COD (Chemical Oxygen Demand) analyzer adaptive to digestion cups with different diameters

Abstract

The utility model discloses a chemical oxygen demand (COD) analyzer adaptable to digestion cups with different diameters, which relates to the technical field of chemical experiment instruments and comprises an instrument framework, a support plate and a heating plate. A pressing mechanism is arranged on the instrument framework; a first through hole is formed in the supporting plate; a separating mechanism is arranged at the lower part of the supporting plate and comprises a limiting plate; a second through hole is formed in the limiting plate; and a variable-diameter limiting mechanism is arranged on the limiting plate and located at the second through hole. The variable-diameter limiting mechanism is mounted on the limiting plate of the separation mechanism, so that the instrument can be adaptive to the digestion cups with different diameters in a certain size range; meanwhile, the reducing limiting mechanism can fix the digestion cup in the second through hole in the limiting plate to limit the radial displacement of the digestion cup, so that the digestion cup is centered (the central axis of the digestion cup and the central axis of the second through hole are collinear). Therefore, the digestion cup is always kept in a vertical state and is better attached to the heating plate under the downward pressing force of the downward pressing mechanism.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical experimental instruments, in particular to a COD analyzer adaptable to digestion cups of different diameters. Background Art

[0002] Chemical oxygen demand (CODCr) by dichromate method, or CODCr for short, measures the amount of reducing substances in water that need to be oxidized and is a key indicator of water pollution. High CODCr levels in water indicate severe organic contamination. Therefore, it is a crucial parameter in fields such as environmental monitoring and wastewater treatment. The reference national standard for this method is "Determination of Chemical Oxygen Demand in Water - Dichromate Method" (HJ828-2017).

[0003] When analyzing a water sample, one of the processing steps is heating the sample. In the prior art, this heating method is generally used as follows: the sample water is first poured into a digestion sample cup, which is then placed on a heating plate for heating. During this process, a clamping mechanism is required to secure the digestion sample cup, ensuring its stability during heating, and then heating the liquid within.

[0004] The aforementioned method for analyzing water samples presents the following problem: the digestion sample cups vary in size, particularly in diameter. Conventional techniques typically employ a fixture of a fixed size to accommodate the digestion sample cup. If the diameter of the digestion sample cup does not match the fixture, the clamping effect is poor, hindering the smooth progress of the experiment.

[0005] Therefore, a COD analyzer that can adapt to digestion cups of different diameters is proposed. Utility Model Content

[0006] The purpose of the utility model is to overcome the deficiencies of the prior art and provide a COD analyzer that can be adapted to digestion cups of different diameters.

[0007] The purpose of this utility model is achieved through the following technical solutions:

[0008] A COD analyzer that can adapt to digestion cups of different diameters, includes an instrument frame, on which a support plate and a heating plate are arranged at intervals from top to bottom; a limit ring is provided on the cup body of the digestion cup near its own opening; a downward pressing mechanism is provided on the instrument frame, which makes the bottom of the digestion cup fit against the heating plate during heating; a first through hole adapted to the limit ring is provided on the support plate; a disengagement mechanism adapted to the digestion cup is provided at the lower part of the support plate, and the disengagement mechanism includes a limit plate connected to the support plate; a second through hole adapted to the digestion cup is provided on the limit plate, and the central axis of the second through hole is collinear with the central axis of the first through hole; a diameter-changing limit mechanism is provided on the limit plate at the second through hole.

[0009] Furthermore, in the present invention, the above-mentioned disengagement mechanism also includes a guide shaft connected to the above-mentioned support plate, and a support plate and a spring sequentially arranged on the above-mentioned guide shaft from top to bottom, and the central axis of the above-mentioned guide shaft is parallel to the central axis of the above-mentioned first through hole; the above-mentioned support plate is slidably connected to the above-mentioned guide shaft and is located below the above-mentioned support plate; the above-mentioned limit plate is connected to the above-mentioned guide shaft, and is located below the above-mentioned support plate; one end of the above-mentioned spring is connected to the above-mentioned support plate, and the other end is connected to the above-mentioned limit plate; a third through hole with a diameter smaller than the diameter of the above-mentioned limit ring is provided on the above-mentioned support plate, and the diameter of the above-mentioned third through hole is greater than or equal to the outer diameter of the above-mentioned digestion cup; the central axis of the above-mentioned third through hole is collinear with the central axis of the above-mentioned first through hole.

[0010] Furthermore, in the present invention, the variable diameter limiting mechanism includes at least two groups of limiting units, and the two groups of limiting units are distributed at the edge of the second through hole in a circular array.

