Crystallization device for refining and preparing propacetamol hydrochloride

Abstract

The utility model belongs to the technical field of propacetamol hydrochloride refining equipment, and particularly relates to a propacetamol hydrochloride refining preparation crystallization device which comprises a crystallization barrel, a cover plate is arranged at the top of the crystallization barrel, a shaft hole is formed in the cover plate, a rotating shaft is arranged in the shaft hole in a matched and penetrating mode, and the rotating shaft is vertically and downwards in transmission connection to a rotating motor fixedly installed at the bottom of the crystallization barrel. The part, located in the barrel cavity of the crystallization barrel, of the rotating shaft extends outwards at intervals to form a plurality of connecting rods, vertical mounting rods are fixedly connected to the ends, away from the rotating shaft, of the connecting rods in the length direction at the same time, and the rod sections, located between every two adjacent connecting rods, of the mounting rods are tightly wrapped by flexible sleeves in a sleeving mode; the rotating motor drives the rotating shaft to axially rotate through the driving shaft, so that the flexible sleeve is driven to be in contact with the inner side wall of the crystallization barrel and slide back and forth.

Description

Technical Field

[0001] The utility model belongs to the technical field of propacetamol hydrochloride refining equipment, and particularly relates to a crystallization device for refining and preparing propacetamol hydrochloride. Background Art

[0002] Propacetamol hydrochloride is a non-addictive analgesic that can be used for intravenous or intramuscular injection. Clinically, it is mainly used to treat and relieve pain by releasing acetaminophen after being hydrolyzed by plasma esterase. During the preparation process, the crude product of propacetamol hydrochloride needs to be hot-dissolved in ethanol, and activated carbon is added for stirring and decolorization. After the activated carbon is separated, the clear night is cooled and crystallized, and then the resulting crystals are washed and dried to obtain propacetamol hydrochloride with higher purity. Among them, crystallization usually occurs in a crystallization barrel. During the crystallization process, a part of the crystals will be attached to the inner wall of the crystallization barrel and will not fall off easily, which affects the yield of propacetamol hydrochloride after refining. If the part of the crystals attached to the inner wall of the crystallization barrel is cleaned and scraped off manually, the efficiency is often low; and if a cleaning and scraping mechanism is set in the crystallization barrel, it is indeed possible to scrape off the crystals on the barrel wall in real time during the crystallization process, but because the scraping mechanism continues to slide on the barrel wall, it will cause continuous noise generation, causing noise pollution. Summary of the invention

[0003] In order to solve the above technical problems, the utility model provides a crystallization device for refining and preparing propacetamol hydrochloride, comprising a cylindrical crystallization barrel with a vertical axis, a cooling coil is evenly coiled inside the cylindrical vertical barrel plate of the crystallization barrel, a plurality of support legs are evenly distributed in annular directions at intervals near the circumference of the bottom of the crystallization barrel, the top of the crystallization barrel is open and is equipped with a cover plate with a horizontal plate surface for covering the top opening of the crystallization barrel, and the cover plate and the crystallization barrel are coaxially arranged.

[0004] A number of threaded holes are evenly distributed in the circumferential direction near the peripheral edge of the cover plate, and the axial direction is vertical and connected to the upper and lower plate surfaces of the cover plate. A threaded groove is provided on the top edge of the crystallization barrel corresponding to the threaded holes. The threaded groove is formed by a local vertical downward depression on the top edge of the crystallization barrel. After the bolt thread fits through the threaded hole, it is further threaded and fully screwed into the threaded groove corresponding to the threaded hole, so that the cover plate can be fixed to cover the crystallization barrel.

[0005] The cover plate is provided with an axial hole which is coaxially arranged with the cover plate and connected with the upper and lower surfaces of the cover plate. A feed hole which is axially vertical and connected with the upper and lower surfaces of the cover plate is provided on the cover plate away from the axial hole. A rotating shaft is coaxially passed through the axial hole. The rotating shaft extends vertically downward into the barrel cavity of the crystallization barrel along its own axial direction.

