Powder sieve and flour screening device comprising same
By designing a double-layer main screen, inclined screen surface, and vibrating block, combined with multi-stage screening and a fixed structure of mounting plate, the problems of low flour diffusion efficiency and poor grading effect in high-square flat screens are solved, achieving efficient screening and high-purity grading of flour.
Patent Information
- Application Number
- CN202511016289.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-23
- Publication Date
- 2025-11-18
AI Technical Summary
The existing high-square flat screen has low flour diffusion efficiency during the flour sieving process, resulting in reduced sieving efficiency and poor grading effect. In addition, the graded material contains the components of the next grade, which affects the quality and purity.
The system adopts a double-layer main screen design, combined with an inclined screen surface and vibrating blocks. The material screened by the main screen is diffused on the central plate and re-screened. The material that cannot pass through is further screened through the discharge channel. Multi-stage screening is carried out using secondary screen plates and auxiliary screens. Combined with the mounting plate and feed plate, the material is stably fixed and efficiently graded.
It improves the diffusion and sieving efficiency of flour, enhances the grading effect, increases the purity and sieving accuracy of flour, reduces the movement and diffusion time of materials on the sieve frame, and improves the overall sieving efficiency and accuracy.
Smart Images
Figure CN120961415A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of flour screening, and in particular to a powder sieve and a flour screening device containing the powder sieve. Background Technology
[0002] Flour screening mainly occurs in two production stages:
[0003] 1. After the flour is milled, it needs to be screened to remove the bran and impurities, and to separate the coarseness of the flour.
[0004] 2. Flour is screened before food processing, which usually involves emptying the flour from the flour bag for screening.
[0005] Flour screening equipment comes in various types, with large flour mills commonly using high-square flat screens. These screens use multiple vertically arranged sieve frames with mesh to sieve flour. High-square flat screens typically use a rotary diffusion mechanism, separating the flour falling onto the screen through rotation and diffusion. Because the flour falls in a concentrated area, the uniform diffusion efficiency is low, thus affecting the overall screening efficiency. Material trapped by the screen only exits after reaching the edge of the screen, resulting in low discharge efficiency for different grades of material. Furthermore, the trapped material may contain components from the next grade, leading to lower quality and purity of the final graded material. Summary of the Invention
[0006] In order to improve the shortcomings of flour sieving efficiency and poor flour grading effect caused by low flour diffusion efficiency when using a high-square flat sieve, this application provides a powder sieve and a flour screening device containing the powder sieve.
[0007] The powder sieve provided in this application adopts the following technical solution:
[0008] A powder sieve, comprising
[0009] Main frame;
[0010] The screen frame is installed at the top center of the main frame, and a discharge hole is formed between the two ends of the screen frame and the inner wall of the main frame. The main screen is installed on the upper surface of the screen frame.
[0011] A partition plate is fixed inside the discharge hole, dividing the discharge hole into two parts: the part closer to the screen frame is the receiving channel, and the part farther from the screen frame is the discharge channel.
[0012] The guide plate is fixed at the bottom of the partition plate and is inclined downwards near the center of the main frame.
[0013] The concentrator plate is installed inside the main frame and is fixedly connected to the bottom of the guide plate. A concentrator hole is opened in the middle position. The upper surface of the concentrator plate is inclined downward from the edge to the concentrator hole.
[0014] The main screen of the sieve frame also covers the receiving channel;
[0015] The secondary screen plate is detachably installed below the partition plate, and its bottom is attached to the inner side wall of the main frame;
[0016] The discharge hole is located on the side wall of the main frame and is connected to the discharge channel to allow the material on the secondary screen plate to be discharged.
[0017] By adopting the above technical solution, flour is poured onto a sieve frame. During the sieving process, the flour on the sieve frame continuously diffuses towards the downward feed holes. Flour that can pass through the main sieve falls onto the collection plate below. As the flour diffuses towards the downward feed holes, the flour falling from the main sieve above the receiving channel flows onto the collection plate. The flour on the collection plate is discharged through the collection holes or falls to the middle of the next main sieve frame, allowing the flour to diffuse from the center outwards, thus improving the efficiency of flour diffusion and sieving. Flour that cannot pass through the main sieve enters the secondary sieve plate through the discharge channel and is discharged through the discharge holes.
