CN2240725Y - Broad brush pen type radiation imaging gas detector - Google Patents

Abstract

The utility model relates to a broad brush pen type radiation imaging gas detection apparatus, comprising a pen type gas ionization chamber, an incident window, a mother plate of the ionization chamber and a lateral plate. The incident window is positioned on the front end of the detection apparatus, and the pen type gas ionization chamber is arranged in a single-row way in the detection apparatus. Broad brush pen type ionization chamber modules can be tightly arranged in a single-row way into a true linear array to basically eliminate the scanning imaging misplacement phenomenon of the existing techniques. The pen type gas ionization chamber is composed of an incident window, the external cylinder of the thin wall of the ionization chamber, an air duct, an insulator ceramic head and an insulator top cover. The incident window is positioned on the end part of the pen type gas ionization chamber and corresponds to the incident window of the detection apparatus, and an insulator ceramic tube and an insulator sealing head are arranged between the air duct and the external cylinder.

Description

Spread pen formula radiation imageable gas detection apparatus

The utility model relates to a kind of spread pen formula radiation imageable gas detection apparatus of real linear array, belongs to the radiation checking technical field.

At present the numeral that large-sized object the is carried out radiation detection system that takes pictures realizes scanned imagery with detector array, usually as Chinese patent " gas-ionization high energy X, γ radiation imageable array detecting device ", the patent No. 9310272814.Its structure as shown in Figure 1, among the figure, the 1st, ray entrance window, the 2nd, pressure-resistant seal housing, the 3rd, electrode slice supporter, the 4th, electrode slice, the 5th, insulator, the 6th, wireway.Its design feature is that module housing is an one-piece construction that high pressure is airtight, inflates whole module by wireway.Inside modules is separated into the useful space by electrode slice and is parallel to each other and the bar shaped ionization chamber of adjacent arrangement, and constituting with the module is the ionization chamber array of unit.Electrode slice is spaced with negative high voltage sheet and collection pole piece, and each is collected pole piece and links to each other the output of assurance charge signal with an insulator.The shortcoming that adopts this kind structure is module edge to be existed cause the dead band (the high pressure air-tight casing is at the thickness at this place) that pixel is lost, thereby can't form the linear array of real detector when the multidetector module is arranged and alternately arrange about needing.In addition,, need be inflated to tens atmospheric pressure, thereby the locular wall of modular cartridge thicker (centimetre magnitude) for improving detection efficiency, about the distance of arranging big, make to have inconsistent phenomenon in the scanned imagery.Because radiation source is point source, left and right sides detecting module and radiation source form certain angle, make that the diverse location at the container thickness direction has different image dislocation, and therefore the dislocation of whole scanning image can not be eliminated fully with image processing method.The similar system of France adopts the thin proportional chamber of wall thickness, but still can't be arranged in real linear array.

The purpose of this utility model is the spread pen formula radiation imageable gas detection apparatus of a kind of real linear array of design, adopts discrete pen type thin-walled gas ionization chamber to form spread pen formula modular structure.Since the cross section of each ionization chamber unit only several millimeters square, when being inflated to tens atmospheric pressure, wall thickness also only needs a few tenths of a mm, therefore can one adjacent one be arranged in real linear array, problem of misalignment when fundamentally eliminating scanned imagery, the advantage that the retained gas bulk detector is simple in structure again, the life-span is long and noise is little.

The spread pen formula radiation imageable gas detection apparatus of the utility model design comprises incidence window, signal processing module, ionization chamber motherboard, side plate, pen type ionization chamber.The cross section of pen type ionization chamber can be a rectangle, also can be circular or other polygons.Incidence window is positioned at the front end of sniffer, and signal processing module places the other end, and the pen type ionization chamber single file is arranged in the middle part of sniffer.The arrangement mode of ionization chamber when the cross section be straight line during for rectangle, when cross section when being circular, its arrangement mode can be a straight line, also can be zigzag.Ionization chamber is fixed on the ionization chamber motherboard by the fabricated section on it, and the ionization chamber motherboard is by the side plate relative fixed of fixed leg in sniffer.Above-mentioned pen type ionization chamber is made up of entrance window, ionization chamber thin-walled urceolus, wireway, insulator porcelain head and insulator top cover.Incidence window is positioned at the end, relative with the incidence window of sniffer, one end of wireway is by set collar and ionization chamber urceolus relative fixed, the other end of wireway stretches out outside the ionization chamber, the position is insulator porcelain pipe and insulator end socket between wireway and the urceolus, the insulator porcelain tube end is the insulator top cover, and the outer wall of ionization chamber urceolus is provided with fabricated section.

Owing to adopt the thin-walled separate structure, the radiation detector array of really arranging in a line is formed in the tight arrangement of practicable spread pen formula, and the gained image is without any inconsistent phenomenon.This array can be expanded up and down continuously, increases the pen type detector cells arbitrarily and does not have any pixel dead band.Aspect spatial resolving power, in practicality, can detect diameter and be the tagger that 0.8 millimeter iron wire and thickness are 0.3 millimeter, satisfy the radiation imageable requirement of large-sized object.And domestic and international present existing gas detector array all is a modular organization, because wall thickness, as be arranged in a straight line, will there be sizable pixel dead band at two intermodules.For making pixel continuous, the dead band is avoided in the left-right and front-back cross arrangement of having to, thereby causes the image dislocation that can't proofread and correct.And, pass through the strict and pulses of radiation frequency matching of time of two row detectors of left and right sides cross arrangement in order to make testee, also require the speed of huge transfer system to be accurate to 1% magnitude, involve great expense.The utility model can strict be had an X-rayed all pixels on the same cross section simultaneously owing to can be arranged in real linear array during the scanning testee, do not require the transfer rate and the pulses of radiation Frequency Synchronization of testee.The speed accuracy of transfer system is only required and is reached 10% magnitude, greatly reduces the cost of large-sized object scanned imagery system.

