner centering device;
10a shows an embodiment of the centering device according to the invention with slots arranged along the z-direction and raised lugs arranged on lamellae between the slots in the radial direction for clamping on the coil carrier structure;
10b shows a schematic vertical section through one half of the embodiment according to FIG. 10a during the introduction of the centering device onto the coil carrier structure;
FIG. 10c, like FIG. 10b, but with the guide in its end position on the coil carrier structure; FIG. and
11 the area of a centering device which can touch the sample tube in the measuring position.
The invention is concerned with the damage-free insertion of NMR sample tubes in their measurement position in an NMR probe head.
The most commonly used sample tubes in NMR are made of borosilicate (glass), round cylindrical and have an outer diameter of 5 mm and a total length of about 7 inches (about 18 cm). The active volume from which the NMR measurement information is obtained is located in the lower third of the tube and typically extends about 25 mm in length of the sample tube. The active volume is surrounded by NMR coils (more precisely: RF coils), which excite the atoms in this region via an excitation field (B1 field) orthogonal to the main field (BO field). In the active volume, the excited atoms emit a weak alternating magnetic field, which is again received by corresponding NMR coils.
The innermost NMR coil has an inner diameter which is as little as possible larger than the outer diameter of the measurement sample, since the fill factor and thus the sensitivity of the NMR coil depends on the inner diameter. The
Sensitivity drops with increasing inside diameter. In the measuring position, the sample tube is surrounded by a vulnerable area, this can be formed by the coil itself or by a support tube which carries the coil.
There are also NMR tubes with other outside diameters such as 1 mm, 1.7 mm, 8 mm, 10 mm, 15 mm and 20 mm in use. These have different active volumes to the tubes with 5 mm outer diameter. In addition to the approximately cylindrical shape, other cross sections (for example elliptical, rectangular, one-sided flattened) are also common. The end of the sample tube, which is first inserted into the probe head, usually has a rounding.
The sample tube is typically in a spinner. It can either be firmly attached to the spinner or loose in the spinner. The sample tube is transported from outside the magnet to the measuring position in the sample head by means of a transport system. When the sample tube is in the measurement position, the spinner is inside the turbine. The turbine allows rotation of the sample tube.
In the prior art, the transport of the sample tube into the measurement position is not fully controlled at all times. This may cause components in the hazardous area surrounding the sample tube in the measurement position to be damaged when the sample tube is inserted into the sample head. This entails costly and expensive repairs.
The invention solves this problem by the sample tube is controlled during the entire transport process from outside the sample head to the measuring position so that the vulnerable area can never be touched by the sample tube.
The invention is characterized in that there are at least two radially acting guides above the NMR coils. The radial guides are sufficiently far apart in the z-direction so that the sample tube can not touch the hazardous area.
Fig. 1a schematically illustrates an embodiment of the NMR probe head according to the present invention, as described in detail below, with a device for guiding the sample tube.
The sample tube 4 is received by a spinner 2, which rests with an oblique outer edge in a turbine 1. The sample tube 4 is located in its measuring position in an NMR probe head 3. It is radially surrounded by a predetermined hollow cylindrical space area 7 (hereinafter also "endangered area"), which by means of the invention before a collision with the sample tube 4 and thereby caused damage is to be protected. If, as shown in Fig. 1a, the sample tube 4 is in its measuring position, then centered the system of radial guides with centering devices 5 and 6, which are arranged in the z direction above a NMR coil system 9, the sample tube 4th
Fig. 1 b shows how the sample tube 4 is introduced in the inventive arrangement in the probe head. The system of radial guides 5, 6 causes the sample tube 4 during insertion can not touch the vulnerable area 7.
