JPS59211883A - Neutron detector - Google Patents

Abstract

PURPOSE:To certainly and electrically connect an electrode and a lead wire, by connecting the lead wire to the electrode through a solder material and a metal foil by spot welding. CONSTITUTION:An anode lead wire 4a is clamped between an Ni-foil 21 and the folded end part 21a of said foil 21 and a solder material 22 such as silver solder is held between the foil 21 and an anode 1a comprising an A material while the foil 21 and the anode 1a are subjected to spot welding. Whereby, the wire 4a and the anode 1a are certainly and electrically connected. The connection of a cathode and a cathode lead wire is similarily performed and the signal interruption of a neutron detector is prevented.

Description

[Detailed description of the invention] This invention relates to a neutron detector.

Conventionally, as a connection structure between an electrode and a single tone wire of a neutron detector for nuclear measurement outside the reactor, the structure shown in FIG. 1 has been used. In the figure, 1a is a cylindrical anode whose inner surface is coated with a neutron-sensitive substance 8, 1b is a cathode shaped like a circle f+9i, whose outer surface is coated with a neutron-sensitive substance 8 and inserted into the anode la, 9 is the space ζ between the anode 1a and the cathode 1b.
The sealed gas to be ionized, 4a an anode lead wire for applying an external iL'jJ voltage to the anode 1a, and 2a electrically connected to the anode lead wire 4a by welding or the like. Further, 4b is a cathode lead wire for taking out an electric signal proportional to neutrons from the cathode 1b to the outside, and the cathode lead wire 4b takes out the electric signal from the cathode 1b to the outside via the annular cathode end ring 2b. It is connected to a minute current measurement circuit for

The cathode end ring 2b is electrically connected to the cathode 1b by fitting, and is electrically connected to the cathode lead wire 4b by spot welding or the like.

3a.

3b is a ring-shaped alumina ceramic, these are anode 1
a, an anode section consisting of left and right anode end rings 2a + anode lead wire 4a and a cathode 1b.

This is for electrically insulating the left and right cathode end rings 2b and the cathode portion consisting of the cathode lead wire 4b from each other, and also electrically insulating each from the class 5.

Next, the operation will be explained. A high voltage of 800 V DC is applied to the anode 1a from the outside g++ via the anode lead iJA 4a and the anode end ring 2a, and when neutrons are incident on this neutron detector in this state, the inner surface of the anode 1a or the outer surface of the cathode 1b For example, B is a neutron and nuclear reaction (B+rr
−= Li +α). At this time, No. 1: anode 1a due to L'r and α particles.

The ionized gas 9 at the cathode tbl:l is ionized. The cations and electrons generated by this ionization are the cathode 1b and the anode 1a, respectively.
As a result, a current flows to the minute current measuring circuit connected to the outside of the quadry 1 and the wire 4b. Since this current is based on the reaction described above, in this minute current measurement circuit, the current proportional to the neutron flux is divided by 1.

The signal current handled at this time is approximately 10. A~5XlO
-' A minute current. Therefore, when handling such a minute current, it is necessary to keep the connection between the anode lead wire 4a and the anode 1a and the connection between the cathode lead wire 4b and the cathode 1b electrically perfect. On the other hand, this neutron detector is exposed to a neutron flux atmosphere, so the material that makes up the neutron detector is made of materials that have low absorption of neutrons in order to reduce activation by neutrons and to measure neutrons efficiently. materials need to be used.

- Al is a material that satisfies the requirements listed in A7!
It is used as the anode la and cathode 1b of a neutron detector. But A7! When welding or brazing is performed in connection with other metals, intermetallic compounds are often formed, resulting in only brittle connections. Therefore, direct spot welding is not performed when connecting the anode 1a and the anode lead wire 4a and the cathode 1b and the cathode lead wire 4b of a conventional neutron detector. Ti History Theanod En 1 Ring 2
A method was used in which the electrodes were electrically connected by spot/8 contact and fitting this into the Ap anode 1a.

Conventional neutron detectors are configured as described above, so a reliable electrical connection cannot be obtained at the connection between the end ring and the electrode, and the connection may be broken if vibration or impact is applied. This has the drawback of causing interruptions in the signal current.

This invention was made in order to eliminate the drawbacks of the conventional ones as described in 2. Electrode-1: In connection with the wire, the wire is connected to the electrode through a brazing material and gold E 7I'J. By spot welding, the 711 pole and the lead wire can be electrically connected reliably, preventing signal interruption. The purpose is to convert the neutron detector into JIM.

