A rapeseed screening device
By combining wind power with screen sieving, and utilizing multiple convex ridges for turning and hood collection, the problem of poor separation between rapeseed and rapeseed pods was solved, achieving efficient sieving and improved oil yield, thus enhancing the market competitiveness of rapeseed.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- MIANYANG HUIDA GRAIN & OIL CO LTD
- Filing Date
- 2026-04-24
- Publication Date
- 2026-05-29
AI Technical Summary
Existing technologies are difficult to effectively separate rapeseed and rapeseed pods, especially in wind-powered and screen-screening equipment, where rapeseed pods are difficult to blow away or clog the screen holes, resulting in poor separation and affecting rapeseed quality and oil yield.
The system employs a combination of wind-driven blowing and screen sieving. Multiple raised ridges inside the screening cylinder cause the pods to tumble, while gaps and discharge ports are provided outside the cylinder. This allows for multiple blowing and interception of the rapeseed pods, and the screened rapeseed is then collected by the cylinder.
It improves the removal efficiency of rapeseed pods, prevents clogging, ensures screening efficiency, enhances rapeseed quality and oil yield, and reduces the problem of dark rapeseed oil color.
Smart Images
Figure CN224293964U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of material screening equipment technology, specifically to a rapeseed screening device. Background Technology
[0002] Rapeseed is an important oilseed crop in China. During the rapeseed harvesting process, whether it is traditional manual harvesting or modern mechanized harvesting, it is difficult to avoid the mixing of rapeseed pods. When rapeseed is sold as a commodity, excessive impurities will lower its grade and thus directly lead to a lower price. When pressing rapeseed for oil, since rapeseed pods contain almost no oil and absorb oil, the oil yield will decrease. In addition, during the roasting process before pressing, rapeseed pods are prone to developing a burnt taste, which will affect the flavor of the finished rapeseed oil. Furthermore, rapeseed oil pressed from rapeseed containing pods is usually darker in color and of poorer quality.
[0003] In existing technologies, separation is typically achieved by using a sieve and taking advantage of the shape difference between rapeseed and rapeseed pods; or by using wind power to separate rapeseed and rapeseed pods, taking advantage of the fact that rapeseed pods are lighter and larger than rapeseed. For example, Chinese Patent CN202220633186.4 discloses a rapeseed impurity screening device for rapeseed production and processing, which uses an exhaust fan above to adsorb light impurities contained in rapeseed, and uses a sieve shell below to screen the rapeseed, and uses a rotating agitator to move the rapeseed to better screen it.
[0004] However, due to the hulling and drying processes during rapeseed harvesting, rapeseed pods mixed in with the seeds often break into various shapes and sizes. Therefore, when using wind power to remove the pods, some pods inevitably become difficult to separate due to both their size (wind-exposed area) and weight. Increasing the wind force, however, makes it difficult to ensure that the rapeseed seeds are not blown away. Existing wind-powered screening equipment struggles to achieve satisfactory separation. Screen-based screening equipment also inevitably suffers from short rapeseed pods that vertically insert into the mesh, passing directly through the screen and causing poor screening results, or clogging the mesh and reducing screening efficiency. Utility Model Content
[0005] The purpose of this invention is to provide a rapeseed screening device that can at least partially overcome the above-mentioned technical problems. It can effectively remove rapeseed pods from rapeseed based on the combined action of wind blowing and screen screening. Furthermore, it can blow the material entering the rapeseed screening device multiple times, thereby improving the removal effect of rapeseed pods.
[0006] This utility model provides a rapeseed screening device comprising a frame, a screening cylinder, a blower, and a drive motor. The screening cylinder is tubular and rotatably mounted on the frame with its axis horizontal. A plurality of screening holes are formed on the circumferential wall of the screening cylinder. A feed hopper is also fixedly mounted on the frame, located at the feed end of the screening cylinder. The feed hopper is used to guide the material to be screened into the screening cylinder via the upper part of the feed end. The blower is fixedly connected to the frame and located at the feed end of the screening cylinder, with the blower's outlet direction from the feed end to the discharge end of the screening cylinder. The drive motor is used to drive the screening cylinder to rotate around its axis. Multiple protruding ribs extending along the length of the screening cylinder are provided on the inner side of the screening cylinder, and each protruding rib is evenly distributed along the circumference of the screening cylinder.