Fig. 2a shows the prior art, wherein the sample tube 4 is radially centered by the upper centering 5 and the lower centering 8 in the measuring position. However, the centering 8 only works when the sample tube 4 is already in the measuring position. The axial positioning is carried out by stops of the spinner 2 to the turbine 1, wherein an axially disposed below the sample tube 4 stop member 11 provides additional security for the axial stop in its measuring position, if no spinner 2 is present.
Fig. 2b shows how the prior art sample tube 4 is inserted into the probe head. In this case, the sample tube 4 can damage sample head components in the endangered area 7 by tilting with respect to the z-axis.
Fig. 3 shows how a sample tube 4 is guided without spinner in the inventive arrangement radially through the guides 5, 6 and in addition by the centering 8. The axial guidance is not carried out by the turbine, but only by the axial stop eleventh
Fig. 4 shows a system according to the invention of three radially acting guides 5, 5a, 6, which are all located above the vulnerable area 7. This arrangement is advantageous if the distance between the upper opening of the probe head 4 and the NMR coil is relatively large.
In Fig. 5, the upper radial guides 5 and 6 are firmly connected. This is done by a connector 12. In addition, the vulnerable area 7, e.g. can consist of an NMR coil carrier glass, connected via a further connector 13 fixed to the connector 12. The connecting pieces 12 and 13 may be made of one part. By connecting these parts, the influence of component tolerances is minimized. It is also possible that a guide is fixedly connected to an NMR coil carrier glass, whereby the further connecting piece 13 can be omitted.
In Fig. 6 and the lower centering 8 via a longer connecting piece 14 axially with the upper guides 5, 6 firmly connected. Again, a fixed radial connection 15 with the coil carrier glass or the NMR coil is possible.
Fig. 7 shows how a sample tempering gas flow past the sample tube 4 passes through the first centering device 5 'as well as through the further centering device 6'. The upper centering device 6 'must be designed in this case so that it does not increase the flow resistance for the Temperiergasstrom not unintentionally. The temperature of sample tubes 4 is e.g. in reference [4] and in references cited therein.
8, a first centering device 5 "with a radially inner guide 16 is formed directly at the lower end of an RF shield 18. This is located on the inside of a coil lens 17 which carries the NMR coil 9 ' Edge 19 prevents slippage of the RF shield 18. In this arrangement, a radial guide is fixedly connected to the bobbin 17.
Fig. 9 shows a cross section through the sample tube 4 perpendicular to the z-axis. The sample tube 4 is guided by the guide 16 'in the radial direction. The guide 16 'has periodic recesses in the circumferential direction through which the Temperiergasstrom can flow. The sample tube 4 is guided radially only at the points lying on the innermost radius. The recesses of the centering device 16 'are chosen so that the blocking of the flow is as small as possible.
The RF shield with first centering device 5 '' 'according to Fig. 10a is provided with cams 20 and slots 21. The cams 20 are slightly raised, i.e. they project outwardly from the RF shield 18.
When this RF shield 18 of the first centering device 5 '"is brought into the bobbin 17, as shown in Figures 10b and 10c, the cams 20 are pushed radially inward, which is easily possible due to the slots 21 The thickness of the cams 20 and the length and width of the slots 21 can be chosen so that the RF shield 18 can be inserted well into the bobbin 17 and at the same time seated sufficiently firmly are too large, otherwise the shielding effect of the RF shield 18 is impaired.
10 c shows the RF shield 18 of the first centering device 5 '"with cam 20 in the end position on the coil carrier glass 17th
Finally, FIG. 11 shows the region 22 of a centering device 5 "" which can touch the sample tube 4 in the measuring position. This area 22 has the axial length b.
LIST OF REFERENCES (1) Turbine (2) Spinner
(3) NMR probe head with outside diameter D (4) Sample tube (5; 5 '; 5 "; 5 5" ") first centering device, axially above the NMR coil system (6; 6) further centering device, axially above the NMR coil system as well as with axial
Distance d to the first centering device (5a) third centering device, with axial distances between the first and the other
Centering device (7) predetermined hollow cylindrical ("endangered") space area (8) additional centering device, axially below the NMR coil system (9; 9) NMR coil system (11) stop part for the sample tube in its operating position (12, 13; 14, 15 ) Connecting pieces (16; 16) radially inner guide (17) Cylindrical coil carrier glass (18) Cylindrical tube, preferably acting as HF shielding (19) upper stop edge