[0018] Optionally, main screens are distributed on both the upper and lower surfaces of the screen frame, and multiple vibrating blocks are placed between the main screens of the screen frame.
[0019] By adopting the above technical solution, the double-layer main screen of the sieve frame can effectively improve the sieving effect of flour. At the same time, the space formed provides a place for the vibrating block, and the swaying of the sieve frame drives the vibrating block to vibrate between the two main screens, thereby improving the efficiency of flour diffusion and sieving on the main screen.
[0020] Optionally, the upper surface of the screen frame is an inclined screen surface that slopes upward in the direction close to the partition plate. The upper surface of the partition plate and the plane containing the inclined screen surface are on the same plane. The main screen at the material receiving channel is parallel to the inclined screen surface.
[0021] By adopting the above technical solution, the inclined screen surface can provide diffusion resistance to flour that has not passed through the main screen at the edge, increase the screening time on the inclined screen surface, and because the centrifugal force and inertia generated by the vibration diffusion of larger particles of powder or material will be greater, larger particles of powder or material will be easier to pass through the inclined screen surface and enter the discharge channel, thus improving the flour screening effect.
[0022] Optionally, the angle between the inclined screen surface and the horizontal plane is an acute angle α, which is in the range of 4-10°.
[0023] By adopting the above technical solution, the inclined screen surface will have a better auxiliary screening effect within this angle range.
[0024] Optionally, a secondary screen hole is provided on the part of the secondary screen plate that is directly opposite the discharge channel, and an auxiliary screen is laid on the secondary screen hole. The auxiliary screen has the same mesh size as the main screen.
[0025] A feeding plate is provided at the bottom of the main frame. The feeding plate is located below the secondary screen plate and is inclined downward in the direction close to the center of the main frame, with its end located below the screen frame.
[0026] By adopting the above technical solution, the flour that falls onto the secondary sieve plate will be sieved again through the secondary sieve. The flour that can pass through the secondary sieve will fall onto the feed plate and, guided by the feed plate, fall onto the sieve frame of the next main frame for the next stage of sieving.
[0027] Optionally, a main strip plate can be detachably installed at the bottom of the guide plate, and multiple support plates are fixed on the main strip plate, with the top of the support plates abutting against the guide plate;
[0028] The bottom end of the partition plate is fixed with a slot, the circumferential side wall of the main frame is fixed with a protrusion below the discharge hole, and the bottom end of the secondary screen plate is provided with a groove for the protrusion to be inserted.
[0029] After the main plate is installed, the support plate is pressed against the bottom and side wall of the secondary screen plate. At this time, the top of the secondary screen plate is pressed against the slot, and the inner wall of the groove is pressed against the protrusion.
[0030] The feed plate can be detachably mounted on the support plate;
[0031] A secondary strip plate is fixed to the top of the support plate, and the secondary screen plate can be detachably installed on the secondary strip plate.
[0032] By adopting the above technical solution, the main strip plate is installed below the guide plate, thereby realizing the installation of multiple support plates. The secondary screen plate is then pressed against the main frame by the multiple support plates, thus achieving the detachable installation of the secondary screen plate.
[0033] This application also provides a flour screening device with the following technical solution:
[0034] A flour screening device includes the aforementioned flour sieve, and further includes...
[0035] The flat screen machine body has a screen chamber on the side wall, which is used to place multiple main frames stacked on top of each other. The opening of the screen chamber is equipped with a door to press the main frames tightly inside the screen chamber. The material discharge port is located in the middle of the top of the screen chamber.
[0036] When the main frame is inside the screen chamber, the discharge hole faces the side wall of the screen chamber;
[0037] Multiple mounting plates are fixed on the side wall of the screen chamber. The mounting plates are located inside the discharge hole and fit against the inner wall of the discharge hole. Multiple discharge pipes are installed inside the flat screen machine body. The bottom end of the discharge pipe extends from the bottom of the flat screen machine body, and the top end is installed on the mounting plate. The mounting plate has through holes that allow the discharge pipe to communicate with the discharge channel.
