Thin-layer chromatography sample applicator for biomass energy product detection

Abstract

The invention discloses a thin-layer chromatography sample applicator for biomass energy product detection, and relates to the technical field of biological analysis instruments.The thin-layer chromatography sample applicator comprises a sample application table, the upper surface of the sample application table is fixedly connected with a supporting frame, one side of the supporting frame is fixedly connected with a small motor, and the inner wall of the supporting frame is rotationally connected with a threaded rod; the output shaft of the small motor penetrates through one end of the inner wall of the supporting frame and is fixedly connected with the threaded rod, so that sample application operation of a plurality of samples with different concentrations or different samples can be completed at one time, the injector does not need to be manually and repeatedly cleaned to suck a next sample solution for sample application, the sample application time is greatly shortened, and especially when a large number of biological contrast experiments need to be repeated, the sample application efficiency is greatly improved. The whole working efficiency can be remarkably improved, meanwhile, the samples with different concentrations can be subjected to subsequent operation such as expansion and color development under the same time and the same environment condition through sample application, so that the comparison among the samples with different concentrations is more accurate, and the errors of the capacity and the position of the samples subjected to manual sample application can be avoided.

Description

Technical Field

[0001] The invention relates to the technical field of biological analysis instruments, in particular to a thin layer chromatography spotter for detecting biomass energy products. Background Art

[0002] The thin layer chromatography spotter used for biomass energy product testing is an instrument that plays a key role in thin layer chromatography technology and is specifically used in the testing and analysis of biomass energy-related products. It accurately adds the sample solution of the biomass energy product to a specific position on the thin layer chromatography plate (usually a thin plate coated with a stationary phase such as silica gel). After a series of operations such as development and color development, the different components in the sample are separated on the thin layer plate and appear as different spots, thereby achieving qualitative or quantitative analysis of various components in the biomass energy product.

[0003] Traditional thin layer chromatography spotters usually only have one spotting needle or nozzle for aspiration and spotting. For example, in biological research experiments, it is necessary to compare the performance differences of high-concentration and low-concentration biomass sample solutions on thin layer chromatography, or for the same type of biomass products, such as biodiesel, if its raw materials come from different vegetable oils (such as soybean oil, rapeseed oil, palm oil, etc.), spotting and comparing biodiesel sample solutions from different sources can analyze the subtle changes in composition caused by differences in raw materials. However, the operator can only operate one spotting nozzle for spotting and then manually clean the spot. The sample needle is used to draw low-concentration samples for spotting. The operation process is cumbersome, and manual operation one by one will greatly slow down the progress of the experiment. Especially in scenarios such as large-scale, multi-batch quality inspection, this low efficiency problem is more prominent, and there will inevitably be some errors in the manual operation process, such as the position accuracy of each spotting, subtle differences in the spotting amount, etc. When comparing high-concentration and low-concentration sample solutions, these human errors may cause the spots finally presented on the thin-layer chromatography plate to fail to truly reflect the impact of concentration differences, thereby affecting the accurate comparison and judgment of sample properties, composition changes, etc.

[0004] In view of this, the present invention provides a thin layer chromatography sample spotter for detecting biomass energy products. Summary of the Invention

[0005] In view of the deficiencies of the prior art, the present invention provides a thin layer chromatography spotter for detecting biomass energy products, which is used to solve the problems raised in the above background technology.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: The cam is fixedly mounted on one side of the support frame and is provided with a plurality of movable members, and the movable members are connected to the movable member by a plurality of movable members.

[0007] Preferably, a ventilation clamping assembly for sequential ventilation is provided on the U-shaped sleeve, and the ventilation clamping assembly includes an air pump fixedly connected to the U-shaped sleeve, and a hose is fixedly connected to the air outlet end of the air pump. A plurality of branch pipes are evenly fixedly connected to each hose, and the connecting pipe is threadedly connected to the branch pipe. A plurality of positioning holes are provided on the U-shaped sleeve, and U-shaped frames are inserted into several of the positioning holes.

[0008] Preferably, a U-shaped jacket is slidably connected in each U-shaped frame, a support spring is fixedly connected between the U-shaped jacket and the adjacent U-shaped frame, and the connecting pipe is threadedly connected to the corresponding branch pipe.

