Automatic sample feeder

Abstract

The utility model discloses an automatic sample feeder which comprises a base, a first driving element, a movable seat, a motor, a sample disc, a second driving element and a plurality of sample feeding units, and an output shaft of the first driving element is connected with the movable seat; the motor is connected with the sample disc; each sample feeding unit comprises a round pipe, a rotor, a driving element, a bolt and a return spring, a bolt hole and a plurality of exhaust holes are circumferentially formed in the side wall of the round pipe, one end of the bolt is inserted into the round pipe from the bolt hole, the rotor is located in the round pipe and is connected through the bolt, one end of the return spring is connected with the bolt, and the other end of the return spring is connected with the movable seat; all the round pipes are distributed on a plurality of circles which are concentric; the second driving element is installed on the base and used for driving the plug pin to move in the direction away from the rotor, so that the rotor falls out of the circular tube under the gravity of the rotor and then enters the nuclear magnetic resonance spectrometer. The automatic sample feeder is small in size, high in sample changing speed and capable of placing a large number of samples, and the number of digits can be simply increased by increasing the number of turns.

Description

Technical Field

[0001] The utility model belongs to the field of nuclear magnetic resonance spectrometers, and more specifically, relates to an automatic sample feeder. Background Art

[0002] A nuclear magnetic resonance spectrometer is a magnetic analytical instrument that uses the differences in the nuclear properties of different elements to analyze substances. It is widely used in compound structure determination, quantitative analysis, and zoological research. Placing the sample to be tested (the sample consists of the rotor and the sample tube supported by the rotor, which contains the test liquid) into the center of the NMR spectrometer's magnet is a prerequisite for NMR measurements. Traditional NMR spectrometers rely on the operator to manually place the sample into the magnet.

[0003] To meet the needs of large-scale automated sample testing, modern NMR spectrometers often use automatic sample changers to automatically insert and remove samples from the magnet (commonly known as the sample-in and sample-out process). Automatic sample changers significantly enhance the automation level of NMR spectrometers, saving significant manpower and machine time while also reducing errors caused by human operation. They are essential for large-scale sample analysis using NMR spectrometers. For automatic sample changers, sample change speed, sample capacity, and operational reliability are key considerations for designers and users.

[0004] Traditional automatic sample changers mainly implement automatic sample change in the following ways:

[0005] 1) By setting up a robotic arm and a sample tray, the robotic arm precisely positions itself on the tray to grab a sample at a specific location and place it into the spectrometer's sample tube. This approach places high demands on the robotic arm's positioning accuracy and the reliability of its grippers. Positioning errors and loose grippers can easily lead to sample failure or sample drop. The robotic arm is typically large, requiring additional space to accommodate the specified number of samples. Furthermore, the robotic arm's movements are complex, expensive, and slow to change samples.

[0006] 2) A rotatable sample tray is provided, on which a circle of samples is placed. The tray rotates to align the sample at a specific position directly with the injection tube. A pneumatic cylinder located outside the circle of samples drives the clamping mechanism, which releases the sample, allowing it to drop into the injection tube. This method arranges the samples in a circular pattern, but to achieve a specific number of samples, the circle diameter must be increased, occupying a larger area. This wastes the space inside the circle, limiting the number of samples that can be placed.

[0007] 3) A curved chain-type sample tray is provided. The sample tray is moved to a position roughly aligned with the sample tube, and an alignment device is used to completely align the sample with the sample tube before dropping the sample into the tube. This method has poor positioning accuracy during chain movement, making it easy for the chain to misalign with the sample placement port, preventing the sample from being placed into the tube. Furthermore, the curved chain is prone to jamming, which is costly.

[0008] In addition, the above-mentioned automatic sample changing devices do not have sample detection sensors on the sample tray or inside the magnet. When the working position is occupied, the sample can only be sampled to the found empty position by searching for empty positions one by one. It is impossible to know whether there is a sample inside the magnet, which easily leads to sample conflicts. Utility Model Content

[0009] In response to the above defects or improvement needs of the prior art, the present invention provides an automatic sample feeder, which has a small size, fast sample changing speed, can hold a large number of samples, has low cost, and has high sample feeding efficiency.

[0010] To achieve the above-mentioned object, according to the present invention, an automatic sample feeder is provided, characterized in that it includes a base, a first driving element, a movable seat, a motor, a sample tray, a second driving element and a plurality of sample feeding units, wherein:

[0011] The first driving element is mounted on the base, and the output shaft of the first driving element is connected to the moving seat;

[0012] The motor is fixedly mounted on the movable base, the sample tray is rotatably mounted on the movable base, and the motor is connected to the sample tray;

[0013] Each of the sample delivery units comprises a circular tube, a rotor, a latch, and a return spring. The circular tube is vertically mounted on the sample tray, with both upper and lower ends of the circular tube open. A latch hole and a plurality of exhaust holes are circumferentially arranged on the side wall of the circular tube, and the latch hole is located below all the exhaust holes. One end of the latch is inserted into the circular tube through the latch hole. The rotor is located in the circular tube and is supported by the latch. One end of the return spring is connected to the latch and the other end is connected to the sample tray.

