A low-background liquid scintillation spectrometer

Abstract

The present invention provides a low-background liquid scintillation spectrometer, comprising a packaging shell, a detection mechanism installed at the bottom of the packaging shell for detecting a sample to be tested in a sample bottle; a sampling mechanism installed at the top of the packaging shell for transferring the sample bottle to the detection mechanism; a sample carrier located between the detection mechanism and the sampling mechanism, the sample carrier being provided with a sample slot for placing the sample bottle; an additional sample loading mechanism installed on the sample carrier and pulled in and out of the packaging shell, the additional sample loading mechanism being provided with a sample slot for placing an emergency sample bottle. The low-background liquid scintillation spectrometer integrates functions such as automatic injection of large sample volumes, automatic sample addition, automatic closing of the lead chamber, automatic loading and exiting of samples, automatic destaticization of sample bottles, automatic temperature control of samples and detection areas, expedited detection of any sample position, and automatic additional sample addition, with a high degree of automation and a compact structure.

Description

Technical Field

[0001] The present invention relates to the technical field of low-background liquid scintillation spectrometers, in particular to a low-background liquid scintillation spectrometer. Background Art

[0002] Low background liquid scintillation spectrometer is a liquid scintillation counter used for measuring ultra-low level α and β radioactivity. It is mainly used for low level radioactivity in various environmental samples such as water, soil, organisms, aerosols, etc. 3 H. 14 The measurement of nuclides such as C plays an important role in nuclear waste disposal, environmental protection, archaeological dating, medical analysis, food safety, and scientific research. Low-background liquid scintillation spectrometers use liquid scintillators to receive radiation from the substance being measured and convert it into fluorescent photons. Photoelectric devices then amplify and multiply the light to form pulses. Electronic circuits and software then process the light to produce a series of waveforms, completing the measurement of the substance.

[0003] The mainstream ultra-low-background liquid scintillation spectrometers currently on the market include the SLA series from PE in the United States, Hidex in Finland, and Shanghai Xinman. The PE 2910TR can accommodate up to 408 standard 20ml bottles or 702 7ml bottles. To insert a sample rack, the instrument's top cover must be manually opened, supported by a side brace, and the rack filled with sample bottles placed into the sample well and the lid closed. After the sample is placed, the instrument automatically moves the rack to the sample loading position for loading and testing after the sample is allowed to sit in the dark for 8 hours. Ventilation vents are located on both the front and rear surfaces of the sample area, providing ionized air to eliminate static electricity throughout the space. Cooling air also enters through these vents to cool the sample. However, the instrument has the following disadvantages: (1) The sample rack can only be loaded when it moves to the sample inlet in the middle of the rear, and arbitrary position detection or queue-jumping detection cannot be achieved; (2) When loading samples, the lid must be opened manually and supported with a support rod or with one hand holding the lid and the other hand placing the sample rack, resulting in a low degree of automation; (3) If it is necessary to temporarily add samples, the entire lid must be opened, and the placed samples must be placed back to stand still and away from light, making it inconvenient to temporarily add samples; (4) Ionized air is blown to the entire sample loading area to eliminate static electricity, but it is not reliable to specifically de-staticize each bottle; (5) The sample rack can only load the sample into the lower detection chamber after it sends the sample to the middle position of the rear of the sample area step by step through the transmission belt and ratchet, resulting in a slow loading speed.

[0004] Finnish Hidex 300SL & 600SL instruments load samples using a suction cup assembly that moves in three dimensions, enabling expedited testing at any position. However, to change sample bottles of different sizes, the entire sample tray must be replaced, making it inconvenient to use. To temporarily add samples, the entire tray must also be opened, and the already placed samples must be placed back in a dark place, making it inconvenient to temporarily add samples.

[0005] Shanghai Xinman's LSA2000, which is already on the market, is a medium-volume instrument (260 20ml sample bottles) with some automation capabilities. Shanghai Xinman's patent CN118011455A, a fully automatic liquid scintillation spectrometer, discloses an instrument with a 400-sample capacity. The instrument has the following problems: (1) The sample tray is a layout of two 10*20 trays, and the tray size is at least 0.65m*1.3m. It needs to be pulled out manually by the handle, which is inconvenient (it needs to be pulled and moved back at the same time). According to the principle of ergonomics, it is difficult to place the sample bottle at a distance of more than 0.5m from the body, and the operating experience is poor; (2) There are four linear modules that move the sample vertically, which can easily cause suffocation and waste costs; (3) To replace sample bottles of different sizes, the entire sample tray must be replaced, which is inconvenient to use; (4) If it is necessary to temporarily add samples, the entire tray must be opened, and the samples that have been placed must be placed in a dark place again, which is inconvenient to temporarily add samples; (5) There is no temperature control and cooling device for the sample and the detection room, which affects the detection performance. Summary of the Invention

[0006] In response to the deficiencies in the prior art, the present invention provides a fully automatic low-background liquid scintillation spectrometer that integrates functions such as automatic sampling of large sample volumes, automatic sample addition, automatic closing of the lead chamber, automatic loading and unloading of samples, automatic destaticization of sample bottles, automatic temperature control of samples and detection areas, expedited detection of any sample position, and automatic additional sample addition.

