A tea sieving device

Abstract

This utility model discloses a tea sieving device, which relates to the field of tea processing equipment. The device includes: a frame; a sieving drum mounted on the frame, capable of rotating axially to convey tea leaves; multiple grading sieve segments arranged sequentially along the axial direction on the sieving drum, each grading sieve segment including multiple sieve holes on the drum, the sieve hole diameter increasing sequentially from the front to the back; and a movable partition installed inside the sieving drum, the outer contour of which matches the inner contour of the drum, dividing the drum into a main sieving section and a pre-sieving section. This ensures sufficient contact between the tea leaves and the sieve mesh, achieving precise sieving of different grades of tea leaves and improving grading efficiency and purity.

Description

Technical Field

[0001] This utility model relates to the field of tea processing equipment, specifically to a tea sieving device. Background Technology

[0002] A tea sieving machine is a device used in tea processing to separate tea particles of different sizes by utilizing the difference in mesh size. Through mechanical vibration, rotation, or airflow, the tea leaves move rhythmically on the sieve surface, achieving precise separation of particles of varying sizes, weights, and shapes. The core value of tea sieving lies in achieving multi-dimensional optimization of quality, processing, and market through the precise separation of tea particles of different sizes. The uniform particles after sieving undergo more even oxidation during fermentation and roasting, avoiding over-fermentation caused by particle differences, reducing mechanical wear, and improving processing efficiency.

[0003] A tea drum sieving machine, disclosed according to authorization announcement number (CN113926686B), includes a screen, cutters, a dust cover, a first motor, and a frame. The screen is cylindrical and mounted on the frame with its feed end inclined upwards and its shaft rotatable. The diameter of the screen holes gradually increases. In use, the tea leaves move along the screen's axis from the feed end to the other end of the screen. The smaller screen hole sections near the feed end, with smaller diameters and longer lengths, can more completely remove tea fragments, while subsequent screen holes grade the tea leaves.

[0004] The structure disclosed in this patent has defects in practical applications, specifically as follows: When tea leaves continuously move on the sieve, if the amount of tea leaves is large, they tend to accumulate on the sieve surface, preventing the bottom layer of tea leaves from making sufficient contact with the sieve and thus hindering effective sieving. Especially when the sieve openings are small, the accumulated tea leaves can obstruct the fall of fine particles. Furthermore, when the accumulated tea leaves move with the sieve to areas with larger openings, tea particles of different sizes may pass through the openings simultaneously, ultimately resulting in tea of ​​different specifications being mixed into tea of ​​the same grade, affecting the accuracy of grading. Utility Model Content

[0005] The purpose of this utility model is to provide a tea sieving device that addresses the problems in the existing technology where tea accumulation leads to insufficient contact between the sieve and the grading accuracy, resulting in the easy mixing of different grades of tea. This device ensures that the tea leaves are in full contact with the sieve, achieving accurate sieving of different grades of tea leaves and improving grading efficiency and purity.

[0006] This utility model is achieved through the following technical solution:

[0007] A tea sieving device includes: a frame; a sieving drum mounted on the frame, capable of rotating axially to convey tea leaves inside; multiple grading sieve segments sequentially arranged axially on the sieving drum, each grading sieve segment including multiple sieve holes on the sieving drum, the sieve hole diameter of the multiple grading sieve segments increasing sequentially from the front to the rear; a movable partition mounted inside the sieving drum, the outer contour of the movable partition matching the inner contour of the sieving drum, the movable partition capable of dividing the sieving drum into a main sieving zone and a pre-sieving zone; and a drive assembly mounted on the frame, capable of driving the movable partition to move axially along the sieving drum, thereby controlling the preset grading sieve segments to enter the main sieving zone.

[0008] Furthermore, in this utility model, the aforementioned drive assembly includes a first motor, a transmission shaft, and a guide shaft; the first motor is mounted on the frame, and the output end of the first motor is connected to the transmission shaft; the transmission shaft is coaxially arranged with the movable partition, the transmission shaft passes through the movable partition, and the transmission shaft and the movable partition are threaded together; one end of the guide shaft is connected to the frame, and the other end of the guide shaft passes through the movable partition.

