RU2818882C1 - Large internal volume thermostat for a magnet of an nmr spectrometer - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: use for temperature control of samples in magnets of NMR spectrometers. Essence of the invention is that a large internal volume thermostat for a magnet of an NMR spectrometer comprises a heat exchanger, which is a line of tubes through which a heat carrier flows, wherein the heat exchanger tubes are soldered to the copper pipe passing along the entire thermostat, the thermostat is closed by an external protective casing with diameter of 40 mm, a heat insulation layer is used between the copper pipe and the protective casing, copper is used as material for heat exchanger tubes, in addition, the thermostat contains a container for placing test tubes with samples before the beginning of the thermostating process, which is attached to the fixing cover through a rubber ring pressed to the fixing cover by a plate, wherein the compressed rubber ring has an outer diameter greater than the diameter of the inner hole of the container.

EFFECT: providing the possibility of creating a thermostat for a magnet of an NMR spectrometer with high temperature uniformity inside it, as well as with the possibility of using on a wide class of commercial NMR magnets, without using additional modifications of NMR magnets.

1 cl, 1 dwg

Description

The invention is intended for temperature control of samples in the magnets of NMR spectrometers, which are characterized by significantly limited free space in the internal hole. The invention can be used in the field of synthesis and crystallization of chemical compounds to maintain the temperature of samples located in a magnetic field in the range from -30 to +100°C.

A device for thermostatting biological samples is known (RF patent No. 2134416 dated 08/09/1996, G01N 24/08, F25B 29/00, F25B 21/02). The thermostating device contains a thermoblock, in thermal contact with the walls of which the cold junctions of the thermopile are located on both sides, the main and additional water heat exchangers for cooling the hot junctions of the thermopile, connected in series, a heat exchanger for the coolant, which is in thermal contact with one of the water heat exchangers, a thermostatting jacket with the sample under study, a unit for setting and maintaining a given temperature, connected to the heater. Coolant is pumped through a sealed closed system using a pump and a flow switch.

The disadvantage of this solution is the use of a thermostatic jacket of the NMR relaxometer-diffusometer sensor, which differ in design, size, and internal volume depending on the sensor manufacturer and spectrometer model, which makes the device not universal. In addition, the use of an NMR relaxometer-diffusometer sensor implies the possibility of thermostatting only in a small region of space of the NMR magnet (in the region of a uniform field). The inability to effectively use the space of an NMR magnet significantly limits the possible use of this device.

The objective of the invention, which the claimed invention is aimed at, is to create a thermostat for the magnet of an NMR spectrometer with high uniformity of temperature inside it, as well as the possibility of application on a wide class of commercial NMR magnets, without using additional modifications of the NMR magnets.

The problem is solved by the fact that in a thermostat of large internal volume for the magnet of an NMR spectrometer, containing a heat exchanger, which is a line of tubes through which the coolant flows, according to the invention , the heat exchanger tubes are soldered to a copper pipe running along the entire thermostat, the thermostat is closed with an external protective casing with a diameter of 40 mm, a layer of thermal insulation is used between the copper pipe and the protective casing, copper is used as the material for the heat exchanger tubes. In addition, the thermostat contains a container for placing test tubes with samples before starting the thermostating process. This container is attached to the retaining lid through a rubber ring pressed against the retaining lid by a plate, while the compressed rubber ring has an outer diameter larger than the diameter of the internal hole of the container, which ensures reliable fastening.

Temperature inhomogeneity inside the thermostat, caused by its large length, is minimized by using an extended line of copper tubes through which the coolant flows. They are soldered to a copper pipe running along the entire thermostat, which, due to its high thermal conductivity and thermal insulation from the rest of the thermostat, increases the temperature uniformity in it.

In fig. 1 shows a diagram of the device, where:

1 - thermostat inlet;

2 - heat exchanger tubes;

3 - jumpers;

4 - thermostat outlet;

5 - copper pipe;

6 - container for placing test tubes with samples;

7 - locking cover;

8 - rubber ring;

9 - plate;

10, 11 - parts forming the magnet flange;

12 - walls of the internal hole of the magnet;

13 - external protective casing;

14, 15 - metal flanges.

The device works as follows.

Coolant is supplied to the inlet (1) of the thermostat. It passes through four tubes (2), connected together through jumpers (3) soldered to them, and then exits through the hole (4). The tubes (2) are soldered to the pipe (5), which ensures thermal contact between the parts. Copper is used as the material for parts (2, 3, 5), which is an important characteristic of the thermostat, since it allows you to obtain a uniform temperature inside the thermostat and a high rate of change, and also simplifies the process of joining parts by soldering.