[0014] All circular tubes are distributed on multiple circles and these circles are concentric, and the circular tubes on each circle are evenly distributed circumferentially;

[0015] The second driving element is mounted on the base to drive the latch to move in a direction away from the rotor.

[0016] Preferably, each of the sample delivery units further comprises a push rod capable of moving upward under the drive of the second driving element, the sample tray is provided with a through hole at a position corresponding to each push rod, a boss is provided on the push rod, the lower end of the push rod passes through the through hole and the boss is received by the sample tray;

[0017] The top end of the push rod is provided with a pushing surface for pushing the latch to move.

[0018] Preferably, the latch is provided with a push rod hole, and the center of the push rod hole is vertically arranged;

[0019] The pushing surface is a conical surface that is smaller at the top and larger at the bottom.

[0020] Preferably, it further comprises an electric slip ring and an encoder, wherein the encoder is mounted on the movable base and connected to the sample tray via a transmission shaft, the round tubes are numbered in sequence, and each round tube is assigned a unique encoder angular displacement value according to the number, and the encoder is connected to the controller via a cable, the inner ring of the electric slip ring is mounted on the transmission shaft, and the outer ring of the electric slip ring is fixed to the movable base, and the inner and outer rings of the electric slip ring are respectively fixed with a number of cables that are electrically connected during rotation, the cables fixed to the inner ring of the electric slip ring are connected to the photoelectric sensor, and the cables fixed to the outer ring of the electric slip ring are connected to the controller.

[0021] Preferably, the sample tray is provided with a photoelectric sensor and a color LED indicator light at a position corresponding to each circular tube. The detection head of the photoelectric sensor on each circular tube is aligned with one of the exhaust holes to detect whether there is a rotor in the circular tube. Each photoelectric sensor is connected to the controller via the electric slip ring and a cable fixed on the electric slip ring.

[0022] The colored LED indicator light is an RGB three-color indicator light, which is used to display various colors composed of RGB.

[0023] Preferably, a horizontal slide rail is provided on the base, and the movable seat is mounted on the slide rail via a slider. A position sensor is also arranged on the base for obtaining the horizontal moving position of the movable seat or the sample tray.

[0024] Preferably, two position sensors are further included, which are respectively arranged at the top and bottom of the sampling tube to obtain the position of the rotor in the sampling tube.

[0025] Preferably, the outer wall of the rotor has a step.

[0026] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0027] 1) The present invention provides multiple circles of circular tubes, allowing samples to be placed inside the tubes. Multiple circles of samples can be installed, allowing the space of the sample tray to be fully utilized, resulting in a small volume and a significant increase in the number of samples. This solves the problem in existing structures where samples are arranged in a single circle, requiring the circle diameter to be increased, occupying a larger area, and the internal space of the circle being wasted, resulting in a small number of samples that can be placed. Furthermore, the present invention uses the movement of a latch on the circular tube to cooperate with the rotor to achieve sample feeding, solving the problem in the robotic feeding method where the robot occupies a larger space and must use additional space to place the specified number of samples. Furthermore, each of the multiple circles of circular tubes is provided with a latch that can be moved under the drive of a second drive element, and the second drive element does not affect the normal rotation of the sample tray and the circular tube, and will not cause conflict or interference.

[0028] 2) The utility model drives the movement of the latch by providing a latch and a corresponding second driving element. The latch can be reliably extended and reliably returned to its original position under the action of a return spring to reliably support the rotor, thereby solving the problems of relatively low reliability of the manipulator in the existing structure, prone to positioning errors and loose clamps, which may lead to the inability to grasp the sample or the sample being dropped.

[0029] 3) The utility model drives the sample tray to rotate by a motor, and the first driving element drives the movable seat and the sample tray on the movable seat to move, thereby realizing the precise positioning of any circular tube of the sample tray and the sample position in the circular tube, and solving the problem that the positioning accuracy is poor when the chain moves, and it is easy to be misaligned with the sample tube, thus making it impossible to place the sample into the sample tube of the nuclear magnetic resonance spectrometer.