[0009] Furthermore, in this utility model, the outer periphery of the aforementioned movable partition is provided with multiple assembly channels along the circumferential direction, and cleaning components are installed in the assembly channels.

[0010] Furthermore, in this utility model, the cleaning component includes an elastic element and a cleaning scraper; one end of the elastic element is connected to the bottom wall of the assembly channel, and the other end of the elastic element is connected to the cleaning scraper; one end of the cleaning scraper is guided and engaged with the assembly channel, and the other end of the cleaning scraper can abut against the inner wall of the screening drum.

[0011] Furthermore, in this invention, the end of the cleaning scraper facing the inner wall of the screening drum is an arc-shaped surface, which can fit against the inner wall of the screening drum.

[0012] Furthermore, in this utility model, the above also includes a feeding hopper, which is installed on the frame. One end of the feeding hopper is a funnel-shaped main feed inlet, and the other end of the feeding hopper is a screening feed inlet that extends into the screening drum.

[0013] Furthermore, in this utility model, the screening drum is provided with an impurity separation section on the side near the feed hopper, and the impurity separation section includes a plurality of impurity removal holes provided on the screening drum.

[0014] Furthermore, in this utility model, the above also includes a rolling support assembly, and multiple rolling support assemblies are installed on the frame; the rolling support assembly includes a mounting frame and rollers arranged on both sides of the screening drum, the bottom of the mounting frame is installed on the frame, and the top of the mounting frame is rotatably mounted on the rollers, which roll and abut against the screening drum.

[0015] Furthermore, in this utility model, the above also includes a transmission assembly, which includes a second motor, a transmission gear, and a gear ring; the second motor is mounted on the frame, and the output end of the second motor is connected to the transmission gear; the gear ring is fitted on the outside of the screening drum, and the gear ring meshes with the transmission gear.

[0016] Compared with the prior art, this utility model has the following advantages and beneficial effects:

[0017] 1. This application controls the movable baffle to move axially along the screening drum via a drive component, opening the grading screening sections in stages (e.g., initially only the first screening section is opened, and after the tea leaves of that grade are screened, the subsequent second and third screening sections are opened sequentially), allowing the tea leaves to gradually expand from small to large within the screening drum. Compared to the accumulation problem caused by tea leaves entering the entire screening section at once in the prior art, this structure can precisely match the tea leaf processing volume and screen aperture area of ​​each screening section, avoiding overload accumulation of material in a single area and ensuring that the bottom layer of tea leaves can fully contact the screen apertures; at the same time, through the "screening-isolation-rescreening" mode, the tea leaves pass through the grading screening sections with increasing apertures sequentially, completing the corresponding particle size screening within each grading screening section.

[0018] 2. In this application, the movable partition divides the interior of the screening drum into a main screening zone and a pre-screening zone. Tea leaves are only screened for their current grade within the main screening zone, while the screening sections in the pre-screening zone are not used. This "precise isolation and segmented processing" mode reduces the axial movement distance of the tea leaves within the drum, shortens the material residence time, and concentrates the screening power (such as the tumbling effect generated by the drum rotation) on the current screening section, thereby improving the processing efficiency per unit area of ​​the screen. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0020] Figure 1 A schematic diagram of a tea sieving device;

[0021] Figure 2 This is a cross-sectional view of the screening drum;

[0022] Figure 3 This is a sectional view of the movable partition;

[0023] Figure 4 for Figure 3 Enlarged view of point A in the middle.