[0006] A rotating motor is fixedly installed at the bottom of the crystallization barrel, and a driving shaft serving as the output end of the rotating motor is vertically extended upward from the rotating motor. The driving shaft is fixedly installed on the bottom plate of the crystallization barrel through a coaxial fit and can be axially rotatably and vertically upwardly sealed and extended into the barrel cavity of the crystallization barrel. The top of the driving shaft is vertically recessed downward to form a mounting groove which is coaxially arranged with the driving shaft and for the rotating shaft to be coaxially fitted and embedded. The top of the mounting groove is partially vertically recessed downward to form a receiving groove. A position on the shaft body of the rotating shaft near the bottom end of the rotating shaft partially protrudes outward along the radial direction of the rotating shaft to form a convex block. While the rotating shaft is vertically and coaxially fitted into the mounting groove, the convex block is vertically fitted and embedded in the accommodating groove, thereby realizing a transmission connection between the rotating shaft and the driving shaft. The rotating motor drives the rotating shaft to rotate axially on the crystallization barrel in turn through the driving shaft and the convex block. A discharge hole with a vertical axial direction and connected to the upper and lower plate surfaces of the bottom plate of the crystallization barrel is provided on the bottom plate of the crystallization barrel away from the rotating motor.

[0007] A plurality of connecting rods are arranged on the rotating shaft in the barrel cavity of the crystallization barrel at intervals along the length direction of the rotating shaft. The connecting rods are parallel to each other in the length direction. The connecting rods are formed by horizontally extending outward along the radial direction of the rotating shaft on the shaft body of the rotating shaft. The axially vertical mounting rod is fixedly connected to one end of each connecting rod away from the rotating shaft in the length direction. The two adjacent connecting rods on the mounting rod body are coaxially sleeved and tightly wrapped by flexible sleeves, and the flexible sleeves are made of rubber with smooth surface.

[0008] The rod body of the mounting rod is located between two adjacent connecting rods and protrudes horizontally outward along the radial direction of the mounting rod to form a limit strip which is vertical in the length direction. The inner wall of the flexible sleeve is evenly distributed with four vertical grooves in the length direction at intervals in the corresponding circumferential direction. Each groove is formed by the inner wall of the flexible sleeve being partially recessed horizontally outward along the radial direction of the flexible sleeve. The limit strip is parallelly fitted and embedded in one of the grooves to prevent relative axial rotation and slippage between the flexible sleeve and the mounting rod where it is located.

[0009] The flexible sleeve is horizontally pressed against the inner wall of the crystallization barrel through the connecting rods. When the rotating shaft rotates axially on the crystallization barrel, the flexible sleeve is driven to contact and fit the inner wall of the crystallization barrel through the connecting rods and the mounting rods.

[0010] The connecting rods, the mounting rods, and the flexible sleeves together form a first cleaning portion, and a second cleaning portion extends from a side of the rotating shaft away from the first cleaning portion. The first cleaning portion and the second cleaning portion are symmetrically arranged with respect to each other based on the rotating shaft.

[0011] Corresponding to the first cleaning part and the second cleaning part, the cover plate is provided with a strip-shaped through groove connecting the upper and lower plate surfaces of the cover plate on the left and right sides of the shaft hole for the first cleaning part or the second cleaning part to vertically upwardly cooperate and pass through the crystallization barrel. The horizontal shape of the strip-shaped through groove is the shape of the first cleaning part or the second cleaning part vertically upwardly projected on the cover plate.

[0012] The top axial end of the rotating shaft extends vertically upward with a cover plate, and fixed seats extend vertically upward on the cover plate at the front and rear sides of the shaft hole respectively. Each fixing seat is provided with a threaded mounting hole with the axial direction being horizontal in the front-to-back direction. The threaded mounting holes on the two fixing seats are aligned front to back, and a limit bolt located directly above the rotating shaft and close to the top end of the rotating shaft is threadedly fitted into the two threaded mounting holes.

[0013] The beneficial effects of this application are:

[0014] A flexible sleeve made of rubber is coated on the mounting rod near the side cavity wall in the inner cavity of the crystallization barrel. The flexible sleeve contacts and fits the inner wall of the crystallization barrel to slide relatively, so that the propacetamol hydrochloride crystal components attached to the inner wall of the crystallization barrel during the crystallization process are scraped off in real time, so that this part of the crystals can smoothly enter the next process together with the materials in the barrel, thereby reducing the loss during the crystallization process; further, by making the limit strip on the mounting rod parallelly fit into the embedded groove on the inner wall of the flexible sleeve and being clamped, relative axial rotation between the flexible sleeve and the mounting rod wrapped by it is avoided, thereby avoiding the rolling and slipping of the flexible sleeve on the inner wall of the crystallization barrel during the scraping process to reduce the scraping effect;