[0030] 4) The utility model combines the movement of the movable seat and the rotation of the sample plate. Adjacent circular tubes only need to rotate at a small angle, and adjacent circles only need to move horizontally a small distance, so that rapid sample change can be achieved. It has a simple structure and low cost, and solves the problems of complex manipulator movements and the high cost of the manipulator and chain.

[0031] 5) The utility model sets a photoelectric sensor at each circular tube of the sample tray and a position sensor at the bottom and top of the sample injection tube. The sample feeder knows the presence or absence of samples at all positions at any time, and uses this information to realize the functions of rapid query of empty positions, taking out samples first when there are samples in the sample injection tube of the nuclear magnetic resonance spectrometer to prevent sample conflicts, etc. This solves the problem that the sample tray and the sample injection tube of the traditional sample feeder are not equipped with sample detection sensors, and when the working position is occupied, the sample can only be sampled to the found empty position by searching for empty positions one by one, and it is impossible to know whether there are samples inside the sample injection tube, which easily leads to sample conflicts. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1This is a three-dimensional schematic diagram of an automatic sample feeder of the utility model;

[0033] Figure 2 This is a schematic diagram of the assembly of a sample tray and a movable seat of an automatic sample feeder of the utility model;

[0034] Figure 3 It is a cross-sectional view of the sample tray and mobile seat assembly diagram;

[0035] Figure 4 This is a schematic diagram of the alignment of a round tube and a sample feeding tube on an automatic sample feeder of the present invention;

[0036] Figure 5 is a schematic diagram of a pin-supported sample on a circular tube;

[0037] Figure 6 This is a schematic diagram of the encoder connected to the electric slip ring in the utility model;

[0038] Figure 7 This is a schematic diagram of the base;

[0039] Figure 8 This is a schematic diagram of an automatic sample feeder of the utility model installed on a nuclear magnetic resonance spectrometer;

[0040] Figure 9 The utility model is a flow chart of a sample feeding method of an automatic sample feeder. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0042] Reference Figures 1 to 7 , an automatic sample feeder, including a base 711, a first driving element 706, a moving seat 44, a motor 311, a sample tray 21, a second driving element 703 and a plurality of sample feeding units.

[0043] The first driving element 706 is installed on the base 711, and the output shaft of the first driving element 706 is connected to the movable seat 44 to drive the movable seat 44 to move horizontally; the base 711 of the utility model is used to install the sample feeder to the magnet 81 of the nuclear magnetic resonance spectrometer as a basis for installing other parts.

[0044] The motor 311 is fixedly mounted on the movable base 44 , and the sample tray 21 is rotatably mounted on the movable base 44 . The movable base 44 drives the sample tray 21 to move horizontally, and the motor 311 is connected to the sample tray 21 to drive the sample tray 21 to rotate. As a preferred embodiment, a horizontal slide rail 705 is provided on the base 711, and the movable seat 44 is mounted on the slide rail 705 via a slider 308. A position sensor 710 is also arranged on the base 711 for obtaining the horizontal position of the movable seat 44 or the sample tray 21, so as to facilitate the first driving element 706 to control the movable seat 44 to move horizontally and then stop at the set position. Preferably, there are two position sensors 710 on the base 711, one position sensor 710 for obtaining the position where the inner circle of the sample tray 21 is aligned with the injection tube 42 after the movable seat 44 moves horizontally to the left, and one position sensor 710 for obtaining the position where the outer circle of the sample tray 21 is aligned with the injection tube 42 after the movable seat moves horizontally to the right, thereby facilitating the first driving element 706 to control the movable seat 44 to stop after horizontal movement. When the sample tray 21 is set to have more turns, the number of position sensors 710 is increased accordingly, and corresponds to the position where each turn of the sample tray 21 is aligned with the injection tube 42 after the movable seat 44 moves horizontally.

[0045] Each sample delivery unit includes a circular tube 303, a rotor 51, a push rod 701, a latch 56, and a return spring 55. The circular tube 303 is vertically mounted on the sample tray 21. Both the upper and lower ends of the circular tube 303 are open. A latch hole 53 and multiple vent holes 301 are circumferentially provided on the sidewall of the circular tube 303. The latch hole 53 is located below all of the vent holes 301. One end of the latch 56 is inserted into the circular tube 303 through the latch hole 53. The rotor 51 is located within the circular tube 303 and supported by the latch 56. One end of the return spring 55 is connected to the latch 56 and the other end is connected to the sample tray 21. This allows the latch 56, which has exited the inner hole of the circular tube 303, to move toward the rotor 51 to catch a fallen rotor 51. All latch holes 53 and vent holes 301 are located above the sample tray 21, thereby being exposed.