[0011] Furthermore, in the present invention, any of the above-mentioned limit units includes a frame body arranged at the edge of the above-mentioned second through hole, and an upper limit shaft and a lower limit shaft arranged on the above-mentioned frame body from top to bottom, and the above-mentioned upper limit shaft is rotatably connected to the limit bar and the torsion spring; the upper end of the above-mentioned torsion spring is connected to the upper end portion of the above-mentioned limit bar, and the lower end thereof abuts against the above-mentioned lower limit shaft; the part of the above-mentioned limit bar located below the above-mentioned upper limit shaft is located between the above-mentioned lower limit shaft and the central axis of the above-mentioned second through hole.

[0012] Furthermore, in the present invention, a side of the limit strip away from the central axis of the second through hole is provided with an avoidance groove adapted to the lower limit axis, and the opening of the avoidance groove faces the lower limit axis.

[0013] Furthermore, in the present invention, the above-mentioned downward pressure mechanism includes a lifting mechanism arranged on the above-mentioned instrument frame, a mounting plate connected to the execution end of the above-mentioned lifting mechanism, and a condenser arranged on the above-mentioned mounting plate; the central axis of the above-mentioned condenser is collinear with the central axis of the above-mentioned first through hole.

[0014] Furthermore, in the present invention, a liquid adding mechanism is further provided on the instrument frame, and the liquid adding mechanism includes an upper liquid adding mechanism for adding liquid into the condenser tube and a lower liquid adding mechanism for adding liquid into the digestion cup.

[0015] Furthermore, in the present invention, the upper liquid adding mechanism includes a first liquid adding arm that can move linearly and rotate, and the first liquid adding arm is provided with a first liquid adding port.

[0016] Furthermore, in the present invention, the lower liquid adding mechanism includes a second liquid adding arm that can move linearly and rotate, and a second liquid adding port is provided on the second liquid adding arm.

[0017] The beneficial effects of the utility model are:

[0018] The utility model provides a COD analyzer that can adapt to digestion cups of different diameters. By installing a variable diameter limiting mechanism on the limiting plate of the disengagement mechanism, the instrument can adapt to digestion cups of different diameters within a certain size range. At the same time, the variable diameter limiting mechanism can fix the digestion cup in the second through hole of the limiting plate, limiting its radial displacement and aligning it (making the central axis of the digestion cup and the central axis of the second through hole collinear). In this way, the digestion cup always remains in a vertical state and can fully fit on the heating plate under the downward pressure of the downward pressure mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic structural diagram of an embodiment of the present utility model;

[0020] Figure 2 for Figure 1 Left view of;

[0021] Figure 3 This is a schematic diagram of the installation of the variable diameter limiting mechanism of the embodiment of the utility model;

[0022] Figure 4 This is a cross-sectional view of a variable diameter limiting mechanism according to an embodiment of the present utility model;

[0023] Figure 5 This is a structural diagram of a digestion cup installed in a variable diameter limiting mechanism according to an embodiment of the utility model;

[0024] Figure 6 for Figure 2 A partial enlarged view of point A in the middle;

[0025] Figure 7 for Figure 2 A partial enlarged view of point B in the middle.

[0026] In the figure: 101-instrument skeleton; 201-support plate; 301-heating plate; 401-digestion cup; 4011-limiting ring; 501-limiting plate; 5011-second through hole; 502-guide shaft; 503-support plate; 504-spring; 601-frame; 602-upper limit shaft; 603-lower limit shaft; 604-limiting bar; 6041-avoidance groove; 605-torsion spring; 701-lifting mechanism; 702-mounting plate; 703-condenser; 801-first liquid adding arm; 901-second liquid adding arm; 1001-cantilever; 1002-motor; 1003-turntable; 1004-first magnet; 1005-second magnet; 1101-camera; 1102-color sensor. DETAILED DESCRIPTION

[0027] The following will be combined with the embodiments to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work shall fall within the scope of protection of the present invention.

[0028] See also Figure 1-7 , the utility model provides a technical solution:

[0029] A COD analyzer adaptable to digestion cups of different diameters comprises an instrument frame 101, on which a support plate 201 and a heating plate 301 are arranged spaced apart from each other from top to bottom, the support plate 201 and the heating plate 301 being parallel to each other; a limit ring 4011 is installed on the body of the digestion cup 401 near its opening; a downward pressing mechanism is provided on the instrument frame 101, which causes the bottom of the digestion cup 401 to fit against the heating plate 301 during heating; a first through hole is provided on the support plate 201 that is adapted to the limit ring 4011; and a detachment mechanism adapted to the digestion cup 401 is provided at the lower portion of the support plate 201. The detachment mechanism, on the one hand, fixes the digestion cup 401 on the support plate 201; on the other hand, when the heating plate 301 has finished heating the liquid in the digestion cup 401, the detachment mechanism can move the digestion cup 401 away from the heat source "heating plate 301", thereby accelerating the cooling of the liquid in the digestion cup 401.

