JPH0312576A - Electron spin resonance device - Google Patents

Abstract

PURPOSE:To fix a coil without using a bobbin by fixing a high frequency coil by shrinkage force of a thermal contractive tube. CONSTITUTION:After winding a coil 3 around the outside periphery of a jig 5, sleeves 6a, 6b of a conductive and non-magnetic material are fitted to both sides of the jig 5, welded and fixed, and the outside periphery of the coil 3 and the sleeves 6a, 6b is covered with a thermal contractive tube 4 and heated and contracted. In this state, even if the jig 5 is removed, the coil 3 is fixed in a state that desired length is held. This coil 3 is inserted into a cavity resonator 1 from insertion holes 7a, 7b, and thereafter, supported by supporting bodies 9a, 9b through a screw 8, and a sample tube 11 containing a sample 10 is inserted into the inside of the coil 3. In this case, the coil 3 is rotated and set to a position in which a Q value of the resonator 1 becomes the highest. In such a way, since the diameter of the coil 3 can be made small, the hole diameter of the resonator 1 can be made small and the Q value is enhanced. Also, by enlarging the diameter of the sample tube 11 by a portion of a bobbin, a large sample 10 can be contained, therefore, the sensitivity is improved, and also, the sample can be generated easily.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to holding a high-frequency coil incorporated in a cavity resonator of an electron spin resonance device (hereinafter referred to as an ESR device).

[Prior art] In an ESR device, in order to easily analyze ultrafine structures, an enthol (END) system is used to obtain an ESR signal while simultaneously performing both electron spin resonance and nuclear magnetic resonance.
OR) all conventions are used.

To implement this ENDO II method, it is necessary to incorporate a high frequency coil into the cavity resonator. On the other hand, in ESR measurement, the sensitivity is proportional to the Q value of the cavity resonator (hereinafter simply referred to as Q value), so it is desirable to keep the Q value high. E N D
The same applies to the ORall definition. Here, the Q value decreases rapidly as the diameter of the hole drilled in the cavity resonator for inserting the coil increases, and also decreases when the high frequency coil crosses the microwave electric field. Therefore, the dimensions of the coil are required to be as close as possible to the diameter of the sample tube.

By the way, the commonly used method for inserting a high-frequency coil into a cavity resonator is to wind the high-frequency coil to a desired length around the outer circumference of a glass bobbin, and then fix the coil to the bobbin with adhesive. There is.

[Problem to be solved by the invention] In this method of fixing the high frequency coil to the bobbin,
Since a glass bobbin having a relatively large diameter is inserted into the cavity resonator, the diameter of the hole drilled in the cavity resonator becomes large, and the Q value decreases for the reason described above. Furthermore, it is not possible to accommodate a sample as large as the thickness of the bobbin.

Therefore, the present invention has been made in view of this point, and it is an object of the present invention to fix a high frequency coil without using a bobbin.

[Problems to be Solved by the Invention] In order to achieve the above object, the electron spin resonance device of the present invention incorporates a high-frequency coil into the cavity resonator to achieve E
In an electron spin resonance apparatus that enables the N D ORall + standard method, a heat-shrinkable tube is placed around the outer circumference of the high-frequency coil, the heat-shrinkable tube is shrunk to fix the high-frequency coil, and the high-frequency coil is placed inside the high-frequency coil. This is characterized in that there is no need for a bobbin to be attached.

Hereinafter, embodiments of the present invention will be explained in detail based on the drawings.

[Example] Figure 1 is an enlarged cross-sectional view of essential parts showing an example of an ESR device according to the present invention, Figure 2 is a cross-sectional view illustrating a method of fixing a high-frequency coil used in the present invention, and Figure 3 is AA in Figure 2
FIG.

In Fig. 1, reference numeral 1 denotes a cavity resonator of the ESR device, which is placed in a uniform static magnetic field in a direction perpendicular to the plane of the paper. is supplied. Reference numeral 3 denotes a high-frequency coil for the entor device, and the contraction force of the heat-shrinkable tube 4 is utilized in manufacturing this coil.

Hereinafter, an example of a method for manufacturing a coil will be explained in detail based on FIGS. 2 and 3.