[0038] The through holes of the mounting plates at both ends of the main frame with the same mesh size are opposite each other, and the discharge pipes connected to the mounting plates with the same through hole position at the same end of the main frame are interconnected.
[0039] The bottom of the screen chamber is connected to the main material pipe, and the top of the main material pipe is opposite to the central hole of the main frame above.
[0040] By adopting the above technical solution, multiple main frames are stacked one on top of the other and inserted into the sieve chamber. This not only allows for the clamping and fixing of the main frames through the sieve chamber, but also enhances the stability of the main frames by positioning the mounting plate within the discharge hole. Furthermore, the through holes in the mounting plate allow material in the discharge channel to be conveyed to the discharge pipe, achieving graded discharge of the flour after screening. The discharge pipes corresponding to main frames with the same screening capacity are interconnected, allowing for simultaneous discharge and making the internal layout of the flat sieve machine more rational.
[0041] Optionally, multiple main frames are grouped together, and the main frames in a group are installed vertically adjacent to each other, with the main screen mesh count of the multiple main frames in a group being the same;
[0042] In a group of multiple main frames, except for the bottom main frame, the secondary screen plates in the other main frames will be removed, and the through holes of the mounting plates corresponding to the main frames that do not contain secondary screen plates will be sealed.
[0043] By adopting the above technical solution, materials with the same requirements can be screened using a set of main frames. By disassembling the secondary screen plates, materials that fail to pass through the main screen fall into a guide plate in the discharge channel, and then onto the edge of the next main frame for further screening. Because the materials fall into the edge, the re-screening path and time are shorter, resulting in higher efficiency and improved accuracy and efficiency of material screening.
[0044] Optionally, the bottom sides of the main frame are provided with snap-in slots for the top of the main frame below to be inserted into, and the side wall of the snap-in slot is directly opposite the closed compartment door.
[0045] By adopting the above technical solution, the design of the slot can ensure that the position of multiple main frames is more stable after they are stacked and inserted into the screen chamber. That is, the main frames can only be separated when multiple main frames are taken out of the screen chamber together.
[0046] In summary, this application includes at least one of the following beneficial technical effects:
[0047] 1. Flour and other materials fall into the middle of the sieve frame and move towards the lower feed hole through vibration. During this process, the material passing through the main sieve falls onto the lower concentrating plate. The inclined screen surface of the main sieve effectively increases the time for materials that have not yet passed through the main sieve to move towards the discharge channel. Larger particles have greater inertia and pass through faster, allowing for further screening of materials that can pass through the main sieve at the receiving channel. The material falling onto the lower concentrating plate falls into the middle of the lower sieve frame through the concentrating holes for screening, improving the efficiency of screening and diffusion of flour and other materials.
[0048] 2. The material entering the secondary screen plate from the discharge channel will be further screened on the secondary screen. The material that can pass through the secondary screen will fall onto the feed plate and then fall onto the edge of the screen frame below. This not only improves the accuracy of screening materials such as flour, but also improves the screening efficiency. The material that cannot pass through the secondary screen will be discharged from the discharge hole.
[0049] 3. The secondary screen plate can be installed and removed as needed. Only the secondary screen plate of the bottom main frame is retained in the group of main frames. The material entering the discharge channel will fall directly onto the feed plate and then fall onto the edge of the next screen frame for secondary screening. The material drop point setting on the feed plate can reduce the movement and diffusion time of the material on the screen frame, and secondary screening is only carried out near the inclined screen surface, which improves the accuracy and efficiency of screening. Attached Figure Description
[0050] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of this application;
[0051] Figure 2 This is a partial exploded view of the screening chamber shown in Embodiment 1 of this application;
[0052] Figure 3 This is a partial sectional view of the main frame installation position shown in Embodiment 1 of this application;
[0053] Figure 4 This is a schematic diagram of the structure of the main frame after the main screen and the secondary screen are hidden in Embodiment 1 of this application;
[0054] Figure 5 This is a partial cross-sectional view of the main screen and the auxiliary screen shown in Embodiment 1 of this application;
[0055] Figure 6 This is a schematic diagram showing the material movement path after the main screen and auxiliary screen are hidden in Embodiment 1 of this application;
[0056] Figure 7 This is a partial cross-sectional view showing the angle of the inclined screen surface in Embodiment 1 of this application;
[0057] Figure 8This is a partial exploded view of the installation components after the main screen and the auxiliary screen are hidden in Embodiment 1 of this application;
[0058] Figure 9 This is a partial cross-sectional view showing the location of the discharge pipe assembly in Embodiment 1 of this application;
[0059] Figure 10 This is a partial cross-sectional view of Embodiment 2 of this application, showing the installation state of the secondary sieve plates of multiple main frames.