[0030] The disengagement mechanism includes a stopper plate 501 connected to the support plate 201. A second through-hole 5011 is defined on the stopper plate 501, which is adapted to fit the digestion cup 401. The central axis of the second through-hole 5011 is aligned with the central axis of the first through-hole. To accommodate digestion cups 401 of varying diameters within a certain size range, a variable diameter stopper is installed on the stopper plate 501 at the second through-hole 5011.

[0031] Specifically, in this embodiment, the disengagement mechanism also includes a guide shaft 502 connected to the support plate 201, and a support plate 503 and a spring 504 arranged on the guide shaft 502 from top to bottom, and the central axis of the guide shaft 502 is parallel to the central axis of the first through hole; the support plate 503 is slidably connected to the guide shaft 502 and is located below the support plate 201; the limit plate 501 is connected to the guide shaft 502, and is located below the support plate 201; one end of the spring 504 is connected to the support plate 503, and the other end is connected to the limit plate 501; a third through hole with a diameter smaller than the diameter of the limit ring 4011 is provided on the support plate 503, and the diameter of the third through hole is greater than or equal to the outer diameter of the digestion cup 401; the central axis of the third through hole is collinear with the central axis of the first through hole.

[0032] from Figure 1 or Figure 2 From a 3D perspective, when the digestion cup 401 is "fixed" on the support plate 201 by the release mechanism, the support plate 503 and the retaining ring 4011 on the digestion cup 401 prevent the digestion cup 401 from falling toward the heating plate 301. At the same time, due to the elastic force of the spring 504, a certain distance is maintained between the bottom of the digestion cup 401 and the heating plate 301 when not heating.

[0033] from Figure 1 or Figure 2 From a 3D perspective, after the sample water is added, the downward pressure mechanism is operated to move the digestion cup 401 toward the heating plate 301 until the bottom of the digestion cup 401 contacts the heating plate 301. The heating plate 301 then heats the liquid in the digestion cup 401. During this process, the spring 504 is in a compressed state. When heating is complete, the downward pressure mechanism moves upward. During this process, the digestion cup 401 automatically moves upward under the action of the spring 504, and it is separated from the heating plate 301.

[0034] Reference Figures 1-6 In this embodiment, the variable diameter limiting mechanism includes at least two groups of limiting units, and the two groups of limiting units are distributed in a circular array at the edge of the second through hole 5011.

[0035] Specifically, the arbitrary limiting unit includes a frame 601 mounted at the edge of the second through hole 5011, and an upper limiting shaft 602 and a lower limiting shaft 603 spaced apart from each other on the frame 601 from top to bottom. The upper limiting shaft 602 is rotatably connected to a limiting bar 604 and a torsion spring 605. The upper end of the torsion spring 605 is connected to the upper end of the limiting bar 604, and its lower end abuts the lower limiting shaft 603. The portion of the limiting bar 604 below the upper limiting shaft 602 is located between the lower limiting shaft 603 and the central axis of the second through hole 5011. A side of the limiting bar 604 away from the central axis of the second through hole 5011 is provided with an avoidance groove 6041 adapted to fit the lower limiting shaft 603, with the opening of the avoidance groove 6041 facing the lower limiting shaft 603. Furthermore, the contact surface between the limiting bar 604 and the digestion cup 401 can be designed as needed to ensure that the limiting bar 604 fully abuts the digestion cup 401.

[0036] from Figure 4 From the perspective of , when the digestion cup 401 is not placed in the second through hole 5011, the limiting bar 604 on the left tends to rotate counterclockwise around the upper limiting shaft 602 under the action of the elastic force of the torsion spring 605. When the digestion cup 401 is placed in the second through hole 5011, the digestion cup 401 "squeezes" the three limiting bars 604, causing the lower end of each limiting bar 604 to move toward the lower limiting shaft 603, and the lower limiting shaft 603 gradually gets stuck in the avoidance groove 6041. When the upper limiting ring 4011 of the digestion cup 401 abuts against the supporting plate 503, the digestion cup 401 stops moving toward the heating plate 301. At this time, the three limiting plates 501 abut against the outer wall of the digestion cup 401 under the action of the three torsion springs 605, thereby fixing the digestion cup 401 in the second through hole 5011 and centering it. The more or less the lower limit shaft 603 is inserted into the avoidance groove 6041, the more or less the diameter-changing limit mechanism can adapt to the digestion cups 401 of different diameters within a certain size range.