[0007] The technical solution adopted to achieve the above-mentioned purpose of the present invention is:

[0008] A low-background liquid scintillation spectrometer comprises at least a packaging shell, wherein the packaging shell is installed with:

[0009] A detection mechanism, which is installed at the bottom of the packaging shell and is used to detect the sample to be tested in the sample bottle;

[0010] A sampling mechanism, which is installed at the top of the packaging shell and is used to transfer the sample bottle to the detection mechanism;

[0011] A sample carrier, located between the detection mechanism and the sampling mechanism, the sample carrier being provided with a sample slot for placing a sample bottle;

[0012] The additional sample loading mechanism is installed on the sample carrier and is pulled in and out of the packaging shell. The additional sample loading mechanism is provided with a sample slot for placing an emergency sample bottle.

[0013] The additional sample loading mechanism includes a sample box and a second side sealing plate. The sample box is provided with at least one sample slot of different sizes. The sample box is slidably connected to the sample carrier. A sample box inlet and outlet are provided on the shell wall of the packaging shell at the sample box. The sample box slides in and out of the sample box inlet and outlet; the second side sealing plate extends from the sample box inlet and outlet and is fixedly connected to the sample box, and the second side sealing plate is sealed around the sample box inlet and outlet.

[0014] The bottom of the emergency injection bottle is detachably fixed with an external standard source, and the bottom of the sample slot on the additional sample loading mechanism is correspondingly provided with a pit, the shape and size of the pit match the shape and size of the external standard source. When the emergency injection bottle with the external standard source is placed in the sample slot on the additional sample loading mechanism, the external standard source is located in the pit at the bottom of the sample slot.

[0015] The sample carrier includes a sample tray, which is assembled from multiple horizontal trays along the longitudinal or transverse direction, and each horizontal tray is provided with a row of sample slots; the size of the sample slots on the horizontal tray matches the size of the sample bottle, and the external shapes and sizes of horizontal trays with different sample slot sizes are consistent.

[0016] The sample tray also includes a bottom support plate. The two side surfaces of the horizontal tray are corrugated. Guide positioning columns are fixedly provided on the bottom support plate. The horizontal tray is assembled and placed on the bottom support plate and clamped between the guide positioning columns.

[0017] A draw-out opening is provided on the shell wall of the packaging shell at the location of the sample carrier, and the sample carrier is slidably connected to the packaging shell and enters and exits the packaging shell through the draw-out opening.

[0018] The sampling mechanism includes a three-dimensional motion module, a sampling rod, a vacuum suction cup, a vacuum pump, and a sensing and control component. The three-dimensional motion module is installed at the top of the packaging shell. The sampling rod is vertically installed on the three-dimensional motion module and moves with the three-dimensional motion module in the upper, lower, left, right, front and back planes. The vacuum suction cup is fixed downward at the bottom of the sampling rod. The vacuum suction cup is connected to the vacuum pump. The sensing and control component is also connected to the vacuum pump. The vacuum pump is controlled by the sensing and control component, thereby controlling the vacuum suction cup to absorb or put down the sample bottle.

[0019] The detection mechanism includes a detection chamber, a light shield, a lead chamber, a lead plug and a lead plug driving mechanism. A sample detection port is provided on the detection chamber, the light shield covers the outside of the detection chamber, the lead chamber is fixedly installed on the top of the detection chamber, and a sample inlet is provided on the lead chamber above the sample detection port. The lead plug closes the sample inlet on the lead chamber from the side, and the lead plug and the lead chamber are movably connected. A lead plug driving mechanism is connected between the lead plug and the lead chamber, and the lead plug is driven to open and close by the lead plug driving mechanism, thereby closing or exposing the sample inlet on the lead chamber.

[0020] The sample carrier is provided with a static elimination mechanism at the sample inlet. When each sample bottle enters the sample inlet, static electricity is eliminated by the static elimination mechanism.

[0021] A refrigeration component is installed on the rear wall of the packaging shell; a cooling and heat-insulating component is installed around the sample carrier and the detection mechanism in the packaging shell, and the refrigeration component is packaged in the cooling and heat-insulating component.