[0015] Compared with the use of hard scrapers, scrapers, etc. to contact and slide on the hard inner cavity wall of the crystallization barrel in order to scrape off the crystals attached to the inner wall of the crystallization barrel, which is easy to produce harsh and unpleasant friction noise, and this hard friction is also easy to cause wear of parts, in this solution, only the flexible sleeve made of rubber material contacts the inner cavity wall of the crystallization barrel, and under the support of each connecting rod and the mounting rod, when the flexible sleeve abuts against the inner cavity wall of the crystallization barrel, the flexible sleeve is squeezed to a moderate degree and will not be squeezed too tightly, so that the sound generated when the flexible sleeve contacts and fits the inner wall of the crystallization barrel and slides relatively to scrape off the crystals is greatly reduced, no obvious noise is emitted, and the production environment is purified;

[0016] In this solution, the connecting rod not only supports and connects the mounting rod and the flexible sleeve, but also stirs the material in the crystallization barrel when the shaft rotates axially.

[0017] Moreover, when the rotating motor stops running, the rotating shaft together with the first cleaning part and the second cleaning part can be taken out from the crystallization barrel as a whole through the shaft hole and the strip through groove on the cover plate: after the rotating motor stops running, the limiting bolts are first removed from the two fixing seats, and the rotating shaft is fully pulled upward away from the driving shaft, and then, with the first cleaning part and the second cleaning part upwardly pressed against the horizontal lower plate surface of the cover plate, the rotating shaft is slightly rotated so that the rotating shaft is also matched in the shaft hole and axially rotated until the first cleaning part and the second cleaning part correspond to the strip through groove on the cover plate one by one, and then the rotating shaft is further pulled vertically upward so that the first cleaning part and the second cleaning part respectively cooperate to pass through the corresponding strip through groove to leave the crystallization barrel. In this process, the lower edge of the shaft hole on the cover plate and the lower edge of the strip through groove can also push a small amount of crystals attached to the surface of the rotating shaft and the outer surface of the flexible sleeve downward into the crystallization barrel, thereby further reducing the loss during the crystallization process;

[0018] Considering that in this scheme, after the flexible sleeve is installed in the inner cavity of the crystallization barrel, it is always pressed against the inner cavity wall of the crystallization barrel and squeezed. Although the degree of squeezing here is moderate, after a long period of squeezing, it will still cause irreversible deformation of the squeezed part of the flexible sleeve, thereby causing the contact and fit between the flexible sleeve and the inner wall of the crystallization barrel to become loose, that is, the degree of scraping and interference of the flexible sleeve on the inner wall surface of the crystallization barrel during rotation is reduced, which is not conducive to the scraping off of the crystals attached to the inner wall. In this regard, the present solution provides a plurality of grooves at intervals in the circumferential direction on the inner cylinder wall of the flexible sleeve. After the rotating shaft together with the first cleaning part and the second cleaning part are taken out from the barrel cavity through the operation in the previous paragraph, the mounting rod is disassembled from each connecting rod, and the flexible sleeve is removed from the mounting rod, and the angle is changed and the mounting rod is coaxially fitted on the mounting rod again, and the mounting rod is then installed on the original connecting rods, and the rotating shaft together with the first cleaning part and the second cleaning part are installed into the barrel cavity in the original way. At this time, the part of the flexible sleeve that is used to directly contact and fit the inner cavity wall of the crystallization barrel is transformed into a part that has not undergone irreversible deformation, so the degree of contact and fit between the inner wall of the crystallization barrel, that is, the degree of scraping and interference with the barrel cavity wall, can be restored;

[0019] In order to facilitate the disassembly and installation of the rotating shaft together with the first cleaning part and the second cleaning part on the crystallization barrel, this solution does not lock the rotating shaft and the drive shaft, but installs a limiting bolt near the top of the rotating shaft to prevent the rotating shaft from floating up and separating from the drive shaft during rotation, thereby ensuring the effectiveness and synchronization of the rotating motor's transmission control of the rotating shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the appearance structure of a crystallization device for refining and preparing propacetamol hydrochloride according to the utility model;

[0021] Figure 2This is a schematic diagram of the internal structure of the crystallization device for refining and preparing propacetamol hydrochloride of the utility model (A-A cross-section view),

[0022] Figure 3 It is an exploded diagram of the connection structure between the various components of the cleaning part in the crystallization device for refining and preparing propacetamol hydrochloride of the utility model;

