NMR measurement system

Abstract

This prevents the sample tube from shifting its mounting position on the rotor due to the impact when it reaches and settles on the detector. [Solution] The NMR measurement system includes a sample tube 20, a strip-shaped sample tube lock 40 positioned at a predetermined location on the outer circumference of the sample tube 20 and protruding outward, a holder 30 that supports the lower end of the sample tube lock 40 around the upper end of the insertion space when the sample tube 20 is inserted through its center, a rotor 32 that surrounds the sample tube lock 40 and the sample tube 20 through an internal void and includes a groove 32d formed on its inner circumferential surface so as to be recessed outward near the holder 30, and a holder lock 50 having a cylindrical side wall, a top wall extending inward from the upper end of the side wall and having an insertion hole formed in the center through which the sample tube 20 is inserted, and a flange portion that spreads outward from the outer circumference of the lower end of the side wall, the outer circumference of the flange portion being housed in the groove and fixed to the rotor.

Description

Technical Field

[0001] The present disclosure relates to an NMR (nuclear magnetic resonance) measurement system, particularly to a holding structure for a sample tube that houses a sample to be measured.

Background Art

[0002] In an NMR measurement system, measurement is performed with a solution sample to be measured enclosed in an elongated sample tube.

[0003] Normally, the sample tube can be rotated during measurement, and the sample tube is housed in a cylindrical rotor. The sample tube extends downward from the rotor, and NMR measurement is performed on the sample housed in the downward-extended part by a detector arranged around it. The detector has a specific signal detection region, and in order to obtain optimal sensitivity, it is necessary to align the position so that the sample is present in that detection region.

[0004] Therefore, first, the region of the sample enclosed in the sample tube is precisely aligned using a separately prepared gauge. The loading of the rotor with the sample tube attached to the detector is performed based on the principle of an air floater using flowing air.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] As mentioned above, the rotor is loaded onto the detector using the principle of an air floater, so the impact when the rotor reaches and sits on the detector is relatively small. However, residual impact may cause the sample tube's mounting position on the rotor to shift. If such a shift occurs, the sample position will differ from the intended position, which may interfere with NMR measurements. [Means for solving the problem]

[0007] The NMR measurement system according to this disclosure is an NMR measurement system comprising: a cylindrical sample tube containing a sample inside; a strip-shaped sample tube lock positioned at a predetermined location on the outer circumference of the sample tube and protruding outward; a holder having a vertical insertion space formed in the center through which the sample tube is inserted, and supporting the lower end of the sample tube lock around the upper end of the insertion space when the sample tube is inserted; a rotor extending upward from the top of the holder, surrounding the sample tube lock and the periphery of the sample tube via an internal void, and including a groove formed on the inner circumferential surface near the holder so as to be recessed outward; a holder lock having a cylindrical side wall, a top wall extending inward from the upper end of the side wall and having an insertion hole formed in the center through which the sample tube is inserted; and a flange portion spreading outward from the outer circumference of the lower end of the side wall, the outer circumference of the flange portion being housed in the groove and fixed to the rotor.

[0008] The outer circumference of the side wall of the holder lock has an outer diameter that decreases towards the top, and its inner diameter is larger than the outer diameter of the upper part of the holder lock and smaller than the outer diameter of the lower part. By inserting a pipe-shaped jig into the internal gap around the side wall of the holder lock, the flange portion can be moved inward from the groove.

[0009] The holder and the rotor are made of separate components, the rotor includes a holder housing hole through which the holder is inserted, the upper end of the holder has a holder flange portion that widens outward, the lower surface of the holder flange portion is supported by the upper surface of the rotor around the holder housing hole, and the holder is preferably movable upward from the holder housing hole of the rotor.

[0010] The holder lock may have a plurality of notches extending vertically formed in its side wall and flange portion. [Effects of the Invention]

[0011] According to the NMR measurement system of this disclosure, it is possible to prevent the mounting position of the sample tube on the rotor from shifting due to the impact when the rotor reaches and sits on the detector. [Brief explanation of the drawing]

[0012] [Figure 1] This is a cross-sectional view showing the main components of the detector in the NMR measurement system related to this disclosure. [Figure 2] This is a cross-sectional view showing the configuration of the parts of the rotor and holder that hold the sample tube. [Figure 3] This is a perspective view of the HolderLock 50. [Figure 4] Figure 4 illustrates the process of replacing the sample tube, where (A) is a perspective view showing the configuration of the jig 70, (B) shows the jig 70 partially inserted, and (C) shows the jig 70 fully inserted. [Modes for carrying out the invention]

[0013] The embodiments of this disclosure will be described below with reference to the drawings. The embodiments described below are not limiting to this disclosure, and configurations formed by selectively combining multiple examples are also included in this disclosure.