[0007] Furthermore, a tapered tube is provided at both ends of the screening cylinder, and the larger end of the tapered tube is fixedly connected to the end face of the screening cylinder.
[0008] Furthermore, the rapeseed screening device also includes a cover cylinder; the cover cylinder is sleeved outside the screening cylinder and fixedly connected to the frame, there is a radial gap between the inner wall of the cover cylinder and the outer wall of the screening cylinder, and a discharge port is provided at the bottom of the cover cylinder.
[0009] Furthermore, the inner wall of the cover is cylindrical, and the axis of the inner wall of the cover is located below the axis of the screening cylinder.
[0010] Furthermore, the cover cylinder includes an upper section and a lower section; the inner wall of the lower section has an arc-shaped cross-section, and the axis of the inner wall of the lower section coincides with the axis of the screening cylinder; for any point on the inner wall of the upper section, the distance between that point and the axis of the screening cylinder gradually decreases from bottom to top.
[0011] Furthermore, at the bottom position of the cover cylinder, the gap satisfies 1.5D < L < 2.5D, where D represents the diameter of the sieve hole and L represents the gap at the bottom position of the cover cylinder.
[0012] Furthermore, the screening cylinder includes a screen section and a leak-proof section along its length, the screen holes are opened on the screen section, and the discharge port is opened below the leak-proof section.
[0013] Furthermore, the discharge port is located at the middle of the length of the cover cylinder, and the inner diameter of the cover cylinder gradually decreases from the discharge port to both ends of the cover cylinder; and the outer diameter of the screening cylinder gradually decreases from the leak-proof section to both ends of the screening cylinder.
[0014] Furthermore, the diameter of the sieve holes is 1.5 mm to 2.5 mm.
[0015] Furthermore, the diameter of the sieve holes gradually increases from the inside to the outside of the sieve cylinder, and the diameter of the sieve holes is 1.5 mm to 2.5 mm inside the sieve cylinder.
[0016] Compared with the prior art, this utility model has the following advantages and beneficial effects:
[0017] 1. The rapeseed screening device provided in this embodiment continuously injects rapeseed into the feed hopper, allowing the rapeseed to enter the screening cylinder through the upper part of the feed end. During the process of the rapeseed falling from the feed hopper into the screening cylinder, the blowing action of the blower causes the lighter and / or larger surface area of the rapeseed pods to be blown out from the discharge end of the screening cylinder. Simultaneously, under the rotation of the screening cylinder, the rapeseed inside passes through the screen holes to the outside of the screening cylinder, while the rapeseed pods are intercepted inside the screening cylinder. It is worth noting that multiple raised ribs extending along the length of the screening cylinder are provided inside the screening cylinder. These raised ribs serve as reinforcing ribs to strengthen the screening process. The structure of the screen cylinder is strong enough to prevent deformation and damage when rapeseed accumulates. More importantly, it can "turn over" the rapeseed and pods trapped inside the screen cylinder during its rotation. That is, the rapeseed and pods trapped between any two adjacent convex ridges will be lifted up with the rotation of the screen cylinder. After rising to a certain height, the side walls of the convex ridges can no longer restrain these trapped rapeseed and pods, and they will fall down again. Then they will be blown by the fan again. In other words, these convex ridges can make the material to be screened inside the screen cylinder receive multiple blown action from the fan, thereby enhancing the removal effect of rapeseed pods.
[0018] 2. The rapeseed screening device provided in this embodiment of the present disclosure can effectively collect rapeseed passing through the screen holes by setting a cover, and then discharge it from the discharge port after it is collected, which facilitates the collection of rapeseed after screening.