[0023] Figure 4 For attachment Figure 2 A front plan view of

[0024] Figure 5 For the attached Figure 4 A schematic diagram showing that after the rotating shaft is fully pulled upward away from the driving shaft by the handle, the rotating shaft is rotated so that the first cleaning part and the second cleaning part on the rotating shaft are upwardly close to the horizontal lower plate surface of the cover plate and are aligned one by one with the bar-shaped through grooves on the left and right sides of the cover plate from a perspective of ;

[0025] Figure 6 For the attached Figure 4 A schematic diagram of further pulling the rotating shaft vertically upward from the perspective of , so that the first cleaning part and the second cleaning part cooperate to pass through the corresponding strip-shaped through grooves and leave the crystallization barrel upward;

[0026] Figure 7 This is a schematic diagram showing the state of irreversible deformation of the long-term squeezed portion of the flexible sleeve when observed from the radial angle of the mounting rod and the flexible sleeve;

[0027] Figure 8 For the attached Figure 7 Based on the schematic diagram, the flexible sleeve is changed in angle and then coaxially fitted on the mounting rod again. At this time, the portion of the flexible sleeve that is used to directly contact and fit the inner cavity wall of the crystallization barrel is transformed into a portion that has not undergone irreversible deformation.

[0028] Among them, 10 is a crystallization barrel, 11 is a cooling coil, 14 is a threaded groove, 15 is a discharge hole,

[0029] 20—cover plate, 21—axis hole, 22—strip groove, 23—fixed seat, 231—threaded mounting hole, 24—limiting bolt, 25—threaded hole, 26—bolt, 27—feed hole,

[0030] 30—rotating shaft, 301—handle, 31—connecting rod, 32—installing rod, 321—limiting strip, 33—flexible sleeve, 331—embedded groove, 34—bump, 35—threaded connection hole,

[0031] 40—rotating motor, 41—driving shaft, 411—installation slot, 412—accommodation slot,

[0032] C—The position on the flexible sleeve that has been squeezed for a long time and has undergone irreversible deformation. DETAILED DESCRIPTION

[0033] It should be noted that the directional qualifiers "front", "rear", "left", "right", "horizontal", "vertical", etc. used in the description of the present invention, unless otherwise specified, refer to the direction of the attached Figure 4 , 5 , and 6, the directions "inside" and "outside" refer to the directions toward or away from the geometric center of a specific component, respectively. These are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0034] As attached Figure 1 , 2 As shown in , 4, the crystallization device for refining and preparing propacetamol hydrochloride of the utility model comprises a cylindrical crystallization barrel 10 with a vertical axis, a cooling coil 11 is evenly coiled inside the cylindrical vertical barrel plate of the crystallization barrel 10, a plurality of support legs are evenly distributed in annular directions at intervals near the circumference of the bottom of the crystallization barrel 10 to support the crystallization barrel 10 above the ground (not shown in the drawings), the top of the crystallization barrel 10 is open and is equipped with a cover plate 20 with a horizontal plate surface for covering the top opening of the crystallization barrel 10, and the cover plate 20 and the crystallization barrel 10 are coaxially arranged,

[0035] A number of threaded holes 25 are evenly distributed in the circumferential direction near the peripheral edge of the cover plate 20, and the axial direction is vertical and connected to the upper and lower plate surfaces of the cover plate 20. A threaded groove 14 is provided on the top edge of the crystallization barrel 10 corresponding to the threaded holes 25. The threaded groove 14 is formed by a local vertical downward depression on the top edge of the crystallization barrel 10. After the bolt 26 passes through the threaded hole 25 through the threaded hole 25, it is further threaded and fully screwed into the threaded groove 14 corresponding to the threaded hole 25, so that the cover plate 20 can be detachably matched and fixed to cover the crystallization barrel 10.

[0036] The cover plate 20 is provided with an axial hole 21 which is coaxially arranged with the cover plate 20 and connected with the upper and lower plate surfaces of the cover plate 20. A feed hole 27 which is vertically axially connected with the upper and lower plate surfaces of the cover plate 20 is provided on the cover plate 20 away from the axial hole 21. The feed hole 27 is connected downwardly to the barrel cavity of the crystallization barrel 10 as a whole.