权利要求:
Claims (25)
[1]
(20) cams, increased in the radial direction (21) slots, arranged along the z-direction (22) portion of a guide device, the sample tube can touch in the measuring position (d) axial distance between the first and further centering device (b) axial length of Section 22 Reference List [1] M. Warden, R. Seydoux, D. Marek: US 6,563,317 B2; EP 1 239 296 B1; DE 10 111 672 C2 [2] D. Marek: US Pat. No. 6,466,019 B2; EP 1 124 137 B1; DE 10 006 324 C1 [3] K. Nagao; K. Nakagawa: US Pat. No. 3,525,928 [4] B. Grossniklaus, F. Rafia, M. Mayer, D. Wilhelm: US 2011/0 284 192 A1; EP 2 388 609 A1; DE 10 2010 029 080 B4 Claims
1. NMR probe head (3) with an arranged around a vertical z-axis NMR coil system (9; 9 ') and a device for radial centering of a filled with a measuring substance, one-sided closed elongated sample tube (4) relative to the z-axis in which the NMR coil system (9; 9 ") is fixed radially relative to the NMR probe head (3) with respect to the z-axis, at least two centering devices (5; 5 '; 5") being spaced from each other in the axial direction of the z-axis. ; 5 "'; 5a; 6; 6'; 8) are provided with through openings for the sample tube (4) for exclusively radial centering of the sample tube (4), of which at least one first centering device (5; 5 '; 5"; ") is arranged in the z-direction above the NMR coil system (9; 9 '), and wherein all centering devices (5; 5'; 5"; 5 "'; 5" "; 5a; 6; 6'; 8) are fixed radially with respect to the z-axis, characterized in that at least one further centering device (6; 6 ') ax ial above the NMR coil system (9; 9 ') and with axial distance (d) with respect to the z-axis to the first centering device (5; 5', 5 ", 5" ') is arranged such that the axial distance (d) selected and the size and the geometric shape the through openings in the centering devices (5; 5 '; 5 "; 5"'; 5 ""; 5a; 6; 6 ') are designed such that the first centering device (5; 5'; 5 "; 5" ') in cooperation with the further centering device (6, 6 ') the radial movement of the sample tube (4) relative to the z-axis so far narrows that the sample tube (4) has a predetermined hollow cylindrical space area (7), which axially with respect to the Z- Axis in the region of the NMR coil system (9; 9) and also above and / or below it and radially at least partially within the NMR coil system (9; 9 '), during the entire process of transporting the sample tube (4) into its Measurement position in the NMR probe head (3) can not touch, and that the other Ze ntrierungseinrichtung (6; 6 ') in the NMR probe head with the NMR probe head (3) is mechanically connected.
[2]
2. NMR probe head according to claim 1, characterized in that in the hollow cylindrical space region (7), a cylindrical tube is arranged, which encloses the sample tube (4) in its measuring position.
[3]
3. NMR probe head according to claim 1, characterized in that in the hollow cylindrical space region (7) with respect to the z-axis radially innermost NMR coil of the NMR coil system (9; 9 ") and / or a support structure for this innermost NMR Coil is / are arranged.
[4]
4. NMR probe head according to claim 3, characterized in that in the hollow cylindrical space region (7), the support structure for the innermost NMR coil is arranged, and that the first centering means (5 "; 5" ') at least partially radially between the support structure and the sample tube (4) extends in its measuring position.
[5]
5. NMR probe head according to one of the preceding claims, characterized in that at least one centering device (5; 5 '; 5 "; 5"; 5 ""; 5a; 6; 6'; 8) is configured geometrically in its cross section in that tempering gas can flow between the sample tube (4) in its measuring position and the centering devices (5; 5 "; 5"; 5 "; 5" "; 5a; 6; 6 '; 8), and that the entire blockage of the Temperiergasstroms by the centering means (5; 5 "; 5"; 5 "'; 5" "; 5a; 6; 6'; 8) in a cross-sectional plane perpendicular to the z-axis is a maximum of 70%.
[6]
6. NMR probe head according to claim 4 or 5, characterized in that the first centering device (5 "; 5" ') a radially inner guide (16; 16 "), preferably acting as a high-frequency shield cylindrical tube (18) and an upper stop edge (19) for abutment on the upper end face of a cylindrical bobbin glass (17).
[7]
7. NMR probe head according to one of claims 4 to 6, characterized in that the first centering device (5 "," 5 ") having a plurality of axially extending along the z-axis radial recesses in a radially inner guide (16) and / or is provided with slits (21) arranged along the z-direction.
[8]
8. NMR probe head according to claim 7, characterized in that on lamellae between the slots (21) in the radial direction increased cam (20) are provided, which are dimensioned so that the first centering device (5 ") when inserted into the Support structure for the respect to the z-axis radially innermost NMR coil of the NMR coil system (9, 9 ') braced in the radial direction.
[9]
9. NMR probe head according to one of the preceding claims, characterized in that a third centering device (5a) with axial spacing in the z-direction above the first centering device (5; 5 ', 5 "; 5"') and below the further centering device (6; 6) is arranged.