Before starting the thermostating process, test tubes with samples are placed in a container (6), which is attached to a locking lid (7). The locking lid closes the container (6) and secures it in the thermostat. The key feature of the container (6) is the ability to place several tubes in it, effectively using the entire space of the internal opening of the magnet. The container (6) is secured to the retaining lid (7) through a rubber ring (8) pressed against the retaining lid (7) by a plate (9). The compressed rubber ring has an outer diameter slightly larger than the diameter of the inner hole of the container (6). As a result, friction between the rubber ring and the container guarantees the stability of the connection, and the absence of screw fastenings simplifies the installation of tubes in the thermostat. After the end of the experiment, the container is detached from the locking lid (7), and the test tubes can be removed through the lower hole of the container (6).

Parts (10) and (11), connected together, form a magnet flange, designed to securely attach the thermostat to the magnet and place the container with test tubes (6) in the thermostat. The walls of the internal hole of the magnet are marked with the number 12. Part (11) ensures that pipes (2) are led outside the thermostat, which greatly simplifies connecting the thermostat to the coolant supply system.

The thermostat is closed by an outer casing (13). The casing (13) and copper pipe (5) are attached to the part (10) through metal flanges (14 and 15), which are soldered to the casing (13) and to the pipe (5), respectively. To ensure tightness and prevent the mixing of air from different thermal circuits, metal flanges are connected to the part (10) through seals. In addition, a layer of thermal insulation is used between the copper pipe (5) and the protective casing (13). Thus, the interior of the thermostat is thermally insulated from its protective casing, which helps to achieve significant heating or cooling of the test tubes with high temperature uniformity inside the thermostat.

Features of the invention.

• The coolant flows through copper tubes located along the entire thermostat, which significantly increases the uniformity of temperature inside it.

• The diameter of the protective casing is 40 mm, which allows you to work on a wide class of commercial NMR magnets without using additional modifications of the NMR magnets.

• The holes for the screw connection of the part (10) with the NMR magnet coincides with the position of the holes in the sensors of Bruker NMR spectrometers.

• Several test tubes can be placed in a thermostat, which allows simultaneous experiments to be carried out in magnetic fields of different strengths.

• Fastening the container (6) through a rubber ring makes it easy to place the tubes in the thermostat.

Private sale of the device by the authors of the invention.

• The container (6) is made of aluminum and has an internal diameter of 16 mm and an external diameter of 19 mm.

• Parts (10) and (11) are made of caprolon and connected together with M3 screws, forming a flange with a diameter of 80 mm and a height of 64 mm.

• The protective casing (13) is made of aluminum and has an internal and external diameter of 37 and 40 mm respectively.

• The pipe (5) has an internal diameter of 20 and an external diameter of 22 mm.

• Copper tubes (2) have internal and external diameters of 5.15 and 6.35 mm, respectively.

• The jumpers (3) have internal and external diameters of 3.15 and 4.75 mm.

• The flange (14) has an outer diameter of 69 mm. The diameter of the hole for attaching the casing (13) is 40.2 mm.

• The flange (15) has an outer diameter of 41 mm. The diameter of the hole for the pipe (5) is 22.2 mm.

• Part (7) together with the test tubes is attached to part (10) via an M22 threaded connection 14 mm long.

• The flanges (14, 15) are attached to the part (10) with six M3 screws each.

Technical characteristics of the invention.

• The operating temperature range of the thermostat is from -30°C to +100°C.

• Temperature uniformity in the thermostat is 0.2°C.

• The coolant passes through 4 heat pipes

• The inlet and outlet openings for the coolant are located on one side of the thermostat.

Claims (1)

A thermostat with a large internal volume for the magnet of an NMR spectrometer, containing a heat exchanger, which is a line of tubes through which coolant flows, characterized in that the heat exchanger tubes are soldered to a copper pipe running along the entire thermostat, the thermostat is closed by an external protective casing with a diameter of 40 mm, between the copper pipe and the protective casing uses a layer of thermal insulation, copper is used as a material for the heat exchanger tubes, in addition, the thermostat contains a container for placing test tubes with samples before starting the thermostating process, which is attached to the retaining lid through a rubber ring pressed to the retaining lid with a plate, when In this case, the compressed rubber ring has an outer diameter larger than the diameter of the inner hole of the container.