[0046] All circular tubes 303 are distributed on multiple concentric circles, with the circular tubes 303 on each circle evenly distributed circumferentially. The circular tubes 303 on the sample tray 21 of the present invention are preferably divided into two circles, with the circular tubes 303 on each circle evenly distributed circumferentially. Each circular tube 303 is provided with a circle of exhaust holes 301 at its upper end. In the present invention, six exhaust holes 301 of equal size and evenly spaced are preferably provided on the upper end of the circular tube 303, with a latch hole 53 provided below each of the exhaust holes 301. If compressed air is used to propel the rotor 51 upward, the exhaust holes 301 can be vented after the rotor 51 moves upward beyond the height of the exhaust holes 301, preventing the rotor 51 from moving too far upward and bursting out of the circular tube 303.

[0047] The second drive element 703 is mounted on the base 711 and is used to drive the latch 56 away from the rotor 51, so that the rotor 51 falls out of the tube 303 under its own weight and enters the sample inlet 42 of the nuclear magnetic resonance spectrometer. The second drive element 703 can directly drive the latch 56 to move, or it can indirectly drive the latch 56 to move through an intermediate component.

[0048] The base 711 has a support plate 708, on which a slide rail 705, a positioning block 707, a first driving element 706 and two position sensors 710 are fixed. The slide rail 705 is connected to the slider 308 on the movable seat 44, and the positioning block 707 limits the moving stroke of the slider 308, thereby limiting the sample tray 21.

[0049] The motor 311 is preferably connected to the sample tray 21 via a bevel gear mechanism. The motor 311 is preferably a DC motor 311. The sample tray 21 is preferably mounted on the movable base 44 via a cross roller bearing 65. The movable base 44 includes a sample tray support base 309, a connecting block 46, and a motor bracket 45, which are fixedly connected together. The motor 311 is mounted on the motor bracket 45. The first drive element 706 is mounted below the support plate 708. The coupling plate fixed to the output shaft of the first drive element 706 is fixedly connected to the connecting block 46. The output shaft of the first drive element 706 can be telescopically moved to drive the movable base 44 and the sample tray 21 thereon to move horizontally.

[0050] Furthermore, the present invention includes an electric slip ring 61 and an encoder 64. The encoder 64 is mounted on the movable base 44 and connected to the sample tray 21 via a drive shaft 62 for measuring the angular displacement of the sample tray 21. The circular tubes 303 are sequentially numbered, each assigned a unique encoder angular displacement value. The encoder 64 is connected to a controller via a cable. The inner ring of the electric slip ring 61 is fixedly mounted on the drive shaft 62, and the outer ring of the electric slip ring 61 is fixed to the movable base 44. The inner and outer rings of the electric slip ring 61 each have a plurality of cables fixed to them, which are electrically connected during rotation. The cables on the inner ring of the electric slip ring are connected to the photoelectric sensor 710, and the cables on the outer ring of the electric slip ring are connected to the controller.

[0051] The bevel gear mechanism includes a first bevel gear 306 and a second bevel gear 310 that mesh with each other. The bottom of the sample tray 21 is fixed to the upper end of the outer ring of the cross roller bearing 65. The lower end of the outer ring of the cross roller bearing 65 is fixed to the first bevel gear 306. The rotation of the first bevel gear 306 drives the sample tray 21 to rotate. The lower end of the inner ring of the cross roller bearing 65 is fixedly mounted on a hollow sample tray support 309. The other end of the sample tray support 309 is fixed to the movable base 44. The movable base 44 is mounted on a motor bracket 45. A motor 311 is fixed to the motor bracket 45. The second bevel gear 310 is mounted on the output shaft of the motor 311, meshing with the first bevel gear 306. Two sets of parallel sliders 308 are installed under the movable base 44, and a positioning baffle 43 is installed on the side of the sample tray 21; the movable base 44 also includes an encoder base 63, which is fixed to the upper end of the inner ring of the cross roller bearing 65, and an encoder 64 is installed in the encoder base 63; the rotating shaft of the encoder 64 is connected to one end of the transmission shaft 62, and the other end of the transmission shaft 62 is connected to the sample tray 21; the inner ring of the electric slip ring 61 is installed on the transmission shaft 62, and the outer ring of the electric slip ring 61 is positioned at an angle using screws installed on the encoder base 63 to prevent the outer ring of the electric slip ring 61 from rotating.

[0052] The output shaft of the second drive element 703 can drive the horizontal movement of the latch 56 using a variety of existing methods. For example, the latch 56 can be driven horizontally by an intermediate component, such as a rotatable lever or a connecting rod and slider mechanism. Alternatively, the output shaft of the second drive element 703 can be directed vertically downward, with the inclined surface of the intermediate component interfacing with the structure of the latch 56 to achieve horizontal movement. However, the intermediate component must be promptly removed from the rotation area of ​​the circular tube 303 to prevent interference with the normal rotation of the circular tube 303 on the sample tray 21.