[10]
10. NMR probe head according to one of the preceding claims, characterized in that at least one centering device (8) is arranged axially below the NMR coil system (9; 9 ").
[11]
11. NMR probe head according to one of the preceding claims, characterized in that at least one positioning device for axial positioning of the sample tube (4) is provided, which can be located in the measuring position either below or above the NMR coil system (9; 9 ") ,
[12]
12. NMR probe head according to claim 11, characterized in that the positioning means axially below the NMR coil system (9; 9) is arranged and a stop member (11), on which the sample tube (4) is seated in its operating position.
[13]
13. NMR probe head according to one of the preceding claims, characterized in that the first centering device (5; 5 '; 5 "; 5"') and the further centering device (6; 6 ') and optionally a third centering device (5a) and / or an axially below the NMR coil system (9; 9) arranged centering device (8) are mechanically rigidly interconnected, in particular via connecting pieces (12, 13, 14, 15) and / or by attachment to a support structure for the NMR coil system (9; 9 ').
[14]
14. NMR probe head according to one of the preceding claims, characterized in that the first centering device (5; 5 '; 5 "; 5") and / or the further centering device (6; 6) and optionally a third centering device (5a) a having a funnel-shaped passage opening for receiving the sample tube (4).
[15]
15. NMR probe head according to one of the preceding claims, characterized in that the axial distance between the first centering device (5; 5 "; 5"; 5 "') and the NMR-coil of the NMR-axis which is radially innermost with respect to the z-axis Coil system (9; 9 ') is smaller than twice the radial diameter of the sample tube (4).
[16]
16. NMR probe head according to one of the preceding claims, characterized in that at least one of the axially above the NMR coil system (9; 9) arranged centering means (5; 5 "; 5"; 5 "'; 5 5a; 6; ) such that the region (22) of the centering device (5; 5 "; 5" '; 5 ""; 5a; 6; 6) which can touch the sample tube (4) in the measuring position has an axial position Extension (b) of 0.05 to 0.6 diameter D of the sample tube (4).
[17]
17. NMR probe head according to one of the preceding claims, characterized in that at least one of the axially above the NMR coil system (9; 9) arranged centering means (5; 5 "; 5"; 5 "'; 5 5a; 6; ') consists of a material which has a hardness which is smaller than the hardness of the materials from which the sample tube (4) is made, in particular smaller than the hardness of borosilicate glass or quartz glass.
[18]
18. NMR probe head according to one of the preceding claims, characterized in that at least one of the axially above the NMR coil system (9; 9) arranged centering means (5; 5 "; 5"; 5 "'; 5 5a; 6; ') consists of a material whose surface has a conductivity> 107 S / m.
[19]
19. NMR probe head according to claim 18, characterized in that at least one of the axially above the NMR coil system (9; 9) arranged centering means (5; 5 "; 5"; 5 "; 5 '"'; 5a; 6; 6 ") has an axial length of at least one radial diameter D of the sample tube (4) and is positioned at an axial distance to the z-axis radially innermost NMR coil of the NMR coil system (9; 9") which is smaller is the radial coil diameter of the innermost NMR coil.
[20]
20. NMR probe head according to claim 18 or 19, characterized in that at least one centering device (5; 5 '; 5 "; 5"; 5 ""; 5a; 6; 6'; 8) with an RF shielding tube of the NMR Sample head (3) RF-moderately electrically contacted.
[21]
21. NMR probe head according to one of claims 18 to 20, characterized in that at least one centering device (5; 5 '; 5 "; 5"; 5 ""; 5a; 6; 6'; 8) is shaped such that there is no path within the centering device (5; 5 '; 5 "; 5"'; 5 ""; 5a; 6; 6 '; 8) which encloses the sample tube (4) in its measuring position.
[22]
22. NMR probe head according to one of the preceding claims, characterized in that at least one of the axially above the NMR coil system (9; 9 ") arranged centering means (5; 5 '; 5"; 5 "'; 5a; 6; ') consists of a material which has an electrical conductivity <10 "8 S / m.
[23]
23. NMR probe head according to one of the preceding claims, characterized in that at least one of the axially above the NMR coil system (9; 9 ') arranged centering means (5; 5'; 5 "; 5" '; 5 ""; 5a ; 6; 6 ') consists of a material which has a magnetic susceptibility <1.0 ppm in terms of amount.
[24]
24. NMR probe head according to one of the preceding claims, characterized in that the sample tube (4) flowing around tempering at at least one of the centering means (5; 5 '; 5 "; 5"'; 5 ""; 5a; 6; 6 ' 8) does not flow between the centering means (5; 5 '; 5 "; 5"'; 5 ""; 5a; 6; 6 '; 8) and the sample tube (4) but radially away from the z-axis staggered exhaust holes is passed.
[25]
25. NMR measuring arrangement with an NMR probe head (3) according to one of the preceding claims, with an NMR magnet system, a shim system, a turbine and a device for transporting a sample tube (4) from outside the NMR magnetic system to the measuring position of the sample tube (4) in the NMR probe head (3).