[0037] Specifically, in this embodiment, the downward pressure mechanism includes a lifting mechanism 701 arranged on the instrument frame 101, a mounting plate 702 connected to the execution end of the lifting mechanism 701, and a condenser 703 arranged on the mounting plate 702; the central axis of the condenser 703 is collinear with the central axis of the first through hole.

[0038] from Figure 1 or Figure 2 From the perspective of FIG, the lifting mechanism 701 drives the condenser 703 to move downward synchronously by controlling the downward movement of the mounting plate 702. When the lower end of the condenser 703 contacts the opening of the digestion cup 401, the condenser 703 continues to move downward until the bottom of the digestion cup 401 contacts the heating plate 301.

[0039] After the sample water in the digestion cup 401 is heated by the heating plate 301, it generates water vapor at a certain temperature. Another function of the condenser 703 is to remove the heat from this water vapor. After the water vapor is cooled by the condenser 703, it liquefies and flows back into the digestion cup 401. In this way, the volume of the sample water in the digestion cup 401 does not decrease after being heated and boiled for a period of time. The working principle of the condenser 703 is prior art and will not be described in detail here.

[0040] In this embodiment, four digestion cups 401 form a group, so the number of condensing tubes 703 on the corresponding mounting plate 702 is also four.

[0041] In this embodiment, the lifting mechanism 701 is a screw-nut mechanism. In other implementations of this embodiment, the lifting mechanism 701 can also use a linear motion mechanism such as a linear motor 1002 and a hydraulic rod to control the lifting of the mounting plate 702.

[0042] Reference Figure 1 and Figure 2 To facilitate the addition of reagents to the digestion cup 401, a liquid-adding mechanism is also mounted on the instrument frame 101. The liquid-adding mechanism includes an upper liquid-adding mechanism for adding liquid to the condenser 703 and a lower liquid-adding mechanism for adding liquid to the digestion cup 401. The upper liquid-adding mechanism includes a first liquid-adding arm 801 that is both linearly movable and rotatable, and is provided with a first liquid-adding port. The lower liquid-adding mechanism includes a second liquid-adding arm 901 that is both linearly movable and rotatable, and is provided with a second liquid-adding port. The linear movement of the first and second liquid-adding arms 801, 901, is controlled by a screw-nut mechanism.

[0043] When the condenser 703 moves to the bottom, the lower end of the condenser 703 is docked with the opening of the digestion cup 401. At this time, the first liquid adding arm 801 can be controlled to move so that the first liquid adding port on it is located directly above the upper end opening of the condenser 703. At this time, the corresponding reagent can be injected into the condenser 703, and the corresponding reagent then flows into the digestion cup 401.

[0044] When the condenser 703 moves to the top and separates from the digestion cup 401, the lower port of the condenser 703 is separated from the opening of the digestion cup 401. At this time, the second liquid adding arm 901 can be controlled to move so that the second liquid adding port on it is located directly above the opening of the digestion cup 401. At this time, the corresponding reagent can be injected into the digestion cup 401.

[0045] Reference Figure 2 and Figure 7In this embodiment, the second liquid-adding arm 901 is further equipped with a mixing mechanism for mixing the liquid in the digestion cup 401. When the second liquid-adding arm 901 moves to the digestion cup 401, the mixing mechanism is located below the heating plate 301. Specifically, the mixing mechanism includes a cantilever 1001 connected to the second liquid-adding arm 901, a motor 1002 mounted on the cantilever 1001, a turntable 1003 connected to the output shaft of the motor 1002, and a first magnet 1004 and a second magnet 1005 installed at intervals on the turntable 1003. The magnetic poles of the first magnet 1004 and the second magnet 1005 are reversed. In addition, a magnet is also placed inside the digestion cup 401.

[0046] In this way, when the liquid addition is completed, the first magnet 1004 and the second magnet 1005 are located directly below the digestion cup 401, and the motor 1002 drives the turntable 1003 to rotate. The rotation of the turntable 1003 drives the first magnet 1004 and the second magnet 1005 to rotate. The magnetic attraction force generated by the rotation of the first magnet 1004 and the second magnet 1005 acts on the magnet in the digestion cup 401. This magnetic attraction force causes the magnet in the digestion cup 401 to displace or rotate, thereby achieving the purpose of mixing the liquid in the digestion cup 401.

[0047] In addition, refer to Figure 1 The second liquid adding arm 901 is also equipped with a camera 1101 and a color sensor 1102, which move linearly and rotate together with the second liquid adding arm 901. The function of the camera 1101 and the color sensor 1102 is to observe the color change of the liquid in the digestion cup 401 for judgment and detection.