[0009] Preferably, the telescopic end of the electric push rod is fixedly connected to a resistance rod, which is squeezed into a U-shaped jacket. The U-shaped jacket is made of elastic metal plate, and the part of the connecting pipe located inside the U-shaped jacket is made of soft rubber.

[0010] Preferably, a distance adjustment component is provided on the U-shaped sleeve, and the distance adjustment component includes an L-shaped plate fixedly connected to the U-shaped sleeve, and a movable column is slidably connected to the L-shaped plate.

[0011] Preferably, one end of the movable column passing through the L-shaped plate is fixedly connected to the limiting tooth, and the outer surface of the movable column is sleeved with a limiting spring.

[0012] Preferably, one end of the limit spring is fixedly connected to the L-shaped plate, and the other end of the limit spring is fixedly connected to one end of the movable column. A plurality of protruding teeth are evenly fixedly connected to one side of the movable column close to the limit tooth.

[0013] The present invention provides a thin layer chromatography spotter for biomass energy product detection, which has the following beneficial effects: By completing the spotting operation of multiple concentrations or different samples at one time, there is no need to manually clean the syringe repeatedly to draw the next sample solution for spotting, which greatly shortens the spotting time. Especially when a large number of such biological comparison experiments need to be repeated, it can significantly improve the overall work efficiency. At the same time, spotting samples of different concentrations can ensure that these samples are subsequently developed, colored, and other operations are carried out at the same time and under the same environmental conditions (such as the material of the thin layer plate, the volatilization of the developing agent, temperature, etc.), making the comparison between samples of different concentrations more accurate and avoiding errors in the volume and position of manually spotted samples.

[0014] The U-shaped jacket can automatically clamp the connecting tubes of multiple unused spotting nozzles, so that the gas ejected by the air pump can be concentrated on one spotting nozzle, avoiding the interference of the spotting nozzle sample that is ejecting the sample caused by the gas ejected by other spotting nozzles at the same time.

[0015] By adjusting the distance between multiple spotting nozzles, for samples with high volatility, the spotting distance between other samples can be appropriately increased to reduce the impact of each other due to volatilization, ensuring that each sample can be developed and analyzed as much as possible according to the expected amount. For samples with low volatility, the spotting distance between other samples can be appropriately reduced to avoid wasting the effective use area of ​​the thin layer plate.

[0016] The detachable design allows the sample nozzle to be separated from the sampler body, facilitating targeted cleaning of the nozzle's internal channels, tip, and other areas where sample residue is likely to remain. For samples that are highly viscous, prone to crystallization, or contain particles, cleaning the detachable nozzle separately can more thoroughly remove residue and avoid cross-contamination between different samples.

[0017] For high-viscosity sample solutions with poor fluidity, the distance between the nozzle and the thin layer plate can be appropriately shortened. The impact force when the nozzle sprays the solution can be used to help the high-viscosity sample spread better on the thin layer plate, facilitating subsequent analysis. For highly volatile samples, shortening the distance between the nozzle and the thin layer plate can reduce the volatilization loss of the sample solution from the nozzle spraying to contacting the thin layer plate. The appropriate distance between the sample nozzle and the thin layer plate can minimize the impact of solvent volatilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the installation of the three-dimensional structure of the present invention; Figure 2 This is a schematic diagram of the installation of the movable column, spotting nozzle and U-shaped sleeve plate of the present invention; Figure 3 For the present invention Figure 2 A diagram showing the enlarged installation of area A; Figure 4This is a schematic diagram of the installation of the air pump, hose, branch pipe and other structures of the present invention; Figure 5 For the present invention Figure 4 Enlarged installation diagram of area B in the middle; Figure 6 This is a schematic diagram of the installation of the U-shaped sleeve, positioning holes, and U-shaped frame structures of the present invention; Figure 7 For the present invention Figure 6 Enlarged installation diagram of area D in the middle; Figure 8 This is a schematic diagram of the rear-view stereo installation of the present invention; Figure 9 For the present invention Figure 8 Enlarged installation diagram of area E in the middle.