[0060] In the diagram, 1. Main frame; 11. Feeding hole; 111. Receiving channel; 112. Discharge channel; 12. Discharge hole; 121. Protrusion; 13. Feeding plate; 14. Insertion groove; 2. Screen frame; 21. Inclined screen surface; 22. Main screen; 23. Vibrating block; 3. Divider plate; 31. Guide plate; 32. Concentrating plate; 321. Concentrating hole; 322. Center hole; 33. Slot; 4. Secondary screen plate; 41. Secondary screen; 42. Secondary screen hole; 5. Mounting components; 51. Main strip plate; 52. Support plate; 53. Secondary strip plate; 6. Flat screen machine body; 61. Screen bin; 62. Bin door; 63. Mounting plate; 631. Through hole; 632. Discharge pipe; 64. Main material pipe. Detailed Implementation
[0061] The following is in conjunction with the appendix Figure 1-10 This application will be described in further detail.
[0062] This application discloses a powder sieve and a flour screening device containing the powder sieve.
[0063] Example 1
[0064] refer to Figure 1 and Figure 2 The flour screening device includes a flat sieve body 6 and a powder sieve. The flat sieve body 6 contains a vibrating motor for rotary vibration. Multiple sieve chambers 61 are provided on the side wall of the flat sieve body 6, allowing multiple powder sieves to be stacked vertically. A door 62 is installed at the opening of each sieve chamber 61; when closed, the sieves are pressed and secured. The discharge port is located at the center of the top of each sieve chamber 61 for discharging flour and other materials.
[0065] Combination Figure 3 The bottom of the screening chamber 61 is connected to the main material pipe 64, which is used to collect materials such as flour that have passed through the powder screen. The flat screen machine body 6 is equipped with multiple discharge pipes 632, which are used to collect the multi-stage materials screened out by the powder screen.
[0066] refer to Figure 4 and Figure 5The powder sieve includes a main frame 1, a sieve frame 2, a partition plate 3, and a secondary sieve plate 4. The sieve frame 2 is installed at the top center of the main frame 1, forming a discharge hole 11 between the two ends of the sieve frame 2 and the inner wall of the main frame 1. The partition plate 3 is vertically installed and fixed to the inner wall of the discharge hole 11, dividing the discharge hole 11 into two parts: the part closer to the sieve frame 2 is the receiving channel 111, and the part farther from the sieve frame 2 is the discharge channel 112. A guide plate 31 is fixedly installed at the bottom of the partition plate 3, and the guide plate 31 is inclined downwards towards the center of the main frame 1. The same concentrating plate 32 is fixedly installed at the bottom of both guide plates 31, and the side wall of the concentrating plate 32 is fixedly connected to the sieve frame 2. A concentrating hole 321 is opened in the middle of the concentrating plate 32, and the upper surface of the concentrating plate 32 is inclined downwards from the edge to the concentrating hole 321. Multiple center holes 322 are also opened on the concentrating plate 32. The concentrating plate 32, the guide plate 31, and the partition plate 3 are welded together to form a whole, and then welded to the main frame 1. The screen frame 2 is placed inside the main frame 1 and then fastened to the main frame 1 with bolts.
[0067] Combination Figure 6 and Figure 7 The upper and lower surfaces of the screen frame 2 are both equipped with main screens 22, which are stretched and nailed to the screen frame 2. Multiple vibrating blocks 23 are placed in the space between the upper and lower main screens 22 of the screen frame 2. The main screens 22 of the screen frame 2 also cover the receiving channel 111. A discharge hole 12 communicating with the discharge channel 112 is also provided on the side wall of the main frame 1. The upper end of the screen frame 2 is an inclined screen surface 21 that slopes upwards near the partition plate 3. The upper surface of the partition plate 3 and the plane containing the inclined screen surface 21 are on the same plane. The main screen 22 at the receiving channel 111 is parallel to the inclined screen surface 21. The angle α between the inclined screen surface 21 and the horizontal plane is acute, ranging from 4 to 10°. In this embodiment, the angle α is 6°, with an allowable error within ±1°.