[0048] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Instead, the present invention can be used in various other combinations, modifications, and environments and can be modified within the scope of the concept described herein through the above teachings or techniques or knowledge in the relevant fields. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention are intended to be protected by the claims appended hereto.

Claims

1. A COD analyzer adaptable to digestion cups of different diameters, comprising an instrument frame (101), wherein a support plate (201) and a heating plate (301) are arranged on the instrument frame (101) from top to bottom, and the support plate (201) and the heating plate (301) are parallel to each other; a limiting ring (4011) is provided on the body of the digestion cup (401) near its opening; and the characteristics are: The instrument frame (101) is provided with a downward pressing mechanism, which makes the bottom of the digestion cup (401) fit against the heating plate (301) during heating; The support plate (201) is provided with a first through hole adapted to the limiting ring (4011); The support plate (201) is provided with a disengagement mechanism adapted to the digestion cup (401), and the disengagement mechanism comprises a limiting plate (501) connected to the support plate (201); the limiting plate (501) is provided with a second through hole (5011) adapted to the digestion cup (401), and the central axis of the second through hole (5011) is collinear with the central axis of the first through hole; the limiting plate (501) is provided with a variable diameter limiting mechanism at the second through hole (5011).

2. A COD analyzer adaptable to digestion cups of different diameters according to claim 1, characterized in that: The disengagement mechanism further comprises a guide shaft (502) connected to the support plate (201), and a support plate (503) and a spring (504) sequentially arranged on the guide shaft (502) from top to bottom, wherein the central axis of the guide shaft (502) is parallel to the central axis of the first through hole; the support plate (503) is slidably connected to the guide shaft (502) and is located below the support plate (201); the limiting plate (501) is connected to the guide shaft (502) and is located below the support plate (503); one end of the spring (504) is connected to the support plate (503), and the other end is connected to the limiting plate (501); a third through hole having a diameter smaller than that of the limiting ring (4011) is provided on the support plate (503), and the diameter of the third through hole is greater than or equal to the outer diameter of the digestion cup (401); the central axis of the third through hole is collinear with the central axis of the first through hole.

3. A COD analyzer adaptable to digestion cups of different diameters according to claim 2, characterized in that: The variable diameter limiting mechanism comprises at least two groups of limiting units, and the two groups of limiting units are distributed in a circular array at the edge of the second through hole (5011).

4. A COD analyzer adaptable to digestion cups of different diameters according to claim 3, characterized in that: Any of the limit units comprises a frame (601) arranged at the edge of the second through hole (5011), and an upper limit shaft (602) and a lower limit shaft (603) arranged on the frame (601) at intervals from top to bottom, wherein the upper limit shaft (602) is rotatably connected to the limit bar (604) and the torsion spring (605); the upper end of the torsion spring (605) is connected to the upper end of the limit bar (604), and the lower end thereof abuts against the lower limit shaft (603); the portion of the limit bar (604) located below the upper limit shaft (602) is located between the lower limit shaft (603) and the central axis of the second through hole (5011).

5. A COD analyzer adaptable to digestion cups of different diameters according to claim 4, characterized in that: A side of the limiting strip (604) away from the central axis of the second through hole (5011) is provided with an avoidance groove (6041) adapted to the lower limiting axis (603), and the opening of the avoidance groove (6041) faces the lower limiting axis (603).

6. A COD analyzer adaptable to digestion cups of different diameters according to claim 1, characterized in that: The pressing mechanism includes a lifting mechanism (701) arranged on the instrument frame (101), a mounting plate (702) connected to the execution end of the lifting mechanism (701), and a condensing tube (703) arranged on the mounting plate (702); the central axis of the condensing tube (703) is collinear with the central axis of the first through hole.

7. A COD analyzer adaptable to digestion cups of different diameters according to claim 6, characterized in that: The instrument skeleton (101) is also provided with a liquid adding mechanism, which includes an upper liquid adding mechanism for adding liquid into the condenser (703) and a lower liquid adding mechanism for adding liquid into the digestion cup (401).

8. A COD analyzer adaptable to digestion cups of different diameters according to claim 7, characterized in that: The upper liquid adding mechanism comprises a first liquid adding arm (801) that is both linearly movable and rotatable, and a first liquid adding port is provided on the first liquid adding arm (801).

9. The COD analyzer adaptable to digestion cups of different diameters according to claim 7, characterized in that: The lower liquid adding mechanism comprises a second liquid adding arm (901) that is both linearly movable and rotatable, and a second liquid adding port is provided on the second liquid adding arm (901).

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