[0019] In the picture: 1. Spotting table; 2. Support frame; 3. Small motor; 4. Threaded rod; 5. Moving column; 51. Electric push rod 1; 52. Electric push rod 2; 53. U-shaped sleeve; 54. Spotting nozzle; 55. Syringe; 56. Raised plate; 57. Bolt; 58. Screw hole; 59. Connecting pipe; 6. Air pump; 61. Hose; 62. Branch pipe; 63. Positioning hole; 64. U-shaped frame; 65. Support spring; 66. U-shaped jacket; 67. Resistance rod; 7. L-shaped plate; 71. Movable column; 72. Limit spring; 73. Limit tooth; 74. Raised tooth. DETAILED DESCRIPTION

[0020] Embodiments of the present invention: See also Figures 1 to 5 and Figure 6 、 Figure 8, a thin layer chromatography spotter for detecting biomass energy products, including a spotting platform 1, the upper surface of the spotting platform 1 is fixedly connected to a support frame 2, one side of the support frame 2 is fixedly connected to a small motor 3, the inner wall of the support frame 2 is rotatably connected to a threaded rod 4, the output shaft of the small motor 3 passes through one end of the inner wall of the support frame 2 and is fixedly connected to the threaded rod 4, the outer surface of the threaded rod 4 is threadedly connected to a moving column 5, the inner wall of the support frame 2 is fixedly connected to a sliding rod, the moving column 5 is slidably connected to the sliding rod, and is used to limit the moving column 5 so that it can only move horizontally, an electric push rod 1 51 is fixedly connected to the moving column 5, the electric push rod 1 51 passes through the telescopic end of one end of the moving column 5 and is fixedly connected to the electric push rod 2 52, the telescopic end of the electric push rod 2 52 is fixedly connected to the pressing plate, and the moving column 5 is slidably connected to the moving column 5. There is a U-shaped sleeve 53, a through groove is provided in the middle of the U-shaped sleeve 53, a plurality of sample nozzles 54 are provided in the through groove of the U-shaped sleeve 53, and syringes 55 are inserted in the plurality of sample nozzles 54. The outer surfaces of the plurality of sample nozzles 54 are fixedly connected with a convex plate 56, and each convex plate 56 is threadedly connected with a bolt 57. A plurality of screw holes 58 are evenly provided on the side of the U-shaped sleeve 53 close to the convex plate 56, and each sample nozzle 54 is rotatably connected to a connecting tube 59 on the side away from the convex plate 56. A scale line is provided on the side of the U-shaped sleeve 53 close to the convex plate 56. An operation screen and a controller are provided on the sample station 1, and the movement of the movable column 5, as well as the movement of the electric push rod 1 51 and the electric push rod 2 52 can be controlled by the operation screen and the controller.

[0021] See also Figures 4 to 7 The U-shaped sleeve 53 is provided with a sequentially ventilated ventilating clamping assembly. The ventilating clamping assembly includes an air pump 6 fixedly connected to the U-shaped sleeve 53. The outlet end of the air pump 6 is fixedly connected to a hose 61. Each hose 61 is evenly fixedly connected to multiple branch pipes 62. The connecting pipe 59 is threadedly connected to the branch pipes 62. The U-shaped sleeve 53 is provided with multiple positioning holes 63, and several positioning holes 63 are inserted into U-shaped frames 64. The bottom of the U-shaped frame 64 is fixedly connected to a plug post that matches the positioning holes 63. The U-shaped sleeve 53 is provided with a through slot for the connecting pipe 59 to be inserted. The through slot supports the connecting pipe 59, which can limit the multiple sample nozzles 54 to the same height, ensuring that the distance between subsequent samples sprayed onto the thin layer plate is consistent. Each U-shaped frame 64 is slidably connected to a U-shaped jacket 66. A support spring 65 is fixedly connected between the U-shaped jacket 66 and the adjacent U-shaped frame 64. The connecting pipe 59 is threadedly connected to the corresponding branch pipe 62. refer to Figure 7As shown, the upper surface of the U-shaped jacket 66 away from the support spring 65 is provided with an outward-expanding inclined plate and a vertical plate. The vertical plate is used to contact the resistance rod 67, and the inclined plate is used to smoothly contact the connecting tube 59 for squeezing and closing. The telescopic end of the electric push rod 51 is fixedly connected with the resistance rod 67, and the resistance rod 67 is squeezed and fitted with the U-shaped jacket 66. The U-shaped jacket 66 is made of elastic metal plate, and the part of the connecting tube 59 located in the U-shaped jacket 66 is made of soft rubber, which facilitates the U-shaped jacket 66 to squeeze the connecting tube 59 to close.