First, a rod-shaped jig 5 having the same outer diameter as the desired inner diameter of the coil is prepared. These jigs are marked 5a and 5 in Fig. 3.
It can be broken down into three parts as shown in b and 5c. Next, after winding the coil 3 to the desired number of turns and length around the outer circumference of the jig assembled into a rod shape, conductive and non-magnetic sleeves 6a and 6b are fitted from both sides of the jig 5. Then, each sleeve is fixed to both ends of the coil by welding. In this state, the heat-shrinkable tube 4 is placed over the outer periphery of the coil 3 and each of the sleeves 6a, 6b, and then heated and shrunk. Due to the contraction force of the contraction tube, the force of the coil 3 to expand outward is suppressed, and the coil 3 is fixed while maintaining a desired length. Therefore, even if the center part 5C of the jig 5 is pulled out by any means in this state and this jig is disassembled, the coil 3 will not be attached to the rod-shaped jig 5 as shown in FIG.
It remains in the same condition as when it was wound on. The heat-shrinkable tube 4 is made of a material that does not reduce the Q value, such as Teflon, and is made as thin as possible to suppress the Q value from decreasing.

After inserting the coil 3 formed in this manner into the cavity resonator 1 through insertion holes 7a and 7b provided in the upper and lower walls of the cavity resonator 1 shown in FIG. Support 9b. Further, a sample tube 11 containing a sample 10 is inserted into the coil 3 . This sample tube is in holder 12
It is removably attached to a sample stage 13 fixed on the cavity resonator 1 via a. 14a and 14b are connectors for connecting both ends of the coil 3 to a high frequency power source (not shown) via lead wires 15a and 15b.

Here, by making each sleeve 9a, 9b as long as possible, microwaves leaking from the insertion holes 7a, 7b can be suppressed. On the other hand, when the coil 3 is fixed in the cavity resonator 1, the Q value changes depending on its position in the circumferential direction, so it is necessary to rotate the coil and set it at the position where the Q value is the highest. In addition, lead wires 15a and 15b
If it is made longer than necessary, the amount of microwaves leaking through the lead wire will increase, causing problems such as a decrease in the Q value. Therefore, by connecting the lead wire at the shortest distance between the circumference of the outer circumference of the open end of the sleeve and the connector, it is possible to minimize the decrease in the Q value due to the length of the lead wire.

[Effects] As detailed above, according to the present invention, the coil is fixed by the contraction force of the heat-shrinkable tube, eliminating the need for a bobbin, so the diameter of the coil can be reduced.
Thereby, the diameter of the hole formed in the cavity resonator can also be made smaller. Therefore, it becomes possible to increase the Q value more than before.

Further, if the hole diameter is the same, the diameter of the sample tube can be increased by the thickness of the bobbin, so a large sample can be accommodated, sensitivity can be improved, and sample preparation is facilitated.

Furthermore, by providing sleeves at both ends of the high-frequency coil, it is possible to reduce microwave leakage due to the high-frequency coil, and the lead wires between the connector and the high-frequency coil can be made short (as a result, microwave leakage due to the lead wires can be reduced).

Furthermore, since the heat-shrinkable tube placed over the outer periphery of the coil can be used as a gas passage, it is no longer necessary to insert a new vibrator to pass gas for sample heating into the coil, and the configuration can be changed. Simplification can be achieved.

[Brief explanation of the drawing]

FIG. 1 is an enlarged cross-sectional view of essential parts showing an example of ESR equipment according to the present invention, FIG. AA of the diagram
FIG. 1: Cavity resonator 2: Waveguide 3: High frequency coil 4: Heat shrinkable tube 5; Jig 6a, 6b Ni sleeve 7a, 7b: Insertion hole 8: Screw 9a, 9b: Support 10: Sample 11: Sample Tube 12; Holder 13; Sample stage 14a, 14b: Connector 15a, 15b: Lead wire

Claims (1)

[Claims] END by incorporating a high frequency coil into the cavity resonator
In the electron spin resonance device that made OR measurement possible,
Electron spin resonance characterized in that a heat-shrinkable tube is placed over the outer periphery of the high-frequency coil, and the heat-shrinkable tube is contracted to fix the high-frequency coil, thereby eliminating the need for a bobbin placed inside the high-frequency coil. Device.