类似技术:

公开号 | 公开日 | 专利标题

DE102013212312B4|2017-02-02|NMR probe head with improved centering of the sample tube

EP1124138B1|2007-06-06|Cooled NMR probe head with thermal isolation of the sample to be measured

DE102005047883B4|2008-11-20|Nuclear magnetic resonance measuring head comprising at least two coils / resonator arrangements with reduced coupling

EP1126284B1|2007-06-27|Cooled NMR sample head with uniform temperature equalization of the test sample

DE102013219453B3|2014-08-07|Dynamic nuclear polarization-device for producing hyperpolarized liquid for nuclear magnetic resonance- and magnetic resonance imaging-measurements, has cryostat which has opening and load path for loading cryostat with measuring sample

EP3264125B1|2020-09-16|Hf coil assembly for nmr

DE10006324C1|2001-08-16|Cooled NMR probe head with device for centering the measurement sample

DE102014201076B3|2015-03-05|Transport container for an NMR MAS rotor

DE3408346A1|1984-10-11|HIGH FREQUENCY PROBE FOR A GYROMAGNETIC RESONANCE SPECTROMETER

EP3407080B1|2021-06-30|Nmr sample head with releasable hf seal

EP1746432A1|2007-01-24|Rf shield with reduced coupling to the rf resonator system

EP1371996A2|2003-12-17|Device for positioning a long sample tube relative to an NMR receiving coil system

DE102013204952B3|2014-05-15|Active shielded cylindrical gradient coil system with passive RF shielding for NMR devices

DE102006046888B4|2010-12-16|Cooled magnetic resonance probe head with a vacuum container and associated NMR measuring apparatus

DE102007049701B4|2010-09-23|NMR probe with multiple resonator systems for simultaneous measurement of multiple samples in a coupled mode

EP1918731B1|2012-03-07|Sample container for NMR measurements with homogenisation of sample volume by sample container boundaries

DE102011006157B4|2016-06-16|Double tuned RF resonator

EP3182147A1|2017-06-21|Readily accessible deep cooled nmr shim assembly

EP3422035B1|2019-09-11|Nmr sample head with a multi-part insert lower part

EP1795910A1|2007-06-13|Reduction of eddy current losses in electrically conductive samples by means of special NMR sample tubes