[0022] See also Figure 8 、 Figure 9 A distance adjustment component is provided on the U-shaped sleeve 53, and the distance adjustment component includes an L-shaped plate 7 fixedly connected to the U-shaped sleeve 53, and a movable column 71 is slidably connected to the L-shaped plate 7, and one end of the movable column 71 passing through the L-shaped plate 7 is fixedly connected to the limiting tooth 73, and the outer surface of the movable column 71 is sleeved with a limiting spring 72, one end of the limiting spring 72 is fixedly connected to the L-shaped plate 7, and the other end of the limiting spring 72 is fixedly connected to one end of the movable column 71, and a plurality of convex teeth 74 are evenly fixedly connected to the side of the movable column 5 close to the limiting tooth 73, and the limiting tooth 73 is meshed with the plurality of convex teeth 74.

[0023] The following is the entire working process and working principle of the above embodiment: When using for the first time, first manually aspirate multiple different sample solutions into multiple syringes 55, and then insert them into the sample spotting nozzles 54 in sequence, then place the thin layer plate on the upper surface of the sample spotting table 1, and turn on the heating of the thin layer plate through the operation screen to facilitate the adsorption of subsequent sample spotting. After that, the electric push rod 1 51 starts to drive the electric push rod 2 52 to move, so that the pressure plate is close to the syringe 55 where the sample needs to be spotted, that is, above the syringe 55 closest to the moving column 5. When the electric push rod 1 51 starts to move its telescopic end, the resistance rod 67 fixed at its telescopic end will first resist the U-shaped jacket 66 close to the side of the moving column 5. For details, please refer to Figure 5 The resistance rod 67 will push the U-shaped jacket 66 to slide in the U-shaped frame 64 and compress the corresponding support spring 65. At this time, the U-shaped jacket 66 no longer squeezes and closes the corresponding connecting pipe 59, so that the connecting pipe 59 is connected to the hose 61 and the sample nozzle 54, and the air pump 6 is turned on under the control of the controller in the sample station 1. Since the connecting pipes 59 on the other multiple sample nozzles 54 are clamped by the U-shaped jacket 66, the air pump 6 will continuously transmit gas to the connected connecting pipes 59 and the sample nozzle 54 after it is turned on. In conjunction with the electric push rod 2 52, the pressure plate is driven to press down the piston rod of the syringe 55, and the sample solution in the corresponding syringe 55 is injected into the sample nozzle 54. Then, under the pressure of the gas, the sample solution can be ejected from the sample nozzle 54. In conjunction with the small motor 3, the threaded rod 4 is driven to rotate, so that the moving column 5 drives the sample nozzle 54 that is ejecting the sample to move horizontally synchronously, and a strip of sample can be ejected.

[0024] When the U-shaped sleeve 66 is no longer in contact with the previous U-shaped sleeve 66, the support spring 65 is reset to drive the previous U-shaped sleeve 66 to slide and reset, squeezing the soft rubber tube part of the corresponding connecting tube 59 to compress and close it, so that the sampling nozzle 54 will no longer spray gas after the sampling, and the resistance rod 67 will contact the previous U-shaped sleeve 66. Next, the U-shaped jacket 66 on the sample connecting tube 59 needs to be sprayed out, so that the corresponding connecting tube 59 is connected to the hose 61 and the sample spotting nozzle 54, and the above steps can be repeated to spot the sample solution in the next syringe 55. Subsequently, the above steps can be continued to spot the sample solutions of multiple syringes 55, so that the spotting operation of multiple concentrations or different samples can be completed at one time. There is no need to manually clean the syringe 55 repeatedly to absorb the next sample solution for spotting, which greatly shortens the spotting time. Especially when a large number of such biological comparison experiments need to be repeated, the overall work efficiency can be significantly improved. At the same time, spotting samples of different concentrations can ensure that these samples are subjected to subsequent development, color development and other operations under the same time and the same environmental conditions (such as the material of the thin layer plate, the volatilization of the developing agent, the temperature, etc.), making the comparison between samples of different concentrations more accurate and avoiding errors in the volume and position of the sample spotted manually.