[0014] "System Configuration" Figure 1 is a cross-sectional view showing the main components of the detector 100 of the NMR measurement system according to this disclosure. The housing 10 is hollow cylindrical, and a similarly hollow cylindrical detection unit 18 is connected to its lower side. The housing 10 and the detection unit 18 may be integrated. The housing 10 has a larger diameter than the detection unit 18 and has a cylindrical space 12 inside. A relatively small diameter projection 18c is provided at the upper end of the detection unit 18. The lower end of the housing 10 is connected to the annular region around the projection 18c of the detection unit 18, surrounding it. The inside of the projection 18c is a cylindrical housing space 14. In addition, the housing 10 and the detection unit 18 have a plurality of passages 16 for the circulation of air.

[0015] The sample tube 20 is a long, cylindrical pipe in which the sample 22 is contained in a predetermined portion (the lower end in this example). After the sample 22 is contained in the sample tube 20, it is sealed to enclose the sample 22. The upper part of the sample tube 20 is fixed to the holder 30 and the rotor 32. The rotor 32 and the holder 30 are cylindrical. In this example, the rotor 32 and the holder 30 are made of separate components, with the holder 30 fixed to the lower part of the rotor 32, but the rotor 32 and the holder 30 may be a single unit. The rotor 32 has a larger diameter than the holder 30, and the lower surface of the rotor 32 widens in an annular shape around the upper end of the holder 30. The holder 30 and the rotor 32 can be made of fluororesin or the like.

[0016] The rotor 32 is housed in the cylindrical space 12, and the holder 30 is housed in the housing space 14. The annular lower surface of the rotor 32, located around the holder 30, is supported by the annular upper end of the projection 18c.

[0017] The sample tube 20 extends further downward from the lower end of the holder 30. A cylindrical space 24 with a closed upper end is provided in the center of the detection unit 18. A hole is formed in the center of the upper wall of this space 24, and the sample tube 20 is inserted through it.

[0018] In the configuration space 24, a temperature-adjusting gas is circulated so that the temperature around the sample tube 20 can be adjusted to an appropriate value. Note that illustration of the flow path of this temperature-adjusting gas and the like is omitted.

[0019] Around the position of the sample 22 in the sample tube 20 of the detection unit 18, a detection unit 34 for detecting an NMR signal is arranged. This detection unit 34 includes a detection coil for transmitting and receiving RF signals. Further, around the housing 10, a static magnetic field generation unit including a superconducting coil and the like is provided.

[0020] With the sample tube 20 fixed to the holder 30 and the rotor 32, the sample tube 20 is inserted through the hole in the upper wall of the detection unit 18. Then, the rotor 32 and the holder 30 to which the sample tube 20 is attached are moved using the principle of an air floater and lowered to the position shown in the figure.

[0021] Here, in this example, by blowing air onto the rotor 32 using the passage 16, the rotor 32 can be rotated. Therefore, NMR measurement can be performed while rotating the sample tube 20. Note that the passage 16 can also be used for transporting the sample tube 20 by an air floater.

[0022] As shown in FIG. 1, with the rotor 32 supported by the housing 10, the sample 22 is positioned at an appropriate position with respect to the detection unit 34. Then, in a state where a predetermined static magnetic field is formed by the static magnetic field generation unit arranged around the housing 10, by transmitting and receiving RF by the detection unit 34, an NMR signal for the sample 22 can be detected. Further, by blowing out air from the passage 16 and rotating the rotor 32, an NMR signal can be detected while rotating the sample 22.

[0023] "Configuration of Rotor and Holder" FIG. 2 is a cross-sectional view showing the configuration of the portion of the rotor 32 and the holder 30 that holds the sample tube 20.

[0024] The base 30a of the holder 30 is cylindrical, and a holder flange portion 30c that widens outward is formed at its upper end. A cylindrical insertion space 30b for inserting the sample tube 20 is provided in the center of the holder 30, extending vertically through it. An annular groove that widens outward from the insertion space 30b is provided in the middle of the insertion space 30b in the vertical direction, and an O-ring 36 is housed there. This O-ring 36 separates the vertical space of the insertion space 30b.

[0025] The rotor 32 is a hollow cylindrical shape overall, with an internal void 32a formed on the inside of its upper part. The inner surface of the rotor 32 has a step 32c in the middle section, and the inner diameter decreases from the middle section downwards. The step 32c is an annular plane that forms the bottom surface of the internal void 32a. A cylindrical holder housing hole 32b is formed at the bottom of the rotor 32 (below the step 32c) and extends downwards in a manner continuous with the internal void 32a. In the middle section of the holder housing hole 32b in the vertical direction, two annular grooves are provided, extending outward from the holder housing hole 32b, separated vertically, and O-rings 38 are housed in each of these grooves. These O-rings 38 separate the vertical space of the holder housing hole 32b.