[0068] Combination Figure 6 After flour and other materials fall into the middle of the screen frame 2, they spread outwards from the screen frame 2 due to the vibration of the flat screen machine body 6. Materials that can pass through the main screen 22 fall onto the lower concentrator plate 32, while those that fail to pass through the main screen 22 move to the inclined screen surface 21 and, under vibration, move along the inclined screen surface 21 towards the discharge channel 112. Under the influence of inertia and centrifugal force, larger particles move more efficiently towards the discharge channel 112. The inclined screen surface 21 provides resistance to material movement through its tilt angle, thereby increasing the filtration time of materials that have not yet passed through the main screen 22 at the receiving channel 111, allowing materials that can pass through the main screen 22 to fall from the receiving channel 111 onto the guide plate 31. The tilt angle of the inclined screen surface 21 should not be too large; excessive tilt will prevent materials from moving to the receiving channel 111, while too small an tilt angle will reduce the material screening effect.
[0069] Material falling onto the guide plate 31 flows towards the concentrating plate 32 and then towards the concentrating hole 321. During this process, some material falls through the center hole 322 to the next screen frame 2 for screening, while the remaining material falls through the concentrating hole 321 to the middle of the lower screen frame 2 for the next stage of screening, ensuring that the material diffuses from the center of the screen plate. The center hole 322 reduces the distance that some material travels, improving screening efficiency and the utilization rate of the main screen area 22. The vibrating block 23, through inertia, increases the vibration amplitude of the main screen 22 in the corresponding area, improving the screening efficiency of the material in that area and reducing the probability of clogging the main screen 22.
[0070] refer to Figure 7 and Figure 8 The secondary screen plate 4 is detachably installed below the partition plate 3. The partition plate 3 has a slot 33 at its bottom, and a protrusion 121 is fixed on the circumferential side wall of the main frame 1 below the discharge hole 12. The guide plate 31 has an installation component 5 at its bottom, which is used to install the secondary screen plate 4. After installation, the top of the secondary screen plate 4 is inserted into the slot 33, the bottom is inclined and the end part has a groove, and the protrusion 121 is embedded in the groove at the bottom of the secondary screen plate 4. The lowest point of the plane at the bottom of the secondary screen plate 4 is higher than the inner bottom wall of the discharge hole 12. The bottom of the secondary screen plate 4 is inclined downward in the direction away from the center of the screen frame 2 to facilitate the movement of the material at the bottom of the secondary screen plate 4 to the discharge hole 12 under vibration. The part of the secondary screen plate 4 opposite to the discharge channel 112 has a secondary screen hole 42, and a secondary screen 41 is laid on the secondary screen hole 42. The secondary screen 41 has the same mesh size as the main screen 22. A feed plate 13 is provided at the bottom of the main frame 1. The feed plate 13 is located below the secondary screen plate 4 and is inclined downward in the direction close to the center of the main frame 1, with its end located below the screen frame 2. The feed plate 13 is installed by the mounting assembly 5.
[0071] When the main frame 1 is installed inside the screen chamber 61, the discharge hole 12 faces the inner wall of the screen chamber 61. Multiple mounting plates 63 are fixed to the side wall of the screen chamber 61, and the mounting plates 63 are located inside the discharge hole 12 and fit against the inner wall of the discharge hole 12. The bottom end of the discharge pipe 632 extends from the bottom of the flat screen body 6, and the top end is mounted on the mounting plate 63. The mounting plate 63 has a through hole 631 that connects the discharge pipe 632 to the discharge channel 112. After the main frame 1 is installed, the lowest point of the upper surface of the bottom part of the secondary screen plate 4 is not lower than the position of the bottom wall inside the through hole 631. The through holes 631 of the mounting plates 63 at both ends of the main frame 1 with the same mesh size of the main screen 22 are opposite each other, and the discharge pipes 632 connected to the mounting plates 63 with the same through hole 631 position at the same end of the main frame 1 are interconnected. The top end of the main material pipe 64 is opposite to the central hole 321 of the upper main frame 1. The inner bottom wall of the screen chamber 61 slopes downwards from all sides towards the main material pipe 64. The bottom sides of the main frame 1 are provided with slots 14 for the top of the lower main frame 1 to be inserted. The side wall of the slot 14 is directly opposite the closed door 62. When the two main frames 1 are stacked together, the upper surface of the lower main frame 1 is pressed and sealed by the upper main frame 1.