[0022] Compared with the prior art, the technical solution provided by the present invention has the following advantages: (1) The low-background liquid scintillation spectrometer provided by the present invention integrates the functions of automatic sampling of large sample volumes (more than 400 sample positions), automatic sample addition, automatic closing of the lead chamber, automatic loading and unloading of samples, automatic destaticization of sample bottles, automatic temperature control of samples and detection areas, expedited detection of any sample position, automatic addition of samples, etc. It is a fully automatic low-background liquid scintillation spectrometer with a high degree of automation and a compact structure.

[0023] (2) In the detection mechanism of the present invention, the lead plug driving mechanism drives the lead plug to open and close automatically, thereby realizing automatic sampling, and an electrostatic elimination mechanism is provided above the sample inlet and outlet to eliminate static electricity for each sample bottle individually, making the static elimination operation more reliable.

[0024] (3) The sampling mechanism of the present invention adopts a combination of a three-dimensional motion module and a vacuum suction cup. The three-dimensional motion module can realize sampling at any position for expedited testing. At the same time, a sliding guide block is installed at the bottom of the guide rail assembly of the Z-axis motion module to prevent the sampling rod from shaking during operation.

[0025] (4) The sample carrier rack of the present invention can realize the loading and sampling of more than 400 sample positions, and at the same time, the sample tray is automatically driven in and out by the sample driving mechanism to realize the automatic loading and unloading of samples; at the same time, the sample tray is assembled from multiple horizontal trays. When it is necessary to replace sample trays of different specifications, it is only necessary to remove and install the horizontal tray, and there is no need to take out the entire sample tray for replacement, thereby realizing a compatible design for sample bottles of different sizes, and it is possible to place any number of sample bottles of different sizes on the same sample tray, making it convenient for customers to load more different types of samples to be tested at one time.

[0026] (5) The present invention is provided with an additional sample loading mechanism, which can realize temporary additional samples without opening the entire tray, avoiding the need to re-place the placed samples in the dark; and the bottom of the emergency injection bottle is detachably fixed with an external standard source, which can be loaded, calibrated and taken out together with the emergency injection bottle, facilitating the calibration of the instrument during the detection process.

[0027] (6) The present invention is also provided with a refrigeration mechanism to cool the sample and the detection mechanism, and the refrigeration efficiency is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of the external structure of the low-background liquid scintillation spectrometer provided by the present invention Figure 1 ;

[0029] Figure 2 Schematic diagram of the external structure of the low-background liquid scintillation spectrometer provided by the present invention Figure 2 ;

[0030] Figure 3 A schematic diagram of the internal structure of the low-background liquid scintillation spectrometer provided by the present invention;

[0031] Figure 4 Schematic diagram of the structure of the detection mechanism of the present invention;

[0032] Figure 5 Schematic diagram of the structure of the detection chamber of the detection mechanism of the present invention;

[0033] Figure 6 Schematic diagram of the structure of the lead chamber of the detection mechanism of the present invention;

[0034] Figure 7 Schematic diagram of the structure of the sealing member in the detection mechanism of the present invention;

[0035] Figure 8 This is a schematic diagram of the structure after the sealing member is installed on the lead chamber of the present invention;

[0036] Figure 9 Schematic cross-section of the detection mechanism when the lead plug is closed in the present invention;

[0037] Figure 10 It is a cross-sectional schematic diagram of the detection mechanism when the lead plug is opened in the present invention;

[0038] Figure 11 It is a structural schematic diagram of the sampling mechanism of the present invention;

[0039] Figure 12 A block diagram showing the connections between the vacuum pump, vacuum chuck, and sensing and control components of the present invention;

[0040] Figure 13 Schematic diagram of the structure of the sample carrier in the present invention;

[0041] Figure 14 Schematic diagram of the structure of the sample tray in the present invention;

[0042] Figure 15 This is a schematic diagram of the structure of a horizontal tray with a sample slot size of 20 mm in the present invention;

[0043] Figure 16 This is a schematic diagram of the structure of a horizontal tray with a sample slot size of 4-7 mm in the present invention;

[0044] Figure 17 Schematic diagram of the connection between the sample tray and the sample drive mechanism in the present invention;

[0045] Figure 18 It is a structural diagram of the additional sample loading mechanism in the present invention;

[0046] Figure 19 This is a schematic diagram of the external standard source being fixed to the bottom of the emergency injection bottle and placed in the recess at the bottom of the sample tank in the present invention;

[0047] Figure 20 This is a schematic diagram of sampling for emergency testing of additional samples in the present invention;

[0048] Figure 21 A schematic diagram of a sample bottle passing through a static elimination mechanism in the present invention;

[0049] Figure 22 Schematic diagram of the packaging of the cooling and heat insulation component of the present invention;