[0053] As a preferred solution of the present invention, each of the sample delivery units also includes a push rod 52 that can move upward under the drive of the second driving element 703, and the sample tray 21 is respectively provided with a through hole at a position corresponding to each push rod 52, and a boss is provided on the push rod 52, and the lower end of the push rod 52 passes through the through hole and the boss is supported by the movable seat 44.

[0054] A pushing surface 57 is provided at the top end of the push rod 52 . The pushing surface 57 is used to push the latch 56 to move away from the rotor 51 when the push rod 52 moves upward.

[0055] A drive element holder 702 is fixedly mounted on the output shaft of the second drive element 703. A push rod 701 and a guide rod 704 are respectively mounted on the drive element holder 702. The guide rod 704 is movably mounted on the movable seat 44. The push rod 701 can move upward to contact the bottom end of the push rod 52, thereby pushing the push rod 52 upward. Driven by the second drive element 703, the push rod 701 moves downward and separates from the bottom end of the push rod 52. The push rod 52 falls under its own weight and is received by the movable seat 44. The latch 56 can then be moved back and forth toward the rotor 51 under the action of the return spring 55. A boss provided on the push rod 52 facilitates the reception of the push rod 52 by the movable seat 44. Therefore, only one second drive element 703 is required. After each sample delivery unit rotates to a position corresponding to the second drive element 703, the second drive element 703 can drive the push rod 52 upward, causing the latch 56 to move horizontally away from the rotor 51.

[0056] The latch 56 is provided with a push rod hole 54, the center of which is vertically arranged; the pushing surface 57 is a conical surface that is smaller at the top and larger at the bottom, so that it can extend into the push rod hole 54 and contact the edge of the hole of the push rod 54 to push the latch 56 to move away from the rotor 51. When the sample delivery unit is not delivering samples, the return spring 55 causes the latch 56 to extend into the interior of the circular tube 303 to support the rotor 51 containing the sample tube. At this time, the push rod hole 54 deviates from the center line of the conical surface of the push rod 52 below. When it is the turn of the sample delivery unit to deliver samples, the push rod 52 is introduced into the push rod hole 54, forcing the push rod hole 54 to align with the central axis of the push rod 52. The latch 56 withdraws from the interior of the circular tube 303, causing the rotor 51 containing the sample to lose support. The rotor 51 will fall downward under the action of its own weight. Regardless of whether a sample is being delivered or not, the ejector pin 7 is always extended into the ejector pin hole 54, with the center line of the conical surface being aligned or not aligned with the center of the ejector pin hole 54, and the pushing surface is always in contact with the edge of the ejector pin hole 54 to prevent the latch 56 from rotating and causing the ejector pin hole 54 to deviate from the ejector pin 52.

[0057] Furthermore, the sample tray 21 is provided with a photoelectric sensor 710 and a color LED indicator 22 at a position corresponding to each circular tube 303. The detection head of the photoelectric sensor 710 on each circular tube 303 is aligned with one of the exhaust holes 301 to detect whether there is a rotor 51 in the circular tube 303. Each photoelectric sensor 710 is connected to the controller via the electric slip ring 61.

[0058] The colored LED indicator light 22 is an RGB three-color indicator light, which can display various colors composed of RGB, and:

[0059] When the photoelectric sensor 710 detects that there is no rotor 51 in the round tube 303 and the round tube 303 is in the non-working position, the color LED indicator 22 is displayed in green;

[0060] When the round tube 303 is in the working position, the color LED indicator 22 is displayed in red;

[0061] When the photoelectric sensor 710 detects that the rotor 51 is in the circular tube 303 and the circular tube 303 is in the non-working position, then: if the rotor 51 has not yet entered the nuclear magnetic resonance spectrometer for detection, the color LED indicator 22 will be displayed in blue; if the rotor 51 has entered the nuclear magnetic resonance spectrometer, completed the detection, and exited from the nuclear magnetic resonance spectrometer into the circular tube 303, the color LED indicator 22 will be displayed in green;

[0062] The position of the circular tube 303 on the sample tray 21 that is aligned with the sample inlet tube 42 of the nuclear magnetic resonance spectrometer is the working position of the circular tube 303 , and the other positions of the circular tube 303 on the sample tray 21 are the non-working positions of the circular tube 303 .

[0063] Furthermore, two position sensors are provided at the top and bottom of the sampling tube 42 , respectively, for obtaining the position of the rotor 51 in the sampling tube 42 , and assisting in confirming whether the rotor 51 has entered the sampling tube 42 or has left the sampling tube 42 .