[0072] Material that fails to pass through the main screen 22 after passing through the inclined screen 21 falls into the discharge channel 112 and onto the bottom of the secondary screen plate 4, where it undergoes further screening on the auxiliary screen 41. Material that fails to pass through the auxiliary screen 41 moves through the through hole 631 into the discharge pipe 632 and is discharged from the screen chamber 61. The discharge pipes 632 corresponding to the main frames 1 with the same mesh size of the main screen 22 are interconnected, making full use of the space inside the flat screen machine body 6 and connecting the discharge pipes 632 that discharge materials of the same specifications to reduce the occupation of vertical space. Material that passes through the auxiliary screen 41 falls onto the feed plate 13 and flows onto the next screen frame 2. Due to the position of the feed plate 13 at its end, the vibrating screening distance of the material falling from the feed plate 13 to the lower screen frame 2 is small, and the amount of material left on the feed plate 13 is also small, thus improving the screening efficiency of this part of the material. This design can effectively improve the accuracy of sieving materials such as flour.
[0073] Multiple main frames 1 are stacked together, with the lower main frame 1 snapping into the slot 14 of the upper main frame 1, and the mounting plate 63 positioned within the discharge hole 12, thus achieving stable fixation of the main frame 1. The slot 14, together with the mounting plate 63, not only enhances the firmness of the main frame 1 fixation but also allows for individual removal of a single main frame 1 only after the stack of main frames 1 has been removed together, reducing the probability of material spillage when a single main frame 1 is removed and improving the purity of the collected material. The mounting frame not only ensures stable fixation of the main frame 1 but also guides materials of different screening degrees to different discharge pipes 632, improving the rationality of the structural design.
[0074] refer to Figure 8 and Figure 9 The mounting assembly 5 includes a main strip 51, a support plate 52, and a secondary strip 53. The main strip 51 is detachably mounted on the bottom of the guide plate 31. The main strip 51 can be installed using fasteners or nails; in this embodiment, it is fixed with bolts. Multiple support plates 52 are fixed to the main strip 51. The top of the support plate 52 abuts against the bottom of the guide plate 31, and the sidewall of the support plate 52 abuts against the inner sidewall of the main frame 1. After the main strip 51 is installed, the support plate 52 abuts against the bottom and sidewall of the secondary screen plate 4, and also abuts the secondary screen plate 4 against the support plate 52 and the inner sidewall of the main frame 1. The secondary strip 53 is fixed to the top of the secondary screen plate 4, and the secondary screen frame 2 is detachably mounted on the secondary strip 53. The detachable installation of the secondary screen plate 4 and the secondary strip 53 can be achieved using fasteners or nails; in this embodiment, it is fixed with bolts. The secondary screen plate 4 can be pre-installed on the secondary strip plate 53, and then fixed by the installation of the main strip plate 51. The feed plate 13 is detachably installed on the support plate 52. The detachable installation method can be by fastening with fasteners or nailing, and in this embodiment, it is fixed by bolts. After installation, the upper surface of the feed plate 13 is in contact with the lower surface of the support plate 52. The inner sidewall of the main frame 1 has a slot for inserting the end of the feed plate 13 into the slot. After the feed plate 13 is inserted into the slot, it is fixed to the support plate 52 by bolts.
[0075] The support plate 52 is fixed to the guide plate 31 via the main strip plate 51, and also fixes the secondary screen plate 4, improving the stability of the secondary screen plate 4 and enabling its disassembly and replacement. The feed plate 13 utilizes the structure of the support plate 52 for its own installation and fixation, and uses a slot structure to further enhance its stability. The frame structure formed by the support plate 52, main strip plate 51, and secondary strip plate 53 also improves its strength, thereby enhancing its vibration resistance.