[0050] In the figure: 100-sample bottle, 200-emergency sampling bottle, 1-packaging shell, 2-detection mechanism, 21-detection chamber, 211-sample detection port, 22-light shield, 23-lead chamber, 231-sample inlet, 232-groove, 24-lead plug, 251-external drive linear motor, 252-lead plug linear slide, 253-lead plug slider, 26-seal, 3-sampling mechanism, 31-three-dimensional motion module, 32-sampling rod, 33-vacuum suction cup, 34-vacuum pump, 35-gas storage tank, 36-sliding guide block, 4-sample carrier, 41-fixed support plate, 411-opening, 42-sample linear slide, 43-sample tray, 431-bottom support Plate, 432-horizontal tray, 433-guide positioning column, 44-sample driving mechanism, 441-sample driving motor, 442-driving gear, 443-driven gear, 444-synchronous gear belt, 445-driving block, 45-first side sealing plate, 46-RFID tag position, 5-additional sample loading mechanism, 51-sample box, 52-second side sealing plate, 531-mounting plate, 532-electric push rod, 533-additional sample linear slide, 534-additional sample slider, 54-external standard source, 6-static elimination mechanism, 7-refrigeration mechanism, 71-refrigeration component, 72-cooling and heat insulation component, 8-industrial computer, 9-RFID electronic tag identification module. DETAILED DESCRIPTION

[0051] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0052] The structure of the low background liquid scintillation spectrometer provided by the present invention is as follows Figure 1-Figure 3As shown, it includes a packaging shell 1 and a detection mechanism 2, a sampling mechanism 3, a sample carrier 4, an additional sample loading mechanism 5, an electrostatic elimination mechanism 6, a refrigeration mechanism 7 and an industrial computer 8 installed in the packaging shell.

[0053] The detection mechanism is installed at the bottom of the packaging shell and is used to detect the sample to be tested in the sample bottle 100. In this embodiment, the detection mechanism includes a detection chamber 21, a light shield 22, a lead chamber 23, a lead plug 24 and a lead plug driving mechanism, such as Figure 4 The detection chamber is provided with a sample detection port 211, as shown. Figure 5 As shown, the sample bottle is placed into the detection chamber through the sample detection port. The detection module in the detection chamber detects the sample to be detected in the sample bottle. The structure of the detection chamber is an existing conventional structure and will not be described in detail here. The light shield is covered on the outside of the detection chamber to shield the entire detection chamber from light and avoid interference from cosmic rays. The lead chamber is fixedly installed on the top of the detection chamber, and a sample inlet 231 is provided on the lead chamber above the sample detection port. Figure 6 As shown. The lead plug closes the sample inlet on the lead chamber from the side, and the lead plug and the lead chamber are movably connected. A lead plug driving mechanism is connected between the lead plug and the lead chamber, and the lead plug is driven to open and close by the lead plug driving mechanism, thereby closing or exposing the sample inlet on the lead chamber. Specifically, the lead chamber is provided with grooves 232 around the sample inlet. Figure 6 , a seal 26 is installed on the groove, such as Figure 7 and Figure 8 As shown, when the lead plug closes the sample inlet on the lead chamber from the side, the lead plug fits tightly with the seal to avoid the presence of a gap at the connection between the lead chamber and the lead plug, which causes light to enter the detection chamber from the gap during the detection process, thereby playing a light-shielding role. Furthermore, the connection between the lead plug and the lead chamber adopts a taper fitting design to reduce the friction of parts, especially the friction on the seal, and improve the service life of the parts. Specifically, the lead plug driving mechanism includes an external drive linear motor 251, a lead plug linear slide 252 and a lead plug slider 253. The light shield and the lead chamber are relatively fixed. For ease of installation, the lead plug linear slide is fixed on the light shield and parallel to the lead plug. The lead plug slider is slidably installed on the lead plug linear slide. The lead plug is fixedly connected to the lead plug slider. The fixed end of the external drive linear motor is fixed to the end of the lead plug linear slide on the light shield away from the lead plug, and the movable end of the external drive linear motor is connected to the lead plug or the lead plug slider. The external drive linear motor drives the lead plug to move horizontally, realizing automatic opening and closing of the lead plug, as shown in FIG. Figure 9 and Figure 10 Preferably, the connection between the lead chamber and the lead plug is set as a stepped interlocking structure, and silicone or other sealing strips are added at the connection between the lead chamber and the lead plug for reliable sealing.