[0064] The outer wall of the rotor 51 has a step to allow compressed gas to enter the sample tube 42 and blow upward onto the step of the rotor 51, thereby applying an upward thrust to the rotor 51, causing it to float out of the sample tube and into the circular tube 303 aligned with the sample tube. When the rotor 51 rises to a height above the step above the exhaust hole 301, the compressed gas that has pushed the rotor 51 upward is discharged through the exhaust hole 301, causing the rotor 51 to remain at the position corresponding to the exhaust hole 301. The airflow acts on the step of the outer wall of the rotor 51 and not on the sample tube held by the rotor 51, so that the sample tube is prevented from being pushed upward out of the rotor 51 during the blowing.

[0065] Reference Figure 8According to another aspect of the present invention, a sample feeding method of the automatic sample feeder is provided, comprising the following steps:

[0066] S1, the controller receives the number of the circular tube 303 that needs to be sent to the nuclear magnetic resonance spectrometer in the non-working position, and reads the detection situation (detection status) of the photoelectric sensor 710 on the circular tube 303 that needs to be sent to the non-working position, and determines whether there is a rotor in the circular tube 303 in the non-working position. If the photoelectric sensor 710 detects that there is a rotor 51 in the circular tube 303 that needs to be sent to the non-working position, the controller enters step S2 to send the rotor 51 in the circular tube 303 into the sample injection tube 42 of the nuclear magnetic resonance spectrometer. If the photoelectric sensor 710 detects that there is no rotor 51 in the circular tube 303 that needs to be sent to the sample, the controller reports an error and ends; wherein, the position of the circular tube 303 on the sample tray 21 that is aligned with the sample injection tube 42 of the nuclear magnetic resonance spectrometer is the working position of the circular tube 303, and the other positions of the circular tube 303 on the sample tray 21 are the non-working positions of the circular tube 303;

[0067] S2. The controller reads detection signals from the position sensor at the bottom and the position sensor at the top of the sampling tube 42 of the nuclear magnetic resonance spectrometer to detect whether there is a rotor 51 at the bottom of the sampling tube 42. If the rotor 51 is detected at the bottom of the sampling tube 42, the rotor 51 at the bottom of the sampling tube 42 is first sent into the circular tube 303 at the working position and supported by the latch 56. A driving device can be set in the nuclear magnetic resonance spectrometer to drive the rotor 51 to move vertically upward into the circular tube 303 at the working position.

[0068] If it is detected that there is no rotor 51 at the bottom of the injection tube 42, the process proceeds to step S3;

[0069] S3. The controller controls the horizontal position of the movable base 44 and the rotation angle of the sample tray 21 to move the round tube 303 that needs to be sampled and is located in the non-working position in step S1 to the working position. This can be achieved by rotating the motor 311 and / or extending the first driving element 706.

[0070] S4. The controller opens the air valve of the nuclear magnetic resonance spectrometer. The air flows through the sample inlet tube 42 and enters the circular tube 303 at the working position. The airflow exerts an upward thrust on the rotor 51 in the circular tube 303, causing the rotor 51 to float upward, thereby separating the rotor 51 from the latch 56 and facilitating the latch 56 to move away from the rotor 51.

[0071] S5. The controller controls the second driving element 703 to drive the latch 56 to move horizontally, so that the latch 56 moves away from the rotor 51.

[0072] S6, the controller controls the gas valve of the nuclear magnetic resonance spectrometer to gradually reduce the gas output, and the rotor 51 enters the sample injection tube 42 under the action of its own weight;

[0073] S7. Detect the detection signals of the position sensor at the top of the sampling tube 42 and the position sensor at the bottom of the sampling tube 42 to determine whether the rotor 51 has successfully reached the bottom of the sampling tube 42. If successful, the process ends. If unsuccessful, steps 4 to 7 are repeated in a loop (opening and closing the air valve multiple times) until the rotor 51 successfully reaches the bottom of the sampling tube 42.

[0074] As a preferred solution, the present invention uses air blowing to move the rotor 51 at the bottom of the sample injection tube 42 into the circular tube 303 at the working position. In step S2, the specific steps of moving the rotor 51 at the bottom of the sample injection tube 42 into the circular tube 303 at the working position and supporting it through the latch 56 are as follows:

[0075] S2.1. Determine whether there is a rotor 51 in the circular tube 303 at the working position. If there is no rotor 51 in the circular tube 303 at the working position, proceed to S2.2. If there is a rotor 51 in the circular tube 303 at the working position, proceed to S2.3.