[0024] The attached diagram shows the markings and corresponding component names:

[0025] 1-Frame, 2-Screening drum, 3-Grading screen section, 4-Screen hole, 5-Impurity separation section, 6-Impurity removal hole, 7-Feed hopper, 8-Main feed inlet, 9-Screening feed inlet, 10-First motor, 11-Drive shaft, 12-Guide shaft, 13-Second motor, 14-Drive gear, 15-Gear ring, 16-Mounting frame, 17-Roller, 18-Main screen section, 19-Pre-screen section, 20-Modible partition, 21-Cleaning component, 22-Assembly channel, 23-Elastic component, 24-Cleaning scraper, 25-Arc surface. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this utility model are only used to explain this utility model and are not intended to limit this utility model.

[0027] Example

[0028] Please refer to Figure 1 and Figure 2 This utility model provides a tea sieving device. It includes a frame 1, a sieving drum 2, multiple grading sieve sections 3, movable partitions 20, and a drive assembly. The frame 1 is an integral support structure, constructed from welded or bolted steel sections, with a corrosion-resistant surface treatment. The sieving drum 2 is mounted on the frame 1 and can rotate axially to convey the tea leaves inside. The sieving drum 2 is mounted via a rolling support assembly and driven by a transmission drive assembly. The inner wall of the sieving drum 2 can have spiral guide ribs distributed circumferentially, which push the tea leaves axially as the sieving drum 2 rotates; alternatively, the sieving drum 2 can be arranged at an angle, utilizing gravity to assist in the axial conveying of the tea leaves.

[0029] Multiple grading screen sections 3 are arranged sequentially along the axial direction of the screening drum 2, and along the tea conveying direction (from the feed end to the discharge end). The aperture 4 of the screen sections 3 from the first level to the Nth level (N≥2) increases progressively, i.e., d1<d2<…<d n (e.g., d1 = 1mm, d2 = 3mm, d3 = 5mm), the aperture difference Δd between adjacent grading screen sections 3 and 4 is 1-3mm. A movable partition 20 is installed inside the screening drum 2, its outer contour matching the inner contour of the screening drum 2, forming a circular plate shape. The movable partition 20 forms a clearance fit with the inner wall of the drum (clearance δ = 0.5-1.0mm). The movable partition 20 can divide the interior of the screening drum 2 into a main screening section 18 and a pre-screening section 19. The drive assembly is installed on the frame 1 and can drive the movable partition 20 to move axially along the screening drum 2. By controlling the position of the movable partition 20, the preset grading screen section 3 enters the main screening section 18, while the remaining grading screen sections 3 are in the pre-screening section 19.

[0030] During operation, the operator adds tea leaves through the feed end of the screening drum 2. The drive assembly first controls the movable partition 20 to move to its initial position, dividing the first-stage grading screen 3 near the feed end into the main screening zone 18, and the remaining grading screen 3 into the pre-screening zone 19. As the screening drum 2 rotates, the tea leaves tumble inside, continuously contacting the sieve holes 4 of the first-stage grading screen 3 in the main screening zone 18. Smaller tea leaves fall through the sieve holes 4 and are collected. After the tea leaves of this grade are screened, the drive assembly controls the movable partition 20 to move axially, bringing the first and second-stage grading screen 3 into the main screening zone 18, with the remainder in the pre-screening zone 19. The tea leaves then enter the second-stage grading screen 3 for screening. Because the sieve hole 4 of the second-stage grading screen 3 has a larger diameter than that of the first-stage grading screen 3, tea leaves that meet this grade fall through the sieve holes 4 and are collected. Following this logic, the main sieve section 18 is progressively expanded to the third and Nth grading sieve section 3 until all grades of tea leaves are sieved within the sieve drum 2, achieving a stepped grading system from smallest to largest particle size. This device dynamically adjusts the sieve area via movable partitions 20, and combined with the rotation of the sieve drum 2 and the gradient design of the sieve holes 4, it can efficiently and accurately sieve tea leaves at multiple grades, avoiding mixing of tea leaves of different particle sizes and improving sieve efficiency and grading accuracy.