[0037] A rotating shaft 30 is coaxially provided in the axial hole 21, and the rotating shaft 30 extends vertically downward into the barrel cavity of the crystallization barrel 10 along its own axial direction. A rotating motor 40 is fixedly installed at the bottom of the crystallization barrel 10, and a driving shaft 41 as the output end of the rotating motor 40 is vertically extended upward from the rotating motor 40. The driving shaft 41 is fixedly installed on the bottom plate of the crystallization barrel 10 through a bearing (not shown in the accompanying drawings) coaxially and can be axially rotatably sealed and extended into the barrel cavity of the crystallization barrel 10, as shown in the attached Figure 3As shown, the top of the driving shaft 41 is vertically depressed downward to form a mounting groove 411 which is coaxially arranged with the driving shaft 41 and for the rotating shaft 30 to be coaxially embedded therein. The top of the mounting groove 411 is partially vertically depressed downward to form a receiving groove 412. At a position on the shaft body of the rotating shaft 30 near the bottom end of the rotating shaft 30, a horizontal protrusion partially protrudes outward along the radial direction of the rotating shaft 30 to form a protrusion 34. While the rotating shaft 30 is vertically and coaxially embedded in the mounting groove 411, the protrusion 34 is vertically and coaxially embedded in the receiving groove 412, thereby realizing the coaxial transmission connection between the rotating shaft 30 and the driving shaft 41. The rotating motor 40 drives the rotating shaft 30 to rotate axially on the crystallization barrel 10 in turn through the driving shaft 41 and the protrusion 34. A discharge hole 15 with a vertical axis and connected to the upper and lower surfaces of the bottom plate of the crystallization barrel 10 is provided on the bottom plate of the crystallization barrel 10 away from the rotating motor 40. The discharge hole 15 is connected to the barrel cavity of the crystallization barrel 10 as a whole.

[0038] The portion of the rotating shaft 30 located in the barrel cavity of the crystallization barrel 10 is evenly distributed with three connecting rods 31 at intervals along the length direction of the rotating shaft 30. The connecting rods 31 are parallel to each other in the length direction. The connecting rods 31 are respectively formed by extending horizontally to the left along the radial direction of the rotating shaft 30 on the shaft body of the rotating shaft 30. Figure 3 As shown, the axially vertical mounting rod 32 is detachably fixed to the end of each connecting rod 31 away from the rotating shaft 30 in the length direction by cooperating with the bolts screwed into the corresponding threaded connection holes 35. The rod sections of the mounting rod 32 located between two adjacent connecting rods 31 are coaxially sleeved and tightly wrapped by flexible sleeves 33, respectively. The flexible sleeves 33 are made of rubber with smooth surface.

[0039] As attached Figure 3 As shown, the mounting rod 32 is located between two adjacent connecting rods 31 and protrudes horizontally to the right along the radial direction of the mounting rod 32 to form a limit strip 321 which is vertical in the length direction. The inner wall of the flexible sleeve 33 is evenly distributed with four vertical embedded grooves 331 in the length direction at intervals corresponding to the inner wall of the flexible sleeve 33. The embedded grooves 331 are connected to the upper and lower end surfaces of the flexible sleeve 33 along their own length direction. Each embedded groove 331 is formed by the inner wall of the flexible sleeve 33 being partially recessed horizontally outward along the radial direction of the flexible sleeve 33. The limit strip 321 is parallelly fitted and embedded in one of the embedded grooves 331 so as to be clamped by the flexible sleeve 33 to avoid relative axial rotation and slippage between the flexible sleeve 33 and the mounting rod 32 it wraps.

[0040] As attached Figure 1 , 2 As shown in Figure 4, with the support of each connecting rod 31 and the mounting rod 32, the flexible sleeve 33 is horizontally pressed against the inner wall of the crystallization barrel 10. When the rotating shaft 30 rotates axially on the crystallization barrel 10, the flexible sleeve 33 is driven by each connecting rod 31 and the mounting rod 32 in turn to contact and fit the inner wall of the crystallization barrel 10 and slide back and forth.

[0041] The connecting rods 31, the mounting rods 32, and the flexible sleeves 33 together form a first cleaning portion. A second cleaning portion extends horizontally to the right away from the first cleaning portion on the rotating shaft 30. The first cleaning portion and the second cleaning portion are symmetrically arranged with respect to each other based on the rotating shaft 30.

[0042] As attached Figure 1 , 2 As shown, corresponding to the first cleaning part and the second cleaning part, the cover plate 20 is provided with strip-shaped through grooves 22 on the left and right sides of the shaft hole 21, which are connected to the upper and lower plate surfaces of the cover plate 20 and are horizontally connected to the shaft hole 21, for the first cleaning part or the second cleaning part to vertically upwardly cooperate and pass through to leave the crystallization barrel 10. The horizontal shape of the strip-shaped through groove 22 is the shape of the first cleaning part or the second cleaning part vertically projected upward on the cover plate 20.