Description of drawings:

Fig. 1 is the prior art structural representation.

Fig. 2 is the gas detection apparatus structural representation of the utility model design.

Fig. 3 is the pen type ionization chamber structural representation that is exclusively used in this sniffer.

Fig. 4 is the vertical view of Fig. 3.

Fig. 5 is the utility model and prior art effect comparison.

Fig. 6 is two kinds of arrangement modes of the pen type ionization chamber of round section in the utility model.

Below in conjunction with accompanying drawing, introduce content of the present utility model in detail.Among Fig. 2, Fig. 3, the 21st, incident luffer boards, the 22nd, pen type ionization chamber, the 23rd, signal processing module, the 24th, fixed leg, the 25th, sniffer side plate, the 26th, the motherboard of assembling ionization chamber, the 27th, fabricated section.The structure of each pen type ionization chamber as shown in Figure 4.Among Fig. 4, the 31st, the wireway ionization chamber collector of holding concurrently, the 32nd, insulator top cover, the 33rd, insulator porcelain pipe, the 34th, insulator end socket, the 35th, ionization chamber urceolus, the 36th, wireway set collar, the 37th, entrance window.

As shown in the figure, 22 1 adjacent one of pen type ionization chamber is arranged in detector array, is fixed on the motherboard of being made by insulating material 26.Incident luffer boards 21, two side plates 25 and four fixed legs 24 constitute the containment vessel of sniffers, and the ionization chamber motherboard is fixed on two fixed legs of contact with it.The characteristics that adopt this structure are to make the height of containment vessel side plate consistent with the height of detector array, and need not add any fender at the upper and lower side of containment vessel.When adopting a plurality of modules to constitute real continuous detector linear array,, can realize the adjacent arrangement of detector equally at the module joining place like this owing to do not cause the dead space volume that pixel is lost between the module.During detector module work, the urceolus of the pen type ionization chamber in the sniffer adds negative high voltage, and the containment vessel of sniffer is in zero potential.The effect of signal processing module 23 is charge signals of handling the output of pen type ionization chamber collector, is translated into the flat-top voltage signal that back level data Acquisition Circuit can be analyzed.

The design feature and the principle of work of pen type ionization chamber are as follows: hold concurrently collector 31, insulator top cover 32, insulator porcelain pipe 33 and insulator end socket 34 of the wireway in the ionization chamber constitutes insulators, guarantee the impermeability of ionization chamber inside with ionization chamber urceolus 35 and ionization chamber entrance window 37, make hold concurrently collector and ionization chamber urceolus of wireway keep good electrical isolation simultaneously.The wireway set collar 36 of stupalith is maintained fixed the position of wireway, has also guaranteed the electrical isolation of wireway and urceolus simultaneously.Fabricated section 27 can accurately be installed on the motherboard 26 the pen type ionization chamber.During ionization chamber work, inside is filled the working gas of certain air pressure with, and the ionization chamber urceolus adds negative high voltage, and makes the axis direction of ionization chamber consistent with the direction of beam.Beam after the testee scanning is passed the ionization chamber entrance window, in the working gas of ionization chamber inside, cause ionization, the ionization electric charge is drifting about under the effect of electric field between collector and the urceolus, thereby on collector, form the charge signal that size is directly proportional with the incident ray beam intensity, through signal Processing, obtain the testee image.

Fig. 5 is the utility model and the contrast of prior art scanning image.Wherein A is existing boxlike overall gas detector scanning image, has inconsistent phenomenon; B is the scanning image of spread pen formula radiation imageable gas detection apparatus gained of the present utility model.

Pen type ionization chamber of the present utility model also can adopt circle or other polygonal cross-sections except that adopting the square-section.The pen type ionization chamber production technology of round section (Fig. 6 A) is the simplest, but the detecting window area is π/4 of rectangle, and detection efficiency is low slightly.Adopt the serrate of Fig. 6 B to arrange, when same pixel pitch, can enlarge detector area.When serrate was arranged, adjacent two ionization chambers were at a distance of about 1/2 pixel only, and to the subtended angle of radiation source 0.016 degree only, the image that causes in container both sides dislocation is not more than 1/5 pixel, can ignore in the practicality.

Claims (1)

1. a spread pen formula radiation imageable gas detection apparatus comprises incidence window, signal processing module, ionization chamber motherboard, side plate, it is characterized in that also comprising pen type ionization chamber; Incidence window is positioned at the front end of sniffer, signal processing module places the other end, the pen type ionization chamber single file is arranged in the middle part of sniffer, is fixed on the ionization chamber motherboard by the fabricated section on the ionization chamber, and the ionization chamber motherboard is by the side plate relative fixed of fixed leg and sniffer; Described pen type ionization chamber is made up of entrance window, ionization chamber thin-walled urceolus, wireway, insulator porcelain head and insulator top cover; Incidence window is positioned at the end, relative with the incidence window of sniffer, one end of wireway is by set collar and ionization chamber urceolus relative fixed, the other end of wireway stretches out outside the ionization chamber, the position is insulator porcelain pipe and insulator end socket between wireway and the urceolus, the insulator porcelain tube end is the insulator top cover, and the outer wall of ionization chamber urceolus is provided with fabricated section.

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