DE102020202243A1|2021-08-26|Sample extension on the probe head side to reduce the B0 field interference at the end of the sample tube

EP3508868B1|2020-02-26|Nmr shim system

EP3315988B1|2019-03-06|Hf resonator arrangement

EP3889630A1|2021-10-06|Magnetic-compensated nmr rotor and method of design and manufacture

DE102007002440B4|2008-09-25|Susceptibility-compensated detector device for nuclear magnetic resonance measurements of small sample volumes

同族专利:

公开号 | 公开日

JP2015038471A|2015-02-26|

CN104251981B|2019-06-07|

CH708241A2|2014-12-31|

US9726735B2|2017-08-08|

GB2520375B|2020-06-17|

DE102013212312A1|2014-12-31|

US20150002152A1|2015-01-01|

JP6425429B2|2018-11-21|

DE102013212312B4|2017-02-02|

CN104251981A|2014-12-31|

GB2520375A|2015-05-20|

GB201411354D0|2014-08-13|

引用文献:

公开号 | 申请日 | 公开日 | 申请人 | 专利标题

GB1196820A|1967-11-25|1970-07-01|Jeol Ltd|Sample Holder for a Nuclear Magnetic Resonance Instrument.|

US4088944A|1976-10-04|1978-05-09|Varian Associates, Inc.|NMR Spectrometer employing self centering turbine|

JPS57168049U|1981-04-17|1982-10-22|

DE4018734C2|1990-06-12|1992-10-15|Spectrospin Ag, Faellanden, Zuerich, Ch|

US5408181A|1993-08-30|1995-04-18|Auburn International, Inc.|NMR system for measuring polymer properties|

DE19844895C2|1998-09-30|2000-10-05|Wilfried Hellmuth Bergmann|Probe head for an NMR spectrometer|

US6177798B1|1999-07-27|2001-01-23|Varian, Inc.|Flow-through NMR probe having a replaceable NMR flow tube|

US6396274B1|1999-11-05|2002-05-28|Varian, Inc.|Dual-function NMR probe|

DE10006324C1|2000-02-12|2001-08-16|Bruker Ag Faellanden|Cooled NMR probe head with device for centering the measurement sample|

JP4304856B2|2000-10-31|2009-07-29|株式会社島津製作所|Nuclear magnetic resonance apparatus|

DE10111674C2|2001-03-09|2003-02-06|Bruker Biospin Ag Faellanden|Device for transporting and accurately positioning a sample tube in a high-resolution NRM spectrometer|

DE10111672C2|2001-03-09|2003-02-06|Bruker Biospin Ag Faellanden|Device for precise centering of an NMR sample tube|

DE10130283C1|2001-06-26|2003-03-13|Bruker Biospin Gmbh|NMR sample holder and associated operating procedures|

DE10157972B4|2001-11-27|2004-01-08|Bruker Biospin Ag|NMR spectrometer and operating method with stabilization of the transverse magnetization in superconducting NMR resonators|

DE10225958B3|2002-06-12|2004-03-04|Bruker Biospin Ag|Apparatus for positioning an elongate sample tube filled with a measurement substance relative to a NMR receiver coil system|

WO2005078468A2|2004-01-20|2005-08-25|The University Of Houston System|Superconducting loop, saddle and birdcage mri coils comprising built-in capacitors|

GB0411072D0|2004-05-18|2004-06-23|Oxford Instr Superconductivity|Apparatus and method for performing in-vitro dnp-nmr measurements|

JP4647984B2|2004-12-02|2011-03-09|株式会社日立製作所|Nuclear magnetic resonance probe coil|

JP4673196B2|2005-11-24|2011-04-20|株式会社日立製作所|NMR equipment|

JP2007315886A|2006-05-25|2007-12-06|Hitachi Ltd|Gas bearing for nuclear magnetic resonance apparatus, and the nuclear magnetic resonance apparatus|