[0076] The implementation principle of Embodiment 1 of this application is as follows: Flour and other materials fall onto the screen frame 2 through the discharge port at the top of the screen chamber 61. Under the vibration of the flat screen body 6, the material continuously diffuses on the main screen 22 and moves towards the discharge channel 112. Material that has not yet passed through the main screen 22 will gather on the inclined screen surface 21. Under the action of the inclined screen surface 21, the diffusion speed of the material slows down. Larger particles and heavier materials generate greater inertia under vibration, thus passing through the inclined screen surface 21 more quickly and entering the discharge channel 112. The inclined screen surface 21 also allows for further screening of the material using the receiving channel 111 by slowing down the material movement.
[0077] Material passing through the main screen 22 falls through the concentrator plate 32 to the middle of the next screen frame 2 for further screening. Material entering the discharge channel 112 undergoes final screening on the secondary screen plate 4. Material that cannot pass through the auxiliary screen 41 is discharged directly through the material holes into the discharge pipe 632. Material passing through the auxiliary screen 41 falls onto the feed plate 13 and flows to the edge of the next screen frame 2 for further screening. This arrangement of the main frame 1 allows material to diffuse evenly from the center to both sides, improving material diffusion efficiency and thus screening efficiency. Multi-step screening also improves the purity of the screened material. The mounting plate 63 structure also allows for the fixing of the main frame 1 and the grading and classification of discharged materials.
[0078] Example 2
[0079] refer to Figure 10 The difference between Embodiment 2 and Embodiment 1 is that: multiple main frames 1 are grouped together, and the main frames 1 within a group are installed vertically adjacent to each other, and the mesh count of the main screen 22 is the same. In the group of main frames 1, except for the bottommost main frame 1, the secondary screen plate 4 is removed from all other main frames 1. The mounting plate 63 corresponding to the main frame 1 that does not contain the secondary screen plate 4 closes the through hole 631.
[0080] The implementation principle of Embodiment 2 differs from that of Embodiment 1 in that: the main frame 1 is grouped, and the material entering the discharge channel 112 is screened again by removing the secondary screen plate 4, so that the material falls directly from the discharge channel 112 onto the feed plate 13, and then onto the edge of the next screen frame 2. This further screens the material passing through the discharge channel 112 at the edge of the next screen frame 2, reducing the path length of this part of the material on the screen frame 2. The secondary screen is mainly screened using the inclined screen surface 21 of the next screen frame 2. This is used for grading and screening materials such as flour with small particle size differences. The detachable secondary screen plate 4 also facilitates adjustment according to screening requirements.
[0081] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.
Claims
1. A powder sieve, characterized in that: include Main frame (1); The screen frame (2) is installed at the top middle position of the main frame (1), and a discharge hole (11) is formed between the two ends of the screen frame (2) and the inner wall of the main frame (1). The main screen (22) is installed on the upper surface of the screen frame (2). The partition plate (3) is fixed in the discharge hole (11) and divides the discharge hole (11) into two parts, the part closer to the screen frame (2) is the receiving channel (111) and the part farther away from the screen frame (2) is the discharge channel (112). The guide plate (31) is fixed at the bottom of the partition plate (3) and is inclined downward in the direction close to the center of the main frame (1); A concentrating plate (32) is installed inside the main frame (1) and is fixedly connected to the bottom end of the guide plate (31). A concentrating hole (321) is opened in the middle position. The upper surface of the concentrating plate (32) is inclined downward from the edge to the concentrating hole (321). The main screen (22) of the screen frame (2) also covers the receiving channel (111); The secondary screen plate (4) is detachably installed below the partition plate (3), and its bottom is attached to the inner wall of the main frame (1); The discharge hole (12) is located on the side wall of the main frame (1) and is connected to the discharge channel (112) to discharge the material on the secondary screen plate (4).
2. The powder sieve according to claim 1, characterized in that: The upper and lower surfaces of the sieve frame (2) are both covered with main screens (22), and multiple vibrating blocks (23) are placed between the main screens (22) of the sieve frame (2).