[0043] As attached Figure 1 , 4 As shown, the axial top end of the rotating shaft 30 extends vertically upward from the cover plate 20, and a handle 301 is fixedly connected to the top end of the rotating shaft 30. The cover plate 20 has fixing seats 23 extending vertically upward on both sides of the front and rear of the shaft hole 21, and each fixing seat 23 is provided with a threaded mounting hole 231 axially horizontal in the front-to-back direction. The threaded mounting holes 231 on the two fixing seats 23 are aligned front to back, and the limiting bolt 24 located directly above the rotating shaft 30 and close to the top end of the rotating shaft 30 is threadedly fitted and penetrated through the threaded mounting holes 231 of the two fixing seats 23.

[0044] In the present application, a flexible sleeve 33 made of rubber is coated on the mounting rod 32 near the side cavity wall in the inner cavity of the crystallization barrel 10. The flexible sleeve 33 contacts and fits the inner wall of the crystallization barrel 10 to slide relatively, so that the propacetamol hydrochloride crystal components attached to the inner wall of the crystallization barrel 10 during the crystallization process are scraped off in real time, so that this part of the crystals can smoothly enter the next process together with the materials in the barrel, thereby reducing the loss during the crystallization process; further, by making the limiting strip 321 on the mounting rod 32 parallel and fit into the embedded groove 331 on the inner wall of the flexible sleeve 33 and being clamped, relative axial rotation between the flexible sleeve 33 and the mounting rod 32 it wraps is avoided, thereby avoiding the flexible sleeve 33 from rolling and slipping on the inner wall of the crystallization barrel 10 during the scraping process, thereby reducing the scraping effect;

[0045] Compared with the use of hard scrapers, scrapers, etc. to contact and slide on the equally hard inner cavity wall of the crystallization barrel 10 in order to scrape off the crystals attached to the inner wall of the crystallization barrel 10, which is easy to produce harsh and unpleasant friction noise, and this hard friction is also easy to cause wear of parts, in this solution, only the flexible sleeve 33 made of rubber material is in contact with the inner cavity wall of the crystallization barrel 10, and under the support of each connecting rod 31 and the mounting rod 32, when the flexible sleeve 33 abuts against the inner cavity wall of the crystallization barrel 10, the flexible sleeve 33 is squeezed moderately and will not be squeezed too tightly, so that the sound generated when the flexible sleeve 33 contacts and fits on the inner wall of the crystallization barrel 10 and slides relatively to scrape off the crystals is greatly reduced, no obvious noise is emitted, and the production environment is purified;

[0046] In this solution, the connecting rod 31 not only supports and connects the mounting rod 32 and the flexible sleeve 33, but also stirs the material in the crystallization barrel 10 when the rotating shaft 30 rotates axially.

[0047] Moreover, when the rotating motor 40 stops running, the rotating shaft 30 together with the first cleaning part and the second cleaning part can be taken out from the crystallization barrel 10 as a whole through the axial hole 21 and the strip through groove 22 on the cover plate 20: after the rotating motor 40 stops running, the limiting bolt 24 is first removed from the two fixing seats 23, and the rotating shaft 30 is fully pulled upward from the driving shaft 41 through the handle 301, and then, with the first cleaning part and the second cleaning part upwardly pressed against the horizontal lower plate surface of the cover plate 20, the rotating shaft 30 is slightly rotated, so that the rotating shaft 30 is also matched in the axial hole 21 and axially rotated until the first cleaning part and the second cleaning part are aligned one by one with the strip through grooves 22 on the left and right sides of the cover plate 20 (as shown in the attached figure). Figure 5 ); further pull the rotating shaft 30 vertically upward, so that the first cleaning part and the second cleaning part respectively cooperate to pass through the corresponding strip-shaped through groove 22 to leave the crystallization barrel 10 and make contact with the crystallization barrel 10 for relative movement (such as the attached Figure 6 ), during this process, the lower edge of the shaft hole 21 on the cover plate 20 and the lower edge of the strip-shaped through groove 22 can also scrape a small amount of crystals attached to the surface of the rotating shaft 30 and the outer surface of the flexible sleeve 33 downward into the crystallization barrel 10, further reducing the loss during the crystallization process;