[0054] The sampling mechanism is installed at the top of the packaging shell and is used to transfer the sample bottle to the sample detection port of the detection mechanism. In this embodiment, the sampling mechanism includes a three-dimensional motion module 31, a sampling rod 32, a vacuum suction cup 33, a vacuum pump 34, and a sensor and control component, such as Figure 11 As shown. The three-dimensional motion module is installed at the top of the packaging shell. The three-dimensional motion module includes an X-axis motion module arranged horizontally, a Y-axis motion module arranged vertically, and a Z-axis motion module arranged vertically. The X-axis motion module is fixed in the packaging shell, the Y-axis motion module is installed on the X-axis motion module and can move horizontally, and the Z-axis motion module is installed on the Y-axis motion module and can move vertically. At the same time, the sliding component on the Z-axis motion module can move vertically, thereby achieving up and down, left and right, and front and back movement. The three-dimensional motion module is a common existing structure and will not be described in detail here. The sampling rod is vertically installed on the three-dimensional motion module (the sliding component of the Z-axis motion module) and moves with the three-dimensional motion module in the up and down, left and right, and front and back planes. The vacuum suction cup is fixed downward at the bottom of the sampling rod. The vacuum suction cup is connected to the vacuum pump through an air pipe. Since the vacuum suction cup rises and falls with the sampling rod, a spring-type air pipe is used for the air pipe. The sensing and control component is also connected to the vacuum pump. The operation of the vacuum pump is controlled by the sensing and control component, thereby controlling the vacuum suction cup to suck up or put down the sample bottle, thereby realizing the taking and placing of the sample bottle. Specifically, the sampling mechanism can be provided with an air tank 35 as needed. The air tank is connected to the vacuum suction cup through an air pipe and is also connected to the sensor and control component. When the vacuum suction cup consumes a large amount of air, the sensor and control component controls the gas in the air tank to flow into the vacuum suction cup. Preferably, the vacuum pump and the air tank are both installed at the bottom of the packaging shell through a shock absorber, and a muffler is installed on the shock absorber to prevent the vibration and noise during the operation of the vacuum pump from affecting the detection performance. Preferably, the vertical movement stroke of the sampling rod is 400mm. In order to prevent the sampling rod from shaking during operation, a sliding guide block 36 is installed at the bottom of the guide rail assembly of the Z-axis motion module. The sampling rod passes through the sliding guide block and moves relative to the sliding guide block.

[0055] In this embodiment, the sensing and control assembly includes a control board, an on-off valve and a pressure sensor. The on-off valve and the pressure sensor are both installed on the air pipe between the vacuum suction cup and the vacuum pump. The on-off valve and the pressure sensor are used to control the on-off of the air pipe and monitor the pressure in the air pipe respectively. The on-off valve and the pressure sensor are both connected to the control board. The control board receives the air pressure signal from the pressure sensor and controls the on-off valve, thereby controlling the vacuum suction cup to suck up or put down the sample bottle. Figure 12As shown. When sucking the sample bottle, if the air pressure signal of the pressure sensor does not change for more than 5 seconds, that is, the vacuum suction cup does not suck the sample, the control board will determine that the sample slot position is empty, give a signal, and report an error. Specifically, a vacuum filter is also connected to the air pipe between the vacuum suction cup and the vacuum pump to filter dust in the air. Furthermore, the vacuum pump and the control board are both connected to a UPS power supply, and the vacuum pump and the control board are powered by the UPS power supply. Preferably, a vacuum pump relay is also connected between the UPS power supply and the vacuum pump, and the control board is connected to the vacuum pump relay. After all samples are added, the control board controls the vacuum pump relay to cut off the power to the vacuum pump and stop working.

[0056] The sample carrier is located between the detection mechanism and the sampling mechanism, and is provided with a sample slot for placing sample bottles; the structure of the sample carrier is as follows Figure 13 As shown, in this embodiment, a pull-out opening is provided on the shell wall of the packaging shell at the sample carrier, and the sample carrier is slidably connected to the packaging shell and enters and exits the packaging shell from the pull-out opening. Specifically, the sample carrier includes a fixed support plate 41, a sample linear slide 42, a sample tray 43 and a sample drive mechanism 44. The fixed support plate is horizontally fixed in the packaging shell, and the sample linear slide is fixed to the upper surface of the fixed support plate along the pulling direction. The sample tray is slidably connected to the sample linear slide and is opposite to the pull-out opening. The sample drive mechanism is connected between the fixed support plate and the sample tray, driving the sample tray to move along the sample linear slide, so that the sample tray automatically enters and exits the packaging shell through the pull-out opening. Sample slots for placing sample bottles are evenly arranged on the sample tray. In this embodiment, two groups of sample trays are arranged side by side, and two groups of sample linear slides are also correspondingly provided. The two groups of sample trays are respectively slidably mounted on the two groups of sample linear slides and move along the two groups of sample linear slides. Specifically, each set of sample linear slides includes two parallel sample linear slides. The two sample linear slides in each set are located at the bottom of each set of sample trays on both sides, ensuring smooth movement of the sample trays. The sides of the two sample trays near the drawer opening are connected to a first side sealing plate 45. The driving mechanism is connected to one set of sample trays and drives the sample tray to move. The other set of sample trays moves synchronously under the drive of the first side sealing plate, and the first side sealing plate seals the drawer opening from the outside. Figure 1 , avoid light and avoid the cold air blowing into the sample bottle area from leaking out, reducing the cooling efficiency. In this embodiment, the sample tray includes a bottom support plate 431 and multiple horizontal trays 432, such as Figure 14-16As shown, the horizontal trays are assembled longitudinally or transversely and placed on the bottom support plate. Each horizontal tray is provided with a row of sample slots. Multiple horizontal trays form a matrix array of sample slots for placing samples to be tested. Furthermore, the sides of the horizontal trays are corrugated. Guide locating posts 433 are fixedly provided on the bottom support plate. The horizontal trays are placed on the bottom support plate and clamped between the guide locating posts, facilitating the positioning and assembly of the horizontal trays. Preferably, the guide locating posts are distributed at both ends and in the middle of the horizontal trays.