[0025] The U-shaped jacket 66 can automatically clamp the connecting tubes 59 on multiple unused sampling nozzles 54, so that the gas ejected by the air pump 6 can be concentrated on one sampling nozzle 54, thereby preventing the gas ejected by other sampling nozzles 54 from interfering with the sample of the sampling nozzle 54 that is ejecting the sample.

[0026] Furthermore, different samples may experience different development speeds and diffusion extents under the same developing agent. For example, some small molecules and highly polar compounds develop relatively quickly on the thin layer plate, and the spots tend to spread widely; whereas large molecules and less polar compounds may develop more slowly and have a relatively smaller diffusion range. If the spotting distance is too close, after the development operation, the spots may contact and overlap with each other, making it impossible to accurately distinguish the spot characteristics corresponding to each sample, affecting the qualitative and quantitative analysis of the sample components. Therefore, for samples with large differences in development speed, appropriately increasing the spotting distance can ensure clear boundaries between the spots after development, facilitating observation and analysis. In actual use, the spotting distance between each sample solution can be adjusted according to the development and volatilization conditions of different samples.

[0027] The specific operation is as follows: start the electric push rod 1 51 through the operation screen to drive the electric push rod 2 52 and the interference rod 67 to reset to the initial position, that is, the position closest to the moving column 5, to ensure that the interference rod 67 does not contact any U-shaped sleeve 66, and then manually thread the bolt 57 to disengage it from the convex plate 56 and the corresponding screw hole 58 on the sample nozzle 54. Then, adjust the distance between the multiple sample nozzles 54 according to the development speed and diffusion degree of different sample solutions, and accurately adjust it in conjunction with the scale line on the U-shaped sleeve 53. After the adjustment is completed, pass the corresponding bolt 57 from the convex plate 56 and then screw it into the screw hole 58 to fix it. When the sample nozzle 54 moves, it will also pull the corresponding branch pipe through the connecting pipe 59. 62 and the hose 61 are deformed and moved, and then it is necessary to hold the U-shaped frame 64 and pull it upward to disengage the plug at the bottom of the U-shaped frame 64 from the corresponding positioning hole 63, and then plug the U-shaped frame 64 into the positioning hole 63 near the position of the connecting pipe 59, so that the U-shaped jacket 66 can clamp the corresponding connecting pipe 59, so as to achieve the effect of adjusting the distance between multiple sampling nozzles 54. For samples with strong volatility, the sampling distance between other samples can be appropriately increased to reduce the influence of each other due to volatilization, ensuring that each sample can be expanded and analyzed as much as possible according to the expected amount. For samples with low volatility, the sampling distance between other samples can be appropriately reduced to avoid wasting the effective use area of ​​the thin layer plate.

[0028] Furthermore, the entire spotting nozzle 54 can be removed by manually threading the connecting bolt 57 to disengage it from the convex plate 56 and the screw hole 58, and then rotating the connecting tube 59 on the spotting nozzle 54 to disconnect it from the branch tube 62. The detachable design allows the spotting nozzle 54 to be separated from the main body of the spotter, making it convenient for targeted cleaning of the internal channels, tip, and other parts of the nozzle where sample residues are likely to remain. For samples that are highly viscous, prone to crystallization, or contain particles, cleaning the detachable nozzle separately can more thoroughly remove residues and avoid cross-contamination between different samples.

[0029] Further, in time use, the movable column 71 can also be held to slide on the L-shaped plate 7, and the corresponding limiting spring 72 can also be stretched, and the limiting tooth 73 can also drive the engagement with the plurality of convex teeth 74, and then the U-shaped sleeve plate 53 can be slid up and down on the moving column 5, that is, the distance between the sample jet head 54 and the sample stage 1 thin layer plate can be adjusted. After the adjustment is completed, the movable column 71 is loosened, and the limiting spring 72 will drive the limiting tooth 73 to engage with the convex tooth 74 under the action of the reset, that is, the position of the adjusted U-shaped sleeve plate 53 can be limited and fixed, so that the distance between the sample jet head 54 and the sample stage 1 thin layer plate is fixed. For high-viscosity sample solutions with poor flowability, appropriately shortening the distance between the jet head and the thin layer plate can utilize the impact force of the jet head when the solution is sprayed to help the high-viscosity sample to spread better on the thin layer plate, which is convenient for subsequent development analysis. For samples with strong volatility, shortening the distance between the jet head and the thin layer plate can reduce the volatilization loss of the sample solution from the jet head to the contact thin layer plate within a short time. The distance between the sample jet head 54 and the thin layer plate can minimize the influence of solvent volatilization.