[0048] Considering that the flexible sleeve 33 in this solution is always pressed against the inner wall of the crystallization barrel 10 after being installed in the inner cavity of the crystallization barrel 10, although the degree of extrusion here is moderate, after long-term extrusion, irreversible deformation will still occur at the extruded part of the flexible sleeve 33 (such as the attached Figure 7), which causes the contact and fit between the flexible sleeve 33 and the inner wall of the crystallization barrel 10 to become loose, that is, the scraping interference degree of the flexible sleeve 33 on the inner wall surface of the crystallization barrel 10 during the rotation operation becomes smaller, which is not conducive to the scraping off of the crystals attached to the inner wall. In this regard, the present scheme provides a plurality of embedded grooves 331 at intervals in the circumferential direction on the inner cylinder wall of the flexible sleeve 33. After the rotating shaft 30 together with the first cleaning part and the second cleaning part are taken out from the barrel cavity through the operation in the previous paragraph, the mounting rod 32 is disassembled from each connecting rod 31, and the flexible sleeve 33 is removed from the mounting rod 32. After changing the angle, it is coaxially fitted on the mounting rod 32 again so that the limiting strip 321 on the mounting rod 32 is parallelly fitted and embedded in another embedded groove 331 and clamped (such as the attached Figure 8 ), and then install the mounting rod 32 onto the original connecting rods 31, and then install the rotating shaft 30 together with the first cleaning part and the second cleaning part into the barrel cavity in the original way (because the shaft hole 21 and the driving shaft 41 below and the mounting groove 411 thereon are always coaxially arranged in position, so when the rotating shaft 30 is coaxially matched in the shaft hole 21 and extends downward, it must always be coaxially aligned with the mounting groove 411, until the protrusion 34 abuts against the top edge of the driving shaft 41 downward, and then the rotating shaft 30 is axially rotated to align the protrusion 34 with the receiving groove 412, and then the protrusion 34 is further vertically downwardly matched and embedded in the receiving groove 412 through the rotating shaft 30, and the installation is completed), at this time, the part of the flexible sleeve 33 that is used to directly contact and fit the inner cavity wall of the crystallization barrel 10 is transformed into a part that has not undergone irreversible deformation, so the degree of contact and fit with the inner wall of the crystallization barrel 10, that is, the degree of scraping and interference with the barrel cavity wall, is restored;

[0049] In order to facilitate the disassembly and installation of the rotating shaft 30 together with the first cleaning part and the second cleaning part on the crystallization barrel 10, the present solution does not lock the rotating shaft 30 and the driving shaft 41, but the present solution installs a limiting bolt 24 near the top of the rotating shaft 30 to prevent the rotating shaft 30 from floating up and separating from the driving shaft 41 during the rotation operation, thereby ensuring the effectiveness and synchronization of the transmission control of the rotating shaft 30 by the rotating motor 40.

Claims

1. A crystallization device for refining and preparing propacetamol hydrochloride, characterized in that: The device comprises a cylindrical crystallization barrel (10) with a vertical axis, a cooling coil (11) distributed inside the body of the crystallization barrel (10), and a cover plate (20) with a horizontal surface for covering the top opening of the crystallization barrel (10) provided on the top of the crystallization barrel (10). The cover plate (20) is provided with an axial hole (21) communicating with the upper and lower plate surfaces of the cover plate (20), a rotating shaft (30) is coaxially passed through the axial hole (21), and the rotating shaft (30) extends vertically downward along its own axis into the barrel cavity of the crystallization barrel (10), A rotating motor (40) is fixedly mounted on the bottom of the crystallization barrel (10); a driving shaft (41) extending vertically upward from the rotating motor (40) can be axially rotatably sealed and extended into the barrel cavity of the crystallization barrel (10) and is transmission-connected to the axial bottom end of the rotating shaft (30); the rotating motor (40) drives the rotating shaft (30) to rotate axially on the crystallization barrel (10) through the driving shaft (41). The portion of the rotating shaft (30) located in the barrel cavity of the crystallization barrel (10) extends outward at intervals along the length direction of the rotating shaft (30) to form a plurality of connecting rods (31), each of which is parallel to the other in the length direction. An axially vertical mounting rod (32) is simultaneously fixed to one end of each of the connecting rods (31) which is away from the rotating shaft (30) in the length direction. The rod sections of the mounting rod (32) located between two adjacent connecting rods (31) are respectively coaxially sleeved and tightly wrapped by flexible sleeves (33), and the flexible sleeves (33) are horizontally outwardly pressed against the inner side wall of the crystallization barrel (10). When the rotating shaft (30) rotates axially on the crystallization barrel (10), the flexible sleeves (33) are driven by the connecting rods (31) and the mounting rods (32) in turn to contact and fit the inner side wall of the crystallization barrel (10) for reciprocating sliding.