[0057] The sample tray is assembled by horizontal trays. The size of the sample slot on the horizontal tray matches the size of the sample bottle. In actual testing, the common sample bottle sizes are 20mm or 4-7mm or other sizes. Correspondingly, the size of the sample slot on the horizontal tray is 20mm or 4-7mm or other sizes. When it is necessary to test a 20mm sample bottle, a horizontal tray with a sample slot size of 20mm (see Figure 15 ) assembled into a 20mm sample tray, see Figure 1 When the 4-7mm sample bottle needs to be tested, the horizontal tray with a sample slot size of 4-7mm (see Figure 16 ) are assembled to form a sample tray with a specification of 4-7mm. It is also possible to assemble a horizontal tray with a sample slot size of 20mm and a horizontal tray with a sample slot size of 4-7mm, so that any number of sample bottles of different sizes can be placed on the same sample tray, which is convenient for customers to load more different types of samples to be tested at one time. In this embodiment, the external shape and size of the horizontal trays of sample slots of different sizes are consistent, that is, the external shape and size of the horizontal tray of the 20mm sample slot are consistent with the external shape and size of the horizontal tray of the 4-7mm or other size sample slots, see Figure 15 and Figure 16 When a sample tray of a different size needs to be replaced, only the horizontal tray needs to be removed and installed, without having to take out the entire sample tray for replacement, thus achieving a compatible design for sample bottles of different sizes. In this embodiment, RFID tag positions 46 are provided on both end surfaces of the horizontal tray for placing RFID tags. Figure 13 After the sample bottle is placed in the sample slot on the horizontal tray, the information of the sample bottle is recorded through the RFID tag, and then the RFID tag is placed on the RFID tag position to avoid errors in the sample bottle information caused by the horizontal tray being installed upside down. In this embodiment, the sample drive mechanism includes a sample drive motor 441, a drive gear 442, a driven gear 443, a synchronous gear belt 444 and a drive block 445, as shown in FIG. Figure 17As shown, the sample drive motor and driven gear are respectively fixed to the fixed support plate at both ends of the sample linear slide. The drive gear is connected to the rotating shaft of the sample drive motor. The synchronous gear belt is horizontally sleeved on the drive gear and the driven gear and meshes with the drive gear and the driven gear. The drive block is fixedly connected to the synchronous gear belt. The sample drive motor drives the synchronous gear belt to rotate, thereby driving the drive block to move. The drive block is fixedly connected to the sample tray. In this embodiment, the cross section of the sample linear slide is an "I" shape, and the bottom of the sample tray is connected to a cross section of The sample slide is a type of sample slide that sits on the sample linear slide, so that the sample tray is slidably connected to the sample linear slide to ensure the stability of the sample tray when it is automatically pulled out.

[0058] In this embodiment, an opening 411 is provided on the fixed support plate at the sample detection port of the detection mechanism. Figure 13 The sampling mechanism draws sample bottles from the sample carrier and passes them through an opening in the fixed support plate into the detection mechanism. Two sets of sample trays are located on either side of the opening. The fixed support plate is equipped with an RFID electronic tag recognition module 9 facing the two sets of sample trays. The module uses an RFID card reader to identify the content of the RFID tags on the sample rack to determine the size of the loaded sample bottle, thereby automatically determining the operating step distance of the sampling mechanism.