[0026] The holder 30 is housed in the holder housing hole 32b within the rotor 32. The lower surface of the holder flange portion 30c is supported by the step 32c around the holder housing hole 32b. As mentioned above, the rotor 32 and the holder 30 may be constructed as a single unit.

[0027] Furthermore, a sample tube lock 40 is attached to a predetermined position on the sample tube 20. The sample tube lock 40 is cylindrical or strip-shaped and is provided so as to surround the outer circumference of the sample tube 20. The vertical position is determined by considering the vertical length of the sample tube lock 40, so that the vertical position of the sample 22 inside the sample tube 20 is within the measurement area of ​​the detection unit 34 (see Figure 1).

[0028] The sample tube lock 40 should be made of a material and have dimensions that allow for a light press-fit onto the sample tube 20. Specifically, the inner diameter of the sample tube lock 40 should be slightly smaller than the outer diameter of the sample tube 20, and it should be attached to the outer circumference of the sample tube 20 in an expanded state due to its elasticity. Alternatively, the sample tube lock 40 may be constructed by wrapping adhesive tape around it to achieve a constant outer diameter.

[0029] The sample tube lock 40 protrudes outward from the periphery of the sample tube 20. The outer diameter of the sample tube lock 40 should be smaller than the inner diameter of the holder lock 50, which will be described later.

[0030] The sample tube 20, to which the sample tube lock 40 is attached, is inserted into the insertion space 30b from top to bottom. Since the sample tube lock 40 protrudes outward from the sample tube 20, the lower end surface of the sample tube lock 40 is supported by the step 32c of the rotor 32. As a result, the vertical position of the sample 22 inside the sample tube 20 is positioned within the measurement area for detection by the detection unit 34.

[0031] In this manner, once the sample tube 20 is attached to the holder 30, the holder lock 50 is then inserted into the internal gap 32a of the rotor 32 from top to bottom.

[0032] "Holderlock configuration" Figure 3 is a perspective view of the holder lock 50. The holder lock 50 is hat-shaped with an open bottom. A top wall 52 is positioned at the upper end of the cylindrical side wall 56. An insertion hole 54 is formed in the center of the top wall 52, through which the sample tube 20 is inserted.

[0033] The cylindrical side wall 56 includes an upper section 56a, a middle section 56b, and a lower section 56c. The upper section 56a is relatively thin-walled, the lower section 56c is relatively thick-walled, and the middle section 56b gradually increases in thickness from the upper section 56a to the lower section 56c towards the bottom. Alternatively, the thickness may be constant and the diameter may widen towards the bottom. In the illustrated example, only the middle section is sloped, but the diameter may gradually widen towards the bottom overall.

[0034] An annular flange portion 58 is formed at the lower end of the side wall 56, projecting outward from its outer circumference.

[0035] Multiple vertically extending notches 60 are formed on the periphery of the top wall 52, the side wall 56, and the flange portion 58, spaced apart in the circumferential direction. In this example, five notches 60 are provided at equal intervals in the circumferential direction. This makes it easier for the flange portion 58 to deform in a direction that reduces its outer diameter when a force is applied to it from the outside inward. When the force is removed, it protrudes outward and returns to its original position.

[0036] Figure 2 shows the holder lock 50 after it has been mounted on the rotor 32. Near the step 32c of the rotor 32, that is, slightly above it, an annular groove 32d is formed on the inner circumferential surface that is recessed outwards. The lower end of this groove 32d is located at the upper end of the holder 30, and the width (distance in the vertical direction) of the groove 32d is set to correspond to the thickness of the flange portion 58. The vertical distance of the groove 32d may be slightly larger than the thickness of the flange portion 58. The vertical distance of the groove 32d may be uniform in the depth direction, but making the entrance side larger makes it easier for the flange portion 58 to fit.

[0037] Furthermore, the depth of the groove 32d facing outward should be greater than or equal to the outer diameter of the flange 58 when it is wide, so that no inward force is applied to the flange 58.

[0038] "Setting the sample tube into the housing" When performing an NMR measurement, first, the sample 22 is placed in the sample tube 20. As described above, the sample 22 is in liquid form, and a predetermined amount is introduced into the sample tube 20.

[0039] Next, the sample tube lock 40 is set on the sample tube 20. For example, the sample tube lock 40 is fitted onto the outer circumference of the sample tube 20 by applying force, and set to a predetermined vertical position.

[0040] The sample tube 20 is inserted into the insertion space 30b at the center of the holder 30 set on the rotor 32, and the lower end of the sample tube lock 40 is supported by the top surface of the holder 30 around the upper end of the insertion space 30b.