JP4851261B2|2006-08-17|2012-01-11|株式会社神戸製鋼所|Cooled NMR probe head|

US20080179275A1|2007-01-27|2008-07-31|Kurt Himmelsbach|Cap for an NMR sample tube with inner sealing lip|

JP2008209291A|2007-02-27|2008-09-11|Hitachi Ltd|Nmr device|

DE102008033886B4|2008-07-18|2012-03-08|Bruker Biospin Ag|Apparatus for carrying out DNP-NMR measurements with compensation arrangement|

DE102010029080B4|2010-05-18|2013-05-08|Bruker Biospin Ag|Tempering device for an NMR sample tube and method for controlling the temperature of an NMR sample tube|

CN101907586B|2010-06-11|2012-03-07|中国石油天然气股份有限公司|High-temperature high-pressure clamp for testing rock core by nuclear magnetic resonance|

US8704520B2|2010-12-08|2014-04-22|General Electric Company|Radio frequency coil and apparatus|

US9063060B2|2011-10-10|2015-06-23|Jeol Resonance Inc.|Solid-state NMR spectrometer, sample holder therefor, and method of solid-state NMR spectroscopy|

GB2506851B|2012-09-28|2014-11-12|Schlumberger Holdings|NMR sample containment|

US9366736B2|2012-12-13|2016-06-14|Battelle Memorial Institute|Sealed magic angle spinning nuclear magnetic resonance probe and process for spectroscopy of hazardous samples|

DE102013204131B3|2013-03-11|2014-02-06|Bruker Biospin Ag|Nuclear magnetic resonance probe head has sliding bush that exerts decelerating friction at piston actuating rod for linear displacement of capacitor piston while steep flanks in sawtooth shape via piston actuating rod|

GB2515524A|2013-06-26|2014-12-31|John Beausire Wyatt Webber|Nuclear magnetic resonance probes|

US10281416B2|2014-08-04|2019-05-07|Waters Technologies Corporation|Devices for use in solid-state NMR analysis|JP6321978B2|2014-01-27|2018-05-09|富士フイルム株式会社|Organic thin film transistor, organic semiconductor thin film and organic semiconductor material|

KR101676336B1|2015-05-14|2016-11-15|한국기초과학지원연구원|Probe unit for nuclear magnetic resonance|

DE102016218772A1|2016-09-28|2018-03-29|Bruker Biospin Gmbh|Improved tempering of an NMR MAS rotor|

US10634743B2|2016-10-10|2020-04-28|Arizona Board Of Regents On Behalf Of The University Of Arizona|Sample tube insertion guide device|

DE102017204922A1|2017-03-23|2018-09-27|Siemens Aktiengesellschaft|Device for connecting shielding tubes of a high-voltage device|

DE102017208841B3|2017-05-24|2018-10-04|Bruker Biospin Ag|NMR probe head with detachable HF seal|

DE102017211016B3|2017-06-29|2018-10-11|Bruker Biospin Ag|NMR probe head with multipart insert base|

DE102017215763B3|2017-09-07|2018-12-06|Bruker Biospin Ag|Fastening device for a NMR probe head with quick release|

DE102018202890A1|2018-02-26|2019-08-29|Bruker Biospin Gmbh|NMR probe head with carrying partin the shielding tube|

DE102018205535B3|2018-04-12|2019-07-04|Bruker Biospin Ag|Transport device for tempered NMR test samples with double tube system|

EP3715893B1|2019-03-25|2021-02-24|Bruker Switzerland AG|Nmr spectrometer with quick swap system for samples|

JP2021139774A|2020-03-05|2021-09-16|日本電子株式会社|Nmr measurement system and method for centering sample tube|

法律状态:
2019-10-31| PFA| Name/firm changed|Owner name: BRUKER SWITZERLAND AG, CH Free format text: FORMER OWNER: BRUKER BIOSPIN AG, CH |

优先权:

申请号 | 申请日 | 专利标题

DE102013212312.4A|DE102013212312B4|2013-06-26|2013-06-26|NMR probe head with improved centering of the sample tube|

[返回顶部]