[0030] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A thin layer chromatography sample spotter for biomass energy product detection, comprising a sample spotting station (1), characterized in that: The upper surface of the spotting table (1) is fixedly connected to a support frame (2), one side of the support frame (2) is fixedly connected to a small motor (3), the inner wall of the support frame (2) is rotatably connected to a threaded rod (4), the output shaft of the small motor (3) passes through one end of the inner wall of the support frame (2) and is fixedly connected to the threaded rod (4), the outer surface of the threaded rod (4) is threadedly connected to a moving column (5), the moving column (5) is fixedly connected to an electric push rod 1 (51), the electric push rod 1 (51) passes through the telescopic end of one end of the moving column (5) and is fixedly connected to an electric push rod 2 (52), the moving column (5) A U-shaped sleeve (53) is slidably connected to the upper portion, a through groove is provided in the middle of the U-shaped sleeve (53), a plurality of sample nozzles (54) are provided in the through groove of the U-shaped sleeve (53), a syringe (55) is inserted into each of the plurality of sample nozzles (54), and a convex plate (56) is fixedly connected to the outer surface of the plurality of sample nozzles (54), a bolt (57) is threadedly connected to each convex plate (56), a plurality of screw holes (58) are uniformly provided on one side of the U-shaped sleeve (53), and a connecting pipe (59) is rotatably connected to the side of each sample nozzle (54) away from the convex plate (56).

2. The thin layer chromatography sample spotter for biomass energy product detection according to claim 1, characterized in that: A ventilation clamping assembly for sequential ventilation is provided on the U-shaped sleeve (53), and the ventilation clamping assembly includes an air pump (6) fixedly connected to the U-shaped sleeve (53), a hose (61) is fixedly connected to the air outlet end of the air pump (6), and each hose (61) is evenly fixedly connected to a plurality of branch pipes (62), and the connecting pipe (59) is threadedly connected to the branch pipe (62). A plurality of positioning holes (63) are opened on the U-shaped sleeve (53), and U-shaped frames (64) are inserted into several of the positioning holes (63).

3. The thin layer chromatography sample spotter for biomass energy product detection according to claim 2, characterized in that: A U-shaped jacket (66) is slidably connected in each U-shaped frame (64), a support spring (65) is fixedly connected between the U-shaped jacket (66) and the adjacent U-shaped frame (64), and the connecting pipe (59) is threadedly connected to the corresponding branch pipe (62).

4. The thin layer chromatography sample spotter for biomass energy product detection according to claim 3, characterized in that: The telescopic end of the electric push rod 1 (51) is fixedly connected to a resistance rod (67), and the resistance rod (67) is squeezed and matched with the U-shaped jacket (66). The U-shaped jacket (66) is made of elastic metal plate, and the part of the connecting pipe (59) located in the U-shaped jacket (66) is made of soft rubber.

5. The thin layer chromatography sample spotter for biomass energy product detection according to claim 1, characterized in that: A distance adjustment assembly is provided on the U-shaped sleeve (53), and the distance adjustment assembly comprises an L-shaped plate (7) fixedly connected to the U-shaped sleeve (53), and a movable column (71) is slidably connected to the L-shaped plate (7).

6. The thin layer chromatography spotter for biomass energy product detection according to claim 5, characterized in that: One end of the movable column (71) passing through the L-shaped plate (7) is fixedly connected to the limiting tooth (73), and the outer surface of the movable column (71) is sleeved with a limiting spring (72).

7. The thin layer chromatography spotter for biomass energy product detection according to claim 6, characterized in that: One end of the limit spring (72) is fixedly connected to the L-shaped plate (7), and the other end of the limit spring (72) is fixedly connected to one end of the movable column (71). A plurality of convex teeth (74) are evenly fixedly connected to one side of the movable column (5) close to the limit tooth (73).

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