[0059] The additional sample loading mechanism is installed on the sample carrier and is pulled in and out of the packaging shell, see Figure 13 The additional sample loading mechanism is provided with a sample slot for placing the emergency sample bottle 200. Specifically, the additional sample loading mechanism includes a sample box 51, a second side sealing plate 52 and an additional sample driving mechanism, such as Figure 18 As shown, the sample box is provided with at least one sample slot of different sizes. The size of the sample slot on the sample box matches the size of the emergency injection bottle. The sample box is provided with one sample slot of each different size. Since the common sizes of emergency injection bottles are 20mm and 4-7mm, the sample box in this embodiment is provided with one 20mm sample slot and one 4-7mm sample slot. In actual settings, if the emergency injection bottle is of other sizes, the sample box is provided with a corresponding sample slot of other sizes. The sample box is slidably connected to the sample carrier. The shell wall of the packaging shell is provided with a sample box inlet and outlet located at the sample box, and the sample box slides in and out of the sample box inlet and outlet; the second side sealing plate extends from the sample box inlet and outlet and is fixedly connected to the sample box. The second side sealing plate is sealed around the sample box inlet and outlet to block light and prevent cold air blowing into the area from leaking out, thereby reducing cooling efficiency. If only one sample is added at a time, the additional sample is directly placed in the additional sample loading mechanism to protect it from light; if multiple samples are added at one time, the sample can be loaded into the instrument through the additional sample loading mechanism, and then the sample can be placed on the sample tray through the sampling mechanism to protect it from light, and then the samples can be added one by one.

[0060] In this embodiment, the bottom of the emergency injection bottle is detachably fixed with an external standard source 54. Specifically, the external standard source is attached to the bottom of the emergency injection bottle. Figure 19 As shown. The bottom of the sample slot on the additional sample loading mechanism is correspondingly provided with a pit, the shape and size of the pit matching the shape and size of the external standard source. When the emergency injection bottle with the external standard source fixed is placed in the sample slot on the additional sample loading mechanism, the external standard source is located in the pit at the bottom of the sample slot. When the instrument needs to be calibrated during the detection process, the external standard source is fixed to the bottom of the clean and empty emergency injection bottle, and then added into the instrument through the additional sample loading mechanism, waiting for loading and injection. The external standard source is loaded into the detection chamber of the detection mechanism together with the emergency injection bottle, realizing the calibration operation during the instrument detection process.

[0061] Specifically, the additional sample drive mechanism includes a mounting plate 531, an electric push rod 532, an additional sample linear slide 533, and an additional sample slider 534. The mounting plate is fixed to the fixed support plate of the sample carrier, the additional sample linear slide is fixed to the upper surface of the mounting plate, and the additional sample slider is slidably mounted on the additional sample linear slide. The sample box is fixedly connected to the additional sample slider. The electric push rod is arranged along the direction in which the sample box is pulled in and out, and the fixed end of the electric push rod is fixed to the lower surface of the mounting plate. The mounting plate is provided with an elongated hole. The movable end of the electric push rod extends through the elongated hole into the upper surface of the mounting plate and connects to the sample box or the additional sample linear slide. When the electric push rod is in operation, it drives the sample box to automatically enter and exit the packaging shell. Since the sample box is provided with only two sample slots, a low-cost electric push rod is sufficient. In actual configuration, a stepper motor or servo motor can also be used. When an urgent additional sample is needed, the sample box is automatically slid out of the packaging shell by the additional sample driving mechanism, and the emergency injection bottle of the sample to be tested is placed in. Then the sample box is automatically put into the packaging shell by the additional sample driving mechanism, and the second side sealing plate is sealed around the inlet and outlet of the sample box. The sampling mechanism is controlled to first suck the emergency injection bottle on the sample box and transfer it to the detection mechanism to complete the expedited detection of the sample. Figure 20 In this embodiment, the additional sample loading mechanism is installed between the two sets of sample trays, so the sample box inlet and outlet are set on the first side sealing plate, as shown. Figure 1 .

[0062] In this embodiment, the static elimination mechanism is installed on the sample carrier at the sample inlet, specifically on one side of the opening on the fixed support plate. When each sample bottle or emergency injection bottle enters the sample inlet, the static electricity is eliminated by the static elimination mechanism. Figure 13 and Figure 20 Preferably, when the program is controlled, the sampling device sucks the sample bottle or the emergency injection bottle to the static elimination mechanism, and then stays for 3 seconds to eliminate static electricity before entering the detection room for detection. Figure 21 shown.

[0063] In this embodiment, the refrigeration mechanism includes a refrigeration component 71 and a cooling and heat-insulating component 72. The refrigeration component is installed on the rear wall of the packaging shell to cool the sample and the detection mechanism; the cooling and heat-insulating component is installed in the packaging shell around the inner wall of the sample carrier and the detection mechanism, and the refrigeration component is encapsulated in the cooling and heat-insulating component. Figure 22 As shown, the cooling loss is reduced and the cooling efficiency of the samples to be tested and the testing institutions is improved.