[0076] S2.2. This step specifically includes the following sub-steps:

[0077] S2.2.1. The second driving element 703 drives the latch 56 to move horizontally, causing the latch 56 to move away from the rotor 51;

[0078] S2.2.2. The controller opens the air valve on the NMR spectrometer. The airflow from the air valve enters the sampling tube 42 and blows upward, pushing the rotor 51 in the sampling tube 42 to float into the circular tube 303 at the working position.

[0079] S2.2.3. The controller reads the position sensor at the bottom of the sample injection tube 42, the position sensor at the top of the sample injection tube 42, and the photoelectric sensor 710 on the circular tube 303 at the working position, and determines whether the rotor 51 has reached the top of the circular tube 303 at the working position.

[0080] If the photoelectric sensor 710 detects that the rotor 51 has arrived, the second driving element 703 moves so that the latch 56 returns to its original position under the action of the return spring 55, and the latch 56 is inserted into the round tube 303. Then, the air valve is closed, and the rotor 51 falls and is supported and fixed in the round tube by the latch 56.

[0081] If the photoelectric sensor 710 detects that the rotor 51 has not arrived, the air valve is closed and opened cyclically to allow the airflow to push the rotor 51 upward until the rotor 51 reaches the top of the circular tube 303 at the working position. The second driving element 703 moves so that the latch 56 returns to its original position under the action of the return spring 55 and is inserted into the circular tube 303. Then the air valve is closed, and the rotor 51 falls and is supported and fixed in the circular tube by the latch 56.

[0082] S2.3 includes the following sub-steps:

[0083] S2.3.1. Read the detection signal of the photoelectric sensor 710 corresponding to each tube 303 on the sample tray 21, and find the tube 303 number N that is closest to the working position and has no rotor 51 in it. 空 ;

[0084] S2.3.2. Move the round tube 303 found in step S2.3.1 to the working position;

[0085] S2.3.3. Perform the above step S2.2 to move the rotor 51 at the bottom of the sample injection tube 42 into the circular tube 303 that has moved to the working position in step S2.2.2.

[0086] The first drive element 706 can be a pneumatic cylinder, hydraulic cylinder, electric cylinder, or electric push rod, and the second drive element 703 can be a pneumatic cylinder, hydraulic cylinder, electric cylinder, or electric push rod. When the sample tray 21 has two circles of circular tubes 303, the positioning blocks 707 correspond to the extreme horizontal movement positions of the outer and inner circles of the circular tubes 303, respectively. When there are more than two circles of circular tubes 303, the positioning blocks 707 correspond to the extreme horizontal movement positions of the outermost and innermost circles, respectively. When there are more than two circles of circular tubes 303, the first drive element 706 is an electric cylinder equipped with an encoder 64 for precisely controlling the movement position of the movable base 44.

[0087] Reference Figure 2 、 Figure 4 and Figure 7After the automatic sample feeder of the present invention is installed on the nuclear magnetic resonance spectrometer 81, the coupling plate on the output shaft of the second drive element 703 extends, pushing the movable base 44 horizontally to the right, thereby also shifting the sample tray 21 to the right. The positioning block 707 on the right side of the base limits the slider 308, ensuring that the center of the nozzle of the sample tube 42 is aligned with the center of one of the circular tubes 303 on the outer ring of the sample tray 21. At this time, the circular tube 303 is in the working position. The output shaft of the motor 311 rotates, sequentially driving the second bevel gear 310, the first bevel gear 306, and the sample tray 21. The rotation of the sample tray 21 drives the transmission shaft 62, which in turn drives the inner ring of the electric slip ring 61 and the rotating shaft of the encoder 64. The encoder 64 detects the angle of the sample tray 21 in real time and feeds it back to the control system. The controller then corrects the position error, achieving closed-loop control of the entire system and ensuring the accuracy of the alignment of the circular tube 303 with the sample tube 42. When the circular tube 303 is precisely aligned with the sample injection tube 42, the output shaft of the second driving element 703 extends, pushing the driving element fixing seat 702 and the push rod 701 upward in turn. The guide rod 704 prevents the push rod 701 from angular deflection during the up and down movement. The push rod 701 moves upward to push the push rod 52 to move upward and insert it into the push rod hole 54, forcing the latch 56 to move right. The latch 56 completely withdraws from the inner cavity of the circular tube 303 and shrinks into the latch hole 53 of the circular tube 303. The rotor 51 loses its support and, under the action of the airflow from the air valve of the nuclear magnetic resonance spectrometer (the air valve is connected to the compressed air tank), gradually and slowly falls from the circular tube 303 into the sample injection tube 42. After the nuclear magnetic resonance test is completed, the rotor 51 is under the action of the airflow from the air valve It rises to the top of the circular tube 303, and the photoelectric sensor 710 detects whether there is a rotor 51 in the circular tube 303 at the working position through the exhaust hole 301. If not, the sample continues to be discharged. If so, the output shaft of the second driving element 703 retracts, driving the driving element fixing seat and the push rod 701 to move downward in turn. The push rod 52 falls under the action of its own gravity, and the latch 56 returns to its original position under the action of the return spring 55, and is inserted into the interior of the circular tube 303 along the latch hole 53 to support the rotor 51, completing the sampling and discharging process of a sample (the sample includes the rotor 51 and the sample tube installed on the rotor 51, and the sample tube contains the test liquid). The motor 311 drives the sample tray 21 to rotate and completes the sampling and discharging of the next sample according to the above process.