[0019] 3. The rapeseed screening device provided in this embodiment has a large gap between the lower part of the cover and the screening cylinder, allowing rapeseed to pass smoothly through the screen holes. This gap prevents rapeseed pods inserted into the screen holes from falling into the gap. As the screening cylinder rotates, the rapeseed pods inserted into the screen holes gradually move upward. During the upward movement, the gap at the location of the rapeseed pod gradually decreases, and the rapeseed pod is continuously pushed out of the screen holes. After falling out of the screen holes, it will be blown away again by the blower. That is to say, the cover can prevent rapeseed pods from passing through the screen holes and contaminating the screened rapeseed, and can also push the rapeseed pods inserted into the screen holes, thereby preventing the rapeseed pods from clogging the screen holes. Attached Figure Description
[0020] 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:
[0021] Figure 1 This is a three-dimensional structural schematic diagram of the rapeseed screening device according to an embodiment of the present invention;
[0022] Figure 2 This is another three-dimensional structural schematic diagram of the rapeseed screening device according to an embodiment of the present utility model;
[0023] Figure 3 This is a cross-sectional view of the rapeseed screening device according to an embodiment of the present invention;
[0024] Figure 4 This is another cross-sectional view of the rapeseed screening device according to an embodiment of the present invention.
[0025] The attached diagram shows the markings and corresponding component names:
[0026] 1-Frame; 2-Screening cylinder; 21-Screen hole; 22-Feed end; 23-Discharge end; 24-Protruding ridge; 25-Conical tube section; 26-Screen section; 27-Leak-proof section; 3-Fan; 4-Feed hopper; 5-Cover cylinder; 51-Discharge port; 52-Upper section; 53-Lower section; 61-Motor; 62-Drive motor. Detailed Implementation
[0027] 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.
[0028] Rapeseed is an important oilseed crop in China. During the rapeseed harvesting process, whether it is traditional manual harvesting or modern mechanized harvesting, it is difficult to avoid the mixing of rapeseed pods. When rapeseed is sold as a commodity, excessive impurities will lower its grade and thus directly lead to a lower price. When pressing rapeseed for oil, since rapeseed pods contain almost no oil and absorb oil, the oil yield will decrease. In addition, during the roasting process before pressing, rapeseed pods are prone to developing a burnt taste, which will affect the flavor of the finished rapeseed oil. Furthermore, rapeseed oil pressed from rapeseed containing pods is usually darker in color and of poorer quality.
[0029] In existing technologies, separation is typically achieved by using a sieve and taking advantage of the shape difference between rapeseed and rapeseed pods; or by using wind power to separate rapeseed and rapeseed pods, taking advantage of the fact that rapeseed pods are lighter and larger than rapeseed. For example, Chinese Patent CN202220633186.4 discloses a rapeseed impurity screening device for rapeseed production and processing, which uses an exhaust fan above to adsorb light impurities contained in rapeseed, and uses a sieve shell below to screen the rapeseed, and uses a rotating agitator to move the rapeseed to better screen it.
[0030] However, due to the hulling and drying processes during rapeseed harvesting, rapeseed pods mixed in with the seeds often break into various shapes and sizes. Therefore, when using wind power to remove the pods, some pods inevitably become difficult to separate due to both their size (wind-exposed area) and weight. Increasing the wind force, however, makes it difficult to ensure that the rapeseed seeds are not blown away. Existing wind-powered screening equipment struggles to achieve satisfactory separation. Screen-based screening equipment also inevitably suffers from short rapeseed pods that vertically insert into the mesh, passing directly through the screen and causing poor screening results, or clogging the mesh and reducing screening efficiency.
[0031] Therefore, this utility model proposes a rapeseed screening device that can effectively remove rapeseed pods from rapeseed based on the combined action of wind blowing and screen screening. Furthermore, it can blow the material entering the rapeseed screening device multiple times, thereby improving the removal effect of rapeseed pods.
[0032] Example 1 Figures 1 to 4 As shown, this embodiment provides a rapeseed screening device, which includes a frame 1, a screening cylinder 2, a blower 3 and a drive motor 62;
[0033] The screening cylinder 2 is tubular, and the screening cylinder 2 is rotatably mounted on the frame 1 with the axis of the screening cylinder 2 being horizontal. A plurality of screen holes 21 are provided on the peripheral wall of the screening cylinder 2.
[0034] A feeding hopper 4 is also fixedly installed on the frame 1. The feeding hopper 4 is located at the feeding end 22 of the screening cylinder 2. The feeding hopper 4 is used to guide the material to be screened into the screening cylinder 2 through the upper part of the feeding end 22.