[0031] Please refer to Figures 1 to 3 In some embodiments of this application, the drive assembly includes a first motor 10, a drive shaft 11, and a guide shaft 12. The first motor 10 is fixed to one side of the frame 1 by a motor mount, and its output shaft is coaxially connected to the drive shaft 11 by a coupling. The drive shaft 11 extends axially along the screening drum 2 and passes through the movable partition 20, and the two are connected by a threaded pair to form a transmission fit. The guide shaft 12 is arranged parallel to the drive shaft 11, and its two ends are fixed to the frame 1 by bearing seats. The outer diameter of the guide shaft 12 is clearance-fitted with the guide hole on the movable partition 20 to constrain the movable partition 20 to translate only axially. When the first motor 10 drives the drive shaft 11 to rotate in both directions, the movable partition 20 reciprocates linearly along the guide shaft 12 under the axial component force of the threaded pair. The stroke range covers the axial position of each grading screen section 3 in the screening drum 2, ensuring that the dynamic adjustment of the main screening section 18 meets the grading requirements of different teas.

[0032] It is important to note that, to ensure the rotational stability of the drive shaft 11 and to prevent radial runout caused by the other end of the drive shaft 11 being suspended in the air, the other end of the drive shaft 11 is mounted in the bearing housing of the frame 1 via a deep groove ball bearing (such as type 6208). This design effectively reduces the vibration and noise of the drive shaft 11 during operation, improves the overall rigidity and service life of the drive assembly, and ensures that the translational accuracy of the movable partition 20 is not affected by the deflection deformation of the drive shaft 11.

[0033] The drive shaft 11 is made of high-strength alloy material (such as 40Cr quenched and tempered), which has excellent torsional strength and wear resistance, and can effectively resist alternating loads during long-term transmission, avoiding breakage or deformation. The drive shaft 11 is arranged above the screening drum 2.

[0034] Please refer to Figure 4 In some embodiments of this application, the movable partition 20 has multiple assembly slots 22 evenly distributed along its circumferential direction, and each assembly slot 22 is equipped with a cleaning component 21. When the movable partition 20 moves axially, the cleaning component 21 moves synchronously with the movable partition 20. The cleaning component 21 can remove tea leaves, tea powder, and other residues adhering to the area around the sieve holes 4 and the wall of the screening drum 2, preventing the sieve holes 4 from becoming clogged and affecting the screening efficiency. This design combines the cleaning function with the movement of the partition to achieve synchronous cleaning during the screening process, reduce the frequency of manual intervention, and improve the automation level and hygiene performance of the equipment.

[0035] Specifically, the cleaning component 21 includes an elastic element 23 and a cleaning scraper 24. One end of the elastic element 23 (preferably a compression spring or elastic rubber column) is fixed to the bottom wall of the mounting channel 22, and the other end is connected to the cleaning scraper 24, forming an elastic support structure. The cleaning scraper 24 is an arc-shaped strip. One end of the cleaning scraper 24 is embedded in the mounting channel 22 and forms a sliding guide engagement with the side walls of the mounting channel 22. The other end of the cleaning scraper 24 extends to the inner wall of the screening drum 2. When the movable partition 20 moves axially, the cleaning scraper 24 moves synchronously with the movable partition 20. Under the action of the elastic element 23, the working surface of the cleaning scraper 24 adheres tightly to the inner wall of the screening drum 2, removing tea residue adhering to the sieve holes 4 and the wall surface through scraping motion. This structure utilizes the adaptive adjustment characteristics of the elastic element 23, allowing the cleaning scraper 24 to adapt to the minute deformations of the inner wall of the screening drum 2, ensuring uniform cleaning effects at different locations, while avoiding equipment wear or tea damage caused by rigid contact.