An embodiment of the present invention has been described above with reference to the drawings.

FIGS. 2 and 3 show one embodiment of the present invention, and in the figures, the same reference numerals as in FIG. 1 indicate the same or corresponding parts.

2J is a 112 temporary N formed using Ni!
Wj, 22 is a wax shrine, la is an anode electrode, 4a is an anode lead wire, and 2a is a γ]1en'1 link. A
The anode 1a of the 1st section and the 1st electrode 1a are connected as shown in the figure in order to ensure electrical connection. That is, η of 21 “bi GB 212
A wax pad 22 is inserted between the anode 1 and the anode NJAla, and N17^21 is spot welded to the anode 1a in this state. Although not shown, the connection 11 between the negative 1 nearer J 7ii 4 11) and the cathode lead wire 4b is also made in the same way. In this case, according to the results of our experiments, tM wax (13Δg 8) was the most suitable for the brazing filler metal 22.

The device of this embodiment employs a structure in which N17^21 and the anode 1a are connected by spot welding in the connection between the annotary 1 wire 4a and the anode 1a. (A true electrical connection can be obtained. Note that gold compounds are formed locally in the spot welding/81 region between this 15AI anode 1a and the brazing filler metal 22, but spot welding can be performed at many locations.) The structure is such that a real connection is possible.
It is something that can be done.

Note that in the above embodiment, the metal ';Fi
When 21 is in contact with the anode 1a by Subono 1~/8, it is possible to apply a brazing material to the metal 7tJ2 or plate a waxy plate (possibly, a waxy plate may be interposed separately). It is also possible to spot weld the metal foil 21 to the +*ta instead of the metal foil 21.Also, the metal foil 21 can be provided by making the metal foil 22 into a foil shape. It is also possible to connect i1J. Naohe β-glue using one wire, brazing filler metal 22 and metal 9fi2
Do not install 1 (item) ＼ I-made lead wire)
It is also possible to connect directly to +J''ii, but in this case the Al wire has the disadvantage of being weak.

As described above, according to this invention, like Al, all 1ijS
When connecting electrodes and lead wires that are likely to generate interstitial compounds, metal foil is spot-welded to the electrodes via a brazing filler metal.
Since the wire is bonded to the metal foil, a reliable electrical connection can be obtained with a simple structure.

[Brief explanation of drawings]

Figure 1 is a half-11i side view of a conventional neutron detector;
The figure is an enlarged sectional view of an electrode portion of a neutron detector according to an embodiment of the present invention, and FIG. 3 is a perspective view thereof. 1a... Anode electrode, ■b... Cathode electrode, 4a, 4b
... Lead wire, 21 ... Metal foil, 22 ... Brazing material. In the drawings, the same reference numerals indicate the same or equivalent parts. Agent Masuo Oiwa Figure 1, Figure 2, hand f, IC sleeve positive embryo (Jishi), Showa year, month' I+ 11° Director-General of the Agency 1, ゛1 eye'1- display f'+' request Showa 58-
87856 Uh. 2. Name of invention neutron detector; 3. Ura IF representative piece 111 Jin 8 part 5, claims column and detailed explanation of the invention column 6 of the subject specification of Ni positive, content of amendment + 1 + appendix of claims of the specification Correct as follows. (2) "1 metal foil" on page 5, line 10 of the specification is replaced with "gold IM9"
δ or metal 2δ only”. (3) On page 7, line 19, "1-metal 28" is corrected to "1-or direct metal foil." F Claims (1) AI! or a dog made of An alloy and connected to a high voltage source,
An ex-core nuclear measurement device comprising an electrode and a kN pole connected to a minute current measurement circuit through an A/or A1 alloy crack, and which generates a current proportional to the neutron flux when neutrons are incident between the two electrodes. A neutron detector for use in a neutron detector is characterized in that a metal foil is spot-welded to each of the electrodes via a wax wire, and a wire is fixed to the metal foil. Neutron detector.

Claims (1)

[Claims] (Equipped with an anode electrode made of 1,1/L or AA alloy and connected to a high voltage source, and a cathode electrode made of 7B or A2 alloy and connected to a minute current measurement circuit, with a neutral r In a neutron detector for ex-core nuclear measurement that generates a current proportional to the neutron flux when neutrons are incident, a metal foil is spot-welded to each of the electrodes via a brazing metal, and a lead is fixed to the metal foil. A neutron detector characterized by a wire.