[0035] The blower 3 is fixedly connected to the frame 1 and is located at the feed end 22 of the screening cylinder 2. The air outlet direction of the blower 3 is from the feed end 22 of the screening cylinder 2 to the discharge end 23.
[0036] The drive motor 62 is used to drive the screening cylinder 2 to rotate around the axis;
[0037] Multiple protruding ribs 24 extending along the length of the screening cylinder 2 are provided on the inner side of the screening cylinder 2, and each of the protruding ribs 24 is evenly distributed along the circumference of the screening cylinder 2.
[0038] Specifically, the diameter of the sieve aperture 21 is 1.5 mm to 2.5 mm. Therefore, the sieve aperture 21 allows rapeseed to pass through smoothly while effectively intercepting the seed pods.
[0039] It should be understood that the fan 3 is driven, for example, by a motor 61. The output shaft of the motor 61 and the rotating shaft of the fan 3 can be directly and coaxially fixedly connected, or the rotating shaft of the fan 3 can be driven to rotate via chain drive, synchronous belt drive, gear drive, etc. (e.g.) Figure 2 As shown in the figure, the motor 61 drives the shaft of the fan 3 to rotate via a synchronous belt. Similarly, the drive motor 62 can also drive the screening cylinder 2 to rotate around its own axis via chain drive, synchronous belt drive, gear drive, etc. (e.g., Figure 1 As shown in the figure, the drive motor 62 drives the screening cylinder 2 to rotate around its own axis via a synchronous belt (which will not be described in detail here).
[0040] Accordingly, the rapeseed screening device provided in this embodiment continuously injects rapeseed into the feed hopper 4, allowing the rapeseed to enter the screening cylinder 2 through the upper part of the feed end 22. During the process of the rapeseed falling from the feed hopper 4 into the screening cylinder 2, the blowing action of the blower 3 can cause the light and / or large rapeseed pods contained in the rapeseed to be blown out from the discharge end 23 of the screening cylinder 2. At the same time, under the rotation of the screening cylinder 2, the rapeseed in the screening cylinder 2 passes through the screen holes 21 to the outside of the screening cylinder 2, while the rapeseed pods are intercepted on the inside of the screening cylinder 2. It is worth noting that multiple protruding ribs 24 extending along the length of the screening cylinder 2 are provided on the inner side of the screening cylinder 2. These protruding ribs 24 serve two purposes: firstly, they act as reinforcing ribs to strengthen the structural strength of the screening cylinder 2, preventing deformation and damage when rapeseed accumulates; more importantly, they can "turn over" the rapeseed and rapeseed pods trapped inside the screening cylinder 2 during its rotation. That is, the rapeseed and rapeseed pods trapped between any two adjacent protruding ribs 24 will be lifted up with the rotation of the screening cylinder 2, and then, after rising to a certain height, The sidewalls of the protruding ridges 24 can no longer restrain these retained rapeseed and rapeseed pods, and they will fall again. They will then be blown by the fan 3 again. That is to say, these protruding ridges 24 can make the material to be screened inside the screening cylinder 2 be blown by the fan 3 multiple times, thereby enhancing the removal effect of rapeseed pods (for broken rapeseed pods with small wind-receiving area and slightly large mass, a single blowing action is not enough to move them along the length of the screening cylinder 2 to the discharge end 23. Multiple blowing actions can effectively remove these broken rapeseed pods).
[0041] Preferably, a tapered tube portion 25 is provided at both ends of the screening cylinder 2, and the larger end of the tapered tube portion 25 is fixedly connected to the end face of the screening cylinder 2.
[0042] Based on this, by setting the conical tube section 25, it is possible to effectively prevent the rapeseed "turned over" by the protruding ridge 24 from splashing out from both ends of the screening cylinder 2.
[0043] Example 2 Figures 1 to 4 As shown, this embodiment is based on embodiment 1, except that in this embodiment, the rapeseed screening device further includes a cover cylinder 5;
[0044] The cover 5 is sleeved outside the screening cylinder 2 and fixedly connected to the frame 1. There is a radial gap between the inner wall of the cover 5 and the outer wall of the screening cylinder 2. A discharge port 51 is provided at the bottom of the cover 5.