[0036] The cleaning scraper 24, facing the inner wall of the screening drum 2, is designed with an arc-shaped curved surface 25. The radius of curvature of this curved surface 25 precisely matches the radius of curvature of the inner wall of the screening drum 2 (error ≤ ±0.1mm), allowing the cleaning scraper 24 to closely conform to the contour of the inner wall of the screening drum 2. When the cleaning scraper 24 moves with the movable partition 20, the arc-shaped curved surface 25 slides along the wall of the screening drum 2 in a line contact manner, effectively covering the uneven areas of the inner wall and the dead corners around the screen holes 4, thus removing the adhering tea residue more thoroughly than a flat structure. At the same time, the transition design of the arc-shaped curved surface 25 reduces the movement resistance during the cleaning process and reduces the frictional wear between the cleaning scraper 24 and the inner wall of the screening drum 2.

[0037] Please refer to Figure 1In some embodiments of this application, the feed hopper 7 has a variable cross-section tubular structure. The upper end of the feed hopper 7 is a flared funnel-shaped main feed inlet 8, and the lower end of the feed hopper 7 is a screening inlet 9. The axis of the inlet is aligned with the axial direction of the feeding area of ​​the screening drum 2 and extends into the drum interior by 50mm to 100mm. When tea leaves are fed in through the main feed inlet 8, they slide down the inner wall of the feed hopper 7 under gravity and fall directly into the initial screening area of ​​the screening drum 2 through the screening inlet 9, without the need for additional power assistance. This design, by optimizing the feeding path and sealing structure, enables convenient feeding by operators while effectively avoiding interference from the rotation of the screening drum 2 on the feeding process, thus improving the ease of use of the equipment and the cleanliness of the working environment.

[0038] Please refer to Figure 1 and Figure 2 In some embodiments of this application, an impurity separation section 5 is provided at one end of the screening drum 2 near the feed hopper 7, and multiple impurity removal holes 6 are evenly distributed on the impurity separation section 5. When tea leaves enter the screening drum 2 from the feed hopper 7, the drive assembly controls the movable partition 20 to move forward to the end of the impurity separation section 5. The outer contour of the movable partition 20 fits tightly against the inner wall of the screening drum 2, forming a physical barrier to prevent the tea leaves from entering the downstream grading screen section 3. At this time, the screening drum 2 starts to rotate, and the tea leaves tumble in the impurity separation section 5 under the action of centrifugal force and gravity. Fine impurities and light foreign objects fall into the collection tank below through the impurity removal holes 6, while the tea leaves are intercepted because their size is larger than the aperture of the impurity removal holes 6. After the impurity removal is completed, the drive assembly drives the movable partition 20 to move backward again, releasing the obstruction to the grading screen section 3, so that the tea leaves can enter the subsequent grading screen section 3 and complete the particle size grading by passing through the grading screen section 3 with progressively larger apertures. This design achieves a sequential screening process of "removing impurities first and then grading" through the linkage between the movable partition 20 and the impurity separation section 5, effectively preventing impurities from clogging the grading sieve holes 4 and improving screening efficiency and tea quality.

[0039] Please refer to Figure 1 In some embodiments of this application, multiple rolling support assemblies are also arranged at intervals along the axial direction of the screening drum 2. Each set of support assemblies includes a mounting frame 16 and rollers 17 symmetrically arranged on both radial sides of the screening drum 2. The rollers 17 form a rotating pair with the mounting frame 16 through bearings. The outer periphery of the rollers 17 is covered with a polyurethane elastic layer, and the rollers 17 form a rolling fit with the annular guide rail on the outer wall of the screening drum 2. When the screening drum 2 rotates, the rollers 17 perform pure rolling motion along the guide rail. This structure reduces the deflection deformation of the drum through multi-point support, and at the same time reduces vibration transmission by utilizing the buffering effect of the elastic rollers 17, thereby improving the operational stability and service life of the equipment.

[0040] Please refer to Figure 1In some embodiments of this application, the transmission assembly includes a second motor 13, a transmission gear 14, and a gear ring 15. The second motor 13 is mounted on the frame 1, and its output end is connected to the transmission gear 14. The gear ring 15 is fitted onto the outside of the screening drum 2, and meshes with the transmission gear 14. The transmission gear 14 and the gear ring 15 form a gear pair transmission. When the second motor 13 drives the transmission gear 14 to rotate, the gear ring 15 drives the screening drum 2 to rotate synchronously, thus realizing the power input to the screening drum 2.