[0088] After the analysis of the samples in the outer circle of the sample tray 21 is completed, the connecting plate of the first driving element 706 retracts, pushing the sample tray 21 to the left, and the positioning block 707 on the left limits the slider 308 to ensure that the center of the tube mouth of the sampling tube 42 is aligned with the circle where the center of one of the circular tubes 303 in the inner circle of the sample tray 21 is located. The motor 311 drives the sample tray 21 to rotate, and the analysis of the samples in each circular tube 303 in the inner circle of the sample tray 21 is completed according to the above process.

[0089] It will be easily understood by those skilled in the art that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An automatic sample feeder, characterized in that: It includes a base, a first driving element, a moving seat, a motor, a sample tray, a second driving element and a plurality of sample delivery units, wherein: The first driving element is mounted on the base, and the output shaft of the first driving element is connected to the moving seat; The motor is fixedly mounted on the movable base, the sample tray is rotatably mounted on the movable base, and the motor is connected to the sample tray; Each of the sample delivery units comprises a circular tube, a rotor, a latch, and a return spring. The circular tube is vertically mounted on the sample tray, with both upper and lower ends of the circular tube open. A latch hole and a plurality of exhaust holes are circumferentially arranged on the side wall of the circular tube, and the latch hole is located below all the exhaust holes. One end of the latch is inserted into the circular tube through the latch hole. The rotor is located in the circular tube and is supported by the latch. One end of the return spring is connected to the latch and the other end is connected to the sample tray. All circular tubes are distributed on multiple circles and these circles are concentric, and the circular tubes on each circle are evenly distributed circumferentially; The second driving element is mounted on the base to drive the latch to move in a direction away from the rotor.

2. The automatic sample feeder according to claim 1, characterized in that: Each of the sample delivery units further comprises a push rod capable of moving upward under the drive of the second driving element, the sample tray is provided with a through hole at a position corresponding to each push rod, a boss is provided on the push rod, a lower end of the push rod passes through the through hole and the boss is received by the sample tray; The top end of the push rod is provided with a pushing surface for pushing the latch to move.

3. The automatic sample feeder according to claim 2, characterized in that: The latch is provided with a push rod hole, and the center of the push rod hole is vertically arranged; The pushing surface is a conical surface that is smaller at the top and larger at the bottom.

4. The automatic sample feeder according to claim 1, characterized in that: It also includes an electric slip ring and an encoder, the encoder is installed on the movable base, and the encoder is connected to the sample plate through a transmission shaft. The round tubes are numbered in sequence, and each round tube is assigned a unique encoder angular displacement value according to the number. The encoder is connected to the controller through a cable, the inner ring of the electric slip ring is installed on the transmission shaft, and the outer ring of the electric slip ring is fixed to the movable base. The inner and outer rings of the electric slip ring are respectively fixed with a number of cables that are electrically connected when rotating. The cables fixed to the inner ring of the electric slip ring are connected to the photoelectric sensor, and the cables fixed to the outer ring of the electric slip ring are connected to the controller.

5. The automatic sample feeder according to claim 4, characterized in that: The sample tray is provided with a photoelectric sensor and a color LED indicator light at a position corresponding to each round tube. The detection head of the photoelectric sensor on each round tube is aligned with one of the exhaust holes to detect whether there is a rotor in the round tube. Each photoelectric sensor is connected to the controller via the electric slip ring and a cable fixed on the electric slip ring. The colored LED indicator light is an RGB three-color indicator light, which is used to display various colors composed of RGB.

6. The automatic sample feeder according to claim 1, characterized in that: The base is provided with a horizontal slide rail, and the movable seat is mounted on the slide rail via a slider. A position sensor is also arranged on the base for obtaining the horizontal moving position of the movable seat or the sample tray.

7. The automatic sample feeder according to claim 1, characterized in that: The invention also comprises two position sensors which are respectively arranged at the top and the bottom of the sampling tube so as to obtain the position of the rotor in the sampling tube.

8. The automatic sample feeder according to claim 1, characterized in that: An outer wall of the rotor has a step.

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