[0045] Accordingly, the rapeseed screening device provided in this embodiment can effectively collect rapeseed passing through the screen holes 21 by setting the cover 5, and then discharge it from the discharge port 51 after it is collected, which makes it easier to collect the rapeseed after screening.
[0046] Specifically, the inner wall of the cover cylinder 5 is cylindrical, and the axis of the inner wall of the cover cylinder 5 is located below the axis of the screening cylinder 2.
[0047] At the bottom of the cover 5, the gap satisfies 1.5D < L < 2.5D, where D represents the diameter of the sieve hole 21 and L represents the gap at the bottom of the cover 5.
[0048] Therefore, the gap between the lower part of the cover 5 and the screening cylinder 2 is relatively large, allowing the rapeseed to pass smoothly through the sieve holes 21. This gap also prevents rapeseed pods inserted into the sieve holes 21 from falling into it (even broken pods, being long and thin, will have one end remaining inside the screening cylinder 2 even if inserted through the sieve hole 21 due to the resistance of the cover 5). As the screening cylinder 2 rotates, the rapeseed pods inserted into the sieve holes 21 gradually move upwards. During this upward movement, the gap at the location of the pod gradually decreases, causing the pods to be continuously pushed out of the sieve holes 21. After falling out of the sieve holes 21, they will be blown away again by the blower 3. In other words, the cover 5, on the one hand, prevents rapeseed pods from passing through the sieve holes 21 and contaminating the screened rapeseed; on the other hand, it pushes the rapeseed pods inserted into the sieve holes 21, thus preventing them from clogging the sieve holes 21.
[0049] Preferably, the diameter of the sieve holes 21 gradually increases from the inner side to the outer side of the sieve cylinder 2, and the diameter of the sieve holes 21 is 1.5 mm to 2.5 mm inside the sieve cylinder 2. Therefore, the sieve holes 21 allow rapeseed to pass through smoothly while effectively intercepting the pods. Furthermore, after being inserted into the sieve holes 21, the pods are more easily pushed back into the inner side of the sieve cylinder 2 by the push of the cover cylinder 5.
[0050] Example 3 Figures 1 to 4 As shown, this embodiment is based on embodiment 2, the difference being that in this embodiment, the cover 5 includes an upper section 52 and a lower section 53; the inner wall cross-section of the lower section 53 is arc-shaped, and the axis of the inner wall of the lower section 53 coincides with the axis of the screening cylinder 2; for any point on the inner wall of the upper section 52, the distance between that point and the axis of the screening cylinder 2 gradually decreases from bottom to top.
[0051] Compared to the cylindrical cover 5 in Embodiment 2, in this embodiment, the gap between the lower section 53 of the cover 5 and the sieve cylinder 2 remains unchanged, thereby reducing the impact of the gradually decreasing gap from bottom to top on the smoothness of rapeseed passing through the sieve holes 21.
[0052] Example 4 Figures 1 to 4 As shown, this embodiment is based on embodiment 2, the difference being that in this embodiment:
[0053] The screening cylinder 2 includes a screen section 26 and a leak-proof section 27 along its length. The screen holes 21 are opened on the screen section 26, and the discharge port 51 is opened below the leak-proof section 27.
[0054] Therefore, the rapeseed screening device provided in this embodiment, by setting screen sections 26 and leak-proof sections 27 along the length of the screening cylinder 2, and opening screen holes 21 only in the screening sections, while not setting screen holes 21 in the leak-proof section 27 above the discharge port 51, can effectively prevent rapeseed pods from directly passing through the screening cylinder 2 and mixing into the screened rapeseed from the discharge port 51. This effectively ensures the interception effect of the cover cylinder 5 on the rapeseed pods.
[0055] Specifically, the discharge port 51 is located at the middle of the length of the cover cylinder 5, and the inner diameter of the cover cylinder 5 gradually decreases from the discharge port 51 to both ends of the cover cylinder 5; and the outer diameter of the screening cylinder 2 gradually decreases from the leak-proof section 27 to both ends of the screening cylinder 2.