[0041] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A tea sieving device, characterized in that, include: Rack (1); Screening drum (2), which is mounted on the frame (1), is axially rotatable to convey the tea leaves inside; Multiple grading screen segments (3) are arranged sequentially along the axial direction on the screening drum (2). Each grading screen segment (3) includes multiple screen holes (4) arranged on the screening drum (2). The aperture of the screen holes (4) of the multiple grading screen segments (3) increases sequentially from the front stage to the rear stage. Movable partition (20) is installed inside the screening drum (2). The outer contour of the movable partition (20) is adapted to the inner contour of the screening drum (2). The movable partition (20) can divide the screening drum (2) into a main screening section (18) and a pre-screening section (19). A drive assembly is mounted on the frame (1) and is capable of driving the movable partition (20) to move axially along the screening drum (2), thereby controlling the preset grading screen segment (3) to enter the main screen partition (18).

2. The tea sieving device according to claim 1, characterized in that, The drive assembly includes a first motor (10), a drive shaft (11), and a guide shaft (12); The first motor (10) is mounted on the frame (1), and the output end of the first motor (10) is connected to the drive shaft (11); The drive shaft (11) is coaxially arranged with the movable partition (20), the drive shaft (11) passes through the movable partition (20), and the drive shaft (11) and the movable partition (20) are connected by threads; One end of the guide shaft (12) is connected to the frame (1), and the other end of the guide shaft (12) passes through the movable partition (20).

3. The tea sieving device according to claim 2, characterized in that, The movable partition (20) has multiple assembly channels (22) along the circumferential direction on its outer periphery, and a cleaning component (21) is installed in the assembly channels (22).

4. The tea sieving device according to claim 3, characterized in that, The cleaning assembly (21) includes an elastic element (23) and a cleaning scraper (24); One end of the elastic element (23) is connected to the bottom wall of the assembly channel (22), and the other end of the elastic element (23) is connected to the cleaning scraper (24); One end of the cleaning scraper (24) is guided and engaged with the assembly channel (22), and the other end of the cleaning scraper (24) can abut against the inner wall of the screening drum (2).

5. The tea sieving device according to claim 4, characterized in that, The cleaning scraper (24) has an arc surface (25) facing the inner wall of the screening drum (2), and the arc surface (25) can fit against the inner wall of the screening drum (2).

6. The tea sieving device according to any one of claims 1 to 5, characterized in that, It also includes a feed hopper (7), which is installed on the frame (1). One end of the feed hopper (7) is a funnel-shaped main feed inlet (8), and the other end of the feed hopper (7) is a screening inlet (9). The screening inlet (9) extends into the screening drum (2).

7. The tea sieving device according to claim 6, characterized in that, The screening drum (2) is provided with an impurity separation section (5) on the side near the feed hopper (7), and the impurity separation section (5) includes a plurality of impurity removal holes (6) provided on the screening drum (2).

8. The tea sieving device according to any one of claims 1 to 5, characterized in that, It also includes rolling support assemblies, a plurality of which are mounted on the frame (1); The rolling support assembly includes a mounting frame (16) and a roller (17) arranged on both sides of the screening drum (2). The bottom of the mounting frame (16) is mounted on the frame (1), and the roller (17) is rotatably mounted on the top of the mounting frame (16). The roller (17) rolls against the screening drum (2).

9. The tea sieving device according to any one of claims 1 to 5, characterized in that, It also includes a transmission assembly, which includes a second motor (13), a transmission gear (14), and a gear ring (15); The second motor (13) is mounted on the frame (1), and the output end of the second motor (13) is connected to the transmission gear (14); The gear ring (15) is fitted on the outside of the screening drum (2), and the gear ring (15) meshes with the transmission gear (14).

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