[0041] In this state, the sample tube 20 is inserted through the insertion hole 54 of the holder lock 50 and the holder lock 50 is moved downward. The holder lock 50 descends to the position of the sample tube lock 40, and the holder lock 50 houses the sample tube lock 40 inside.

[0042] The outer diameter of the flange portion 58 of the holder lock 50 is larger than the inner diameter of the internal gap portion 32a of the rotor 32, so it should be slightly contracted during insertion. It is best to push the top wall 52 of the holder lock 50 downwards to move it.

[0043] As described above, the rotor 32 is provided with a groove 32d into which the flange portion 58 at the bottom of the holder lock 50 fits. When the bottom surface of the holder lock 50 reaches the surface of the upper end of the holder 30 and insertion is complete, the contractile force applied to the flange portion 58 is simultaneously released, the flange portion 58 enters the groove 32d, and the holder lock 50 is coupled to the rotor 32.

[0044] In this example, the holder 30 is also pressed down by the bottom surface of the holder lock 50 and fixed to the rotor 32. The holder flange portion 30c is pressed down by the holder lock 50 against the step 32c of the rotor 32 located below it.

[0045] "Replacing the sample tube" When replacing the sample tube 20, a dedicated jig 70 can be used. Figure 4(A) is a perspective view showing the configuration of the jig 70, Figure 4(B) shows the jig 70 inserted up to the holder lock, and Figure 4(C) shows the holder lock 50 inserted all the way down.

[0046] The jig 70 is cylindrical, and its outer diameter is approximately the same as the inner diameter of the rotor 32. The inner diameter of the jig 70 is approximately the same as or slightly larger than the outer diameter of the upper part of the holder lock 50, and smaller than the outer diameter of the lower part. Therefore, by pressing the jig 70 downward, the holder lock 50 is pressed inward. The holder lock 50 is provided with a notch 60, and the outer circumference of the lower part 56c of the holder lock 50 moves inward, as well as towards the notch 60 and upward. As a result, the flange portion 58 of the holder lock 50 moves inward.

[0047] In this way, by inserting the jig 70, the flange portion 58 of the holder lock 50 is detached from the groove portion 32d of the rotor 32, and the lock between the holder lock 50 and the rotor 32 can be released. Therefore, the jig 70 and the sample tube 20 can be pulled upward, and the sample tube 20 can be removed from the rotor 32. The jig 70 can be made of a resin such as polyacetal.

[0048] Furthermore, the sample tube 20 can be more easily lifted by pushing up the holder 30 from below. [Explanation of symbols]

[0049] 10 Housing, 12 Cylindrical space, 14 Storage space, 16 Passage, 18 Detection unit, 20 Sample tube, 22 Sample, 24 Placement space, 30 Holder, 32 Rotor, 32d Groove, 34 Detection unit, 36, 38 O-rings, 40 Sample tube lock, 50 Holder lock, 52 Top wall, 54 Insertion hole, 56 Side wall, 58 Flange, 60 Notch, 70 Fixture, 100 NMR measurement system.

Claims

1. An NMR measurement system, A cylindrical sample tube containing a sample inside, A strip-shaped sample tube lock is positioned at a predetermined location on the outer circumference of the sample tube and protrudes outward, A vertical insertion space is formed in the center through which the sample tube is inserted, and a holder supports the lower end of the sample tube lock around the upper end of the insertion space when the sample tube is inserted. A rotor extending upward from the top of the holder, surrounding the sample tube lock and the periphery of the sample tube via an internal void, and including a groove formed on the inner circumferential surface near the holder so as to be recessed outward, A holder lock having a cylindrical side wall, a top wall positioned at the upper end of the side wall with a through hole formed in its center through which the sample tube is inserted, and a flange portion that extends outward from the outer circumference of the lower end of the side wall, wherein the outer circumference of the flange portion is housed in the groove and fixed to the rotor, including, NMR measurement system.

2. An NMR measurement system according to claim 1, The outer circumference of the side wall of the holder lock has an outer diameter that decreases towards the top. By inserting a pipe-shaped jig, whose inner diameter is larger than the outer diameter of the upper part of the holder lock and smaller than the outer diameter of the lower part, into the internal gap around the side wall of the holder lock, the flange portion can be moved inward from the groove. NMR measurement system.

3. An NMR measurement system according to claim 1, The holder and the rotor are made of separate components, the rotor includes a holder housing hole through which the holder is inserted, the upper end of the holder has a holder flange portion that widens outward, the lower surface of the holder flange portion is supported by the upper surface of the rotor around the holder housing hole, and the holder is movable upward from the holder housing hole of the rotor. NMR measurement system.

4. An NMR measurement system according to any one of claims 1 to 3, The holder lock has a plurality of notches extending vertically formed in the side wall and the flange portion. NMR measurement system.

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