2. The crystallization device for refining and preparing propacetamol hydrochloride according to claim 1, characterized in that: The mounting rod (32) is located between two adjacent connecting rods (31) and protrudes outwardly along the radial direction of the mounting rod (32) to form a limit strip (321) which is vertical in the length direction. The inner wall of the flexible sleeve (33) is evenly distributed with a plurality of vertical grooves (331) in the length direction at intervals in the circumferential direction. Each of the grooves (331) is formed by partially concavely extending the inner wall of the flexible sleeve (33) outwardly along the radial direction of the flexible sleeve (33). The limit strip (321) is parallelly fitted and embedded in one of the grooves (331) so as to be clamped by the flexible sleeve (33).

3. The crystallization device for refining and preparing propacetamol hydrochloride according to claim 1, characterized in that: The connecting rods (31), the mounting rods (32), and the flexible sleeves (33) together constitute a cleaning portion. The cover plate (20) is provided with a strip-shaped through groove (22) near the axial hole (21), which is connected to the upper and lower plate surfaces of the cover plate (20) and is connected to the axial hole (21) for the cleaning portion to vertically pass through. The strip-shaped through groove (22) is horizontally the shape of the cleaning portion projected vertically upward onto the cover plate (20).

4. The crystallization device for refining and preparing propacetamol hydrochloride according to claim 1, characterized in that: The top axial end of the rotating shaft (30) vertically extends upward from the cover plate (20), and fixing seats (23) are respectively vertically extended upward on the front and rear sides of the shaft hole (21) on the cover plate (20), and each fixing seat (23) is respectively provided with a threaded mounting hole (231), and a limiting bolt (24) located directly above the rotating shaft (30) and close to the rotating shaft (30) is simultaneously threadedly fitted into the threaded mounting holes (231) of the two fixing seats (23).

5. The crystallization device for refining and preparing propacetamol hydrochloride according to claim 1, characterized in that: The top of the driving shaft (41) is vertically recessed downward to form a mounting groove (411) for the rotating shaft (30) to be coaxially fitted and embedded in. The top of the mounting groove (411) is partially vertically recessed downward to form a receiving groove (412). At a position on the shaft body of the rotating shaft (30) close to the bottom end of the rotating shaft (30), a protrusion (34) is partially protruded outward along the radial direction of the rotating shaft (30). When the rotating shaft (30) is vertically and coaxially fitted into the mounting groove (411), the protrusion (34) is vertically and fitted into the receiving groove (412).

6. The crystallization device for refining and preparing propacetamol hydrochloride according to claim 1, characterized in that: A plurality of support legs are evenly distributed at intervals in the circumferential direction at the bottom of the crystallization barrel (10) near the circumference.

7. The crystallization device for refining and preparing propacetamol hydrochloride according to claim 1, characterized in that: The cover plate (20) is provided with a plurality of threaded holes (25) which are axially vertical and connected to the upper and lower plate surfaces of the cover plate (20) and are evenly distributed at intervals near the peripheral edge. The top edge of the crystallization barrel (10) is provided with threaded grooves (14) which correspond to the threaded holes (25) one by one. The threaded grooves (14) are formed by local vertical depressions on the top edge of the crystallization barrel (10). After the bolts (26) are threadedly fitted through the threaded holes (25), they are further threadedly fitted and fully screwed into the threaded grooves (14) corresponding to the threaded holes (25), so that the cover plate (20) is fixedly fitted to cover the crystallization barrel (10).

8. The crystallization device for refining and preparing propacetamol hydrochloride according to claim 1, characterized in that: A feed hole (27) with a vertical axis and connected to the upper and lower surfaces of the cover plate (20) is provided on the cover plate (20) away from the axial hole (21), and the feed hole (27) is connected downwardly to the barrel cavity of the crystallization barrel (10) as a whole.

9. The crystallization device for refining and preparing propacetamol hydrochloride according to claim 1, characterized in that: A discharge hole (15) with a vertical axis and connected to the upper and lower surfaces of the bottom plate of the crystallization barrel (10) is provided on the bottom plate of the crystallization barrel (10) away from the rotating motor (40), and the discharge hole (15) is connected to the barrel cavity of the crystallization barrel (10) upward as a whole.

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