3. The powder sieve according to claim 1, characterized in that: The upper end of the screen frame (2) is an inclined screen surface (21) that is inclined upward in the direction close to the partition plate (3). The upper surface of the partition plate (3) and the plane where the inclined screen surface (21) is located are the same plane. The main screen (22) at the material receiving channel (111) is parallel to the inclined screen surface (21).
4. A powder sieve according to claim 3, characterized in that: The angle between the inclined sieve surface (21) and the horizontal plane is an acute angle α, which is in the range of 4-10°.
5. A powder sieve according to claim 1, characterized in that: The secondary screen plate (4) is provided with secondary screen holes (42) in the part directly opposite to the discharge channel (112). A secondary screen (41) is laid on the secondary screen holes (42). The secondary screen (41) has the same mesh number as the main screen (22). A feeding plate (13) is provided at the bottom of the main frame (1). The feeding plate (13) is located below the secondary screen plate (4) and is inclined downward in the direction close to the center of the main frame (1). Its end is located below the screen frame (2).
6. A powder sieve according to claim 5, characterized in that: The bottom of the guide plate (31) is detachably equipped with a main strip plate (51), and the main strip plate (51) is fixed with multiple support plates (52), the top of the support plates (52) abutting against the guide plate (31); The bottom end of the partition plate (3) is fixed with a slot (33), the circumferential side wall of the main frame (1) is fixed with a protrusion (121) below the discharge hole (12), and the bottom end of the secondary screen plate (4) is provided with a groove for the protrusion (121) to be inserted. After the main strip (51) is installed, the support plate (52) abuts against the bottom and side wall of the secondary screen plate (4). At this time, the top of the secondary screen plate (4) abuts against the slot (33), and the inner wall of the groove abuts against the protrusion (121). The feed plate (13) is detachably mounted on the support plate (52).
7. A powder sieve according to claim 6, characterized in that: A secondary strip plate (53) is fixedly installed on the top of the support plate (52), and the secondary screen plate (4) is detachably installed on the secondary strip plate (53).
8. A flour screening device, comprising the flour sieve according to any one of claims 5-7, characterized in that: Also includes The flat screen machine body (6) has a screen chamber (61) on its side wall. The screen chamber (61) is for multiple main frames (1) to be stacked up and down. The opening of the screen chamber (61) is equipped with a door (62) to press the main frames (1) tightly inside the screen chamber (61). The top middle position of the screen chamber (61) is the discharge port. When the main frame (1) is inside the screen chamber (61), the discharge hole (12) faces the side wall of the screen chamber (61); Multiple mounting plates (63) are fixedly installed on the side wall of the screen chamber (61). The mounting plates (63) are located inside the discharge hole (12) and fit against the inner wall of the discharge hole (12). Multiple discharge pipes (632) are installed inside the flat screen machine body (6). The bottom end of the discharge pipe (632) extends out from the bottom of the flat screen machine body (6) and the top end is installed on the mounting plate (63). The mounting plate (63) has a through hole (631) that connects the discharge pipe (632) with the discharge channel (112). The through holes (631) of the mounting plates (63) at both ends of the main frame (1) with the same mesh number of the main screen (22) are opposite to each other, and the discharge pipes (632) connected to the mounting plates (63) with the same through holes (631) at the same end of the main frame (1) are interconnected. The bottom of the screen bin (61) is connected to the main material pipe (64), and the top of the main material pipe (64) is opposite to the central hole (321) of the upper main frame (1).
9. A flour screening device according to claim 8, characterized in that: Multiple main frames (1) are grouped together. After installation, multiple main frames (1) in a group are adjacent to each other. The main screen (22) of multiple main frames (1) in a group has the same mesh number. In a group of multiple main frames (1), except for the bottom main frame (1), the secondary screen plate (4) is removed in all other main frames (1), and the mounting plate (63) corresponding to the main frame (1) without the secondary screen plate (4) closes the through hole (631).
10. A flour screening device according to claim 8, characterized in that: The bottom sides of the main frame (1) are provided with slots (14) for the top of the main frame (1) below to be inserted. The side wall of the slot (14) is directly opposite the closed door (62).