[0064] In this embodiment, the industrial computer includes a UPS power supply, a control and signal processing board, a sampling mechanism control module, a power module, a power socket, an air switch and an external communication interface module, a vacuum pump relay, etc. The entire machine is controlled by the industrial computer to improve the reliability of the instrument and avoid differences in system stability caused by different hardware systems. At the same time, the starting and electric operations are arranged separately to facilitate maintenance and problem troubleshooting.

Claims

1. A low-background liquid scintillation spectrometer, comprising at least a packaging shell, characterized in that: The packaging shell is equipped with: A detection mechanism, which is installed at the bottom of the packaging shell and is used to detect the sample to be tested in the sample bottle; A sampling mechanism, which is installed at the top of the packaging shell and is used to transfer the sample bottle to the detection mechanism; A sample carrier, located between the detection mechanism and the sampling mechanism, the sample carrier being provided with a sample slot for placing a sample bottle; An additional sample loading mechanism is installed on the sample carrier and is pulled in and out of the packaging shell. The additional sample loading mechanism is provided with a sample slot for placing emergency injection bottles to avoid the need to re-place the placed samples in the dark. The additional sample loading mechanism includes a sample box and a second side sealing plate. The sample box is provided with at least one sample slot of different sizes. The sample box is slidably connected to the sample carrier. A sample box inlet and outlet are provided on the shell wall of the packaging shell at the sample box. The sample box slides in and out of the sample box inlet and outlet; the second side sealing plate extends from the sample box inlet and outlet and is fixedly connected to the sample box, and the second side sealing plate is sealed around the sample box inlet and outlet.

2. The low-background liquid scintillation spectrometer according to claim 1, wherein: The bottom of the emergency injection bottle is detachably fixed with an external standard source, and the bottom of the sample slot on the additional sample loading mechanism is correspondingly provided with a pit, the shape and size of the pit match the shape and size of the external standard source. When the emergency injection bottle with the external standard source is placed in the sample slot on the additional sample loading mechanism, the external standard source is located in the pit at the bottom of the sample slot.

3. The low-background liquid scintillation spectrometer according to claim 1, wherein: The sample carrier includes a sample tray, which is assembled from multiple horizontal trays along the longitudinal or transverse direction, and each horizontal tray is provided with a row of sample slots; the size of the sample slots on the horizontal tray matches the size of the sample bottle, and the external shapes and sizes of horizontal trays with different sample slot sizes are consistent.

4. The low-background liquid scintillation spectrometer according to claim 3, wherein: The sample tray also includes a bottom support plate. The two side surfaces of the horizontal tray are corrugated. Guide positioning columns are fixedly provided on the bottom support plate. The horizontal tray is assembled and placed on the bottom support plate and clamped between the guide positioning columns.

5. The low-background liquid scintillation spectrometer according to claim 1, wherein: A draw-out opening is provided on the shell wall of the packaging shell at the location of the sample carrier, and the sample carrier is slidably connected to the packaging shell and enters and exits the packaging shell through the draw-out opening.

6. The low-background liquid scintillation spectrometer according to claim 1, wherein: The sampling mechanism includes a three-dimensional motion module, a sampling rod, a vacuum suction cup, a vacuum pump, and a sensing and control component. The three-dimensional motion module is installed at the top of the packaging shell. The sampling rod is vertically installed on the three-dimensional motion module and moves with the three-dimensional motion module in the upper, lower, left, right, front and back planes. The vacuum suction cup is fixed downward at the bottom of the sampling rod. The vacuum suction cup is connected to the vacuum pump. The sensing and control component is also connected to the vacuum pump. The vacuum pump is controlled by the sensing and control component, thereby controlling the vacuum suction cup to absorb or put down the sample bottle.

7. The low-background liquid scintillation spectrometer according to claim 1, wherein: The detection mechanism includes a detection chamber, a light shield, a lead chamber, a lead plug and a lead plug driving mechanism. A sample detection port is provided on the detection chamber, the light shield covers the outside of the detection chamber, the lead chamber is fixedly installed on the top of the detection chamber, and a sample inlet is provided on the lead chamber above the sample detection port. The lead plug closes the sample inlet on the lead chamber from the side, and the lead plug and the lead chamber are movably connected. A lead plug driving mechanism is connected between the lead plug and the lead chamber, and the lead plug is driven to open and close by the lead plug driving mechanism, thereby closing or exposing the sample inlet on the lead chamber.

8. The low-background liquid scintillation spectrometer according to claim 7, wherein: The sample carrier is provided with a static elimination mechanism at the sample inlet. When each sample bottle enters the sample inlet, static electricity is eliminated by the static elimination mechanism.

9. The low-background liquid scintillation spectrometer according to claim 1, wherein: A refrigeration component is installed on the rear wall of the packaging shell; a cooling and heat-insulating component is installed around the sample carrier and the detection mechanism in the packaging shell, and the refrigeration component is packaged in the cooling and heat-insulating component.

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