[0056] Accordingly, the gap between the cover cylinder 5 and the screening cylinder 2 is uniform along the length of the screening cylinder 2 and has a certain slope, which can ensure that the rapeseed passing through the screen hole 21 rolls smoothly in the relatively narrow gap and is discharged through the discharge port 51.
[0057] It should be understood that, unless otherwise specified in this application, the term "rotational installation" means that the two parts can only rotate relative to each other and cannot move axially relative to each other. The means of restricting the axial relative movement of the two parts are, for example, providing a shoulder and an annular groove at the position where the two parts rotate together.
[0058] 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 rapeseed screening device, characterized in that, include: The frame (1), screening cylinder (2), fan (3) and drive motor (62); The screening cylinder (2) is tubular, and the screening cylinder (2) is rotatably mounted on the frame (1) with the axis of the screening cylinder (2) being horizontal. Several screen holes (21) are provided on the peripheral wall of the screening cylinder (2). A feeding hopper (4) is also fixedly installed on the frame (1). The feeding hopper (4) is located at the feeding end (22) of the screening cylinder (2). The feeding hopper (4) is used to guide the material to be screened into the screening cylinder (2) through the upper part of the feeding end (22). The blower (3) is fixedly connected to the frame (1) and located at the feed end (22) of the screening cylinder (2). The air outlet direction of the blower (3) is from the feed end (22) of the screening cylinder (2) to the discharge end (23). The drive motor (62) is used to drive the screening cylinder (2) to rotate around the axis; Multiple protruding ribs (24) extending along the length of the screening cylinder (2) are provided on the inner side of the screening cylinder (2), and each of the protruding ribs (24) is evenly distributed along the circumference of the screening cylinder (2).
2. The rapeseed screening device according to claim 1, characterized in that, A conical tube section (25) is provided at both ends of the screening cylinder (2), and the large end of the conical tube section (25) is fixedly connected to the end face of the screening cylinder (2).
3. The rapeseed screening device according to claim 2, characterized in that, The rapeseed screening device also includes a cover (5). The cover (5) is sleeved on the outside of the screening cylinder (2) and fixedly connected to the frame (1). There is a radial gap between the inner wall of the cover (5) and the outer wall of the screening cylinder (2). A discharge port (51) is provided at the bottom of the cover (5).
4. The rapeseed screening device according to claim 3, characterized in that, The inner wall of the cover (5) is cylindrical, and the axis of the inner wall of the cover (5) is located below the axis of the screening cylinder (2).
5. The rapeseed screening device according to claim 3, characterized in that, The cover (5) includes an upper section (52) and a lower section (53); the inner wall of the lower section (53) has an arc-shaped cross-section, and the axis of the inner wall of the lower section (53) coincides with the axis of the screening cylinder (2); for any point on the inner wall of the upper section (52), the distance between that point and the axis of the screening cylinder (2) gradually decreases from bottom to top.
6. The rapeseed screening device according to claim 4 or 5, characterized in that, At the bottom position of the cover (5), the gap satisfies 1.5D < L < 2.5D, where D represents the diameter of the sieve hole (21) and L represents the gap at the bottom position of the cover (5).
7. The rapeseed screening device according to claim 3, characterized in that, The screening cylinder (2) includes a screen section (26) and a leak-proof section (27) along its length. The screen holes (21) are opened on the screen section (26), and the discharge port (51) is opened below the leak-proof section (27).
8. The rapeseed screening device according to claim 7, characterized in that, The discharge port (51) is located at the middle of the length of the cover (5). From the discharge port (51) to both ends of the cover (5), the inner diameter of the cover (5) gradually decreases; and from the leak-proof section (27) to both ends of the screening cylinder (2), the outer diameter of the screening cylinder (2) gradually decreases.
9. The rapeseed screening device according to claim 1, characterized in that, The diameter of the sieve hole (21) is 1.5 mm to 2.5 mm.
10. The rapeseed screening device according to claim 1, characterized in that, From the inside to the outside of the sieve cylinder (2), the diameter of the sieve hole (21) gradually increases, and the diameter of the sieve hole (21) inside the sieve cylinder (2) is 1.5 mm to 2.5 mm.