Grain dryer
By designing the spiral feeding plate and venting structure, the problems of uneven heating and low heat utilization in crossflow grain drying devices are solved, achieving uniform heating of materials and efficient utilization of thermal energy, thus reducing energy consumption.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-19
- Publication Date
- 2026-04-03
AI Technical Summary
Crossflow grain drying equipment suffers from uneven heating and low heat utilization, resulting in moisture gradients in the grains during the drying process, which leads to increased mold or breakage rates and low energy utilization.
The spiral feeding plate design includes a left half ring and a right half ring. The left half ring is connected by a flexible metal plate and vibrates through a vibrator. The material slowly descends and tumbles on the spiral feeding plate, while the right half ring falls quickly. Combined with the design of the central cylinder and vent holes, the material can be frequently switched between the left and right half rings to ensure uniform heating.
This results in more uniform heating of materials, improves the heat utilization rate of hot air, reduces energy consumption, and avoids mold or breakage problems caused by uneven heating.
Smart Images
Figure CN121782843A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a grain dryer. Background Technology
[0002] Crossflow grain dryers are the most widely used type of machine in large grain silos in China. Their structural principle involves the vertical fall of grain and the horizontal flow of hot air in cross-contact. This design results in uneven heating of the grain during the drying process, creating a significant moisture gradient. Grain closer to the hot air inlet dries faster and loses more moisture due to direct contact with the high-temperature air; conversely, grain further away from the inlet dries slower and retains more moisture because the hot air travels a longer distance and its temperature decays more quickly. This lateral moisture difference can lead to localized mold growth or increased breakage during subsequent storage (such as rice cracking due to uneven moisture content). Furthermore, the hot air circulation method and airflow resistance of crossflow dryers result in lower energy efficiency, with unit heat consumption significantly higher than other types such as mixed-flow and co-flow dryers. The main reasons include: Hot air short circuit: The horizontal airflow in the crossflow tower is prone to "short circuit" (that is, hot air is discharged directly without fully penetrating the grain layer), resulting in waste of heat energy.
[0003] High airflow resistance: The sieve structure of the crossflow tower and the accumulation of grain layers increase airflow resistance, causing the fan to require more power to maintain the hot air flow, further increasing energy consumption. Summary of the Invention
[0004] The purpose of this invention is to provide a grain dryer to solve the technical problems of uneven heating and low heat utilization rate in existing crossflow grain drying devices.
[0005] The technical solution of the present invention is as follows: A grain dryer includes: The drying drum has a vertical axis, a feed inlet at the top and a discharge outlet at the bottom, and first ventilation holes are evenly distributed on its drum wall. The hot air generator is set in the left-right direction and blows hot air onto the drying cylinder from left to right. The central cylinder is located inside the drying cylinder and is coaxial with the drying cylinder. Its cylinder wall has evenly distributed second vent holes and its upper end has a cap. A spiral feeder plate is set in the annular space between the drying cylinder and the central cylinder. The spiral feeder plate is provided with a third vent hole. The spiral feeder plate includes multiple feeder plate units. The vertical projection of each feeder plate unit is a circle. Each feeder plate unit includes a left half ring and a right half ring connected by a flexible metal plate. The right half ring is fixedly connected to the drying cylinder and the central cylinder respectively. The left half ring is slidably engaged with the drying cylinder and the central cylinder respectively. A support part is provided on the inner wall of the left side of the drying cylinder. An elastic buffer column is set on the support part to abut against the lower surface of the left half ring. A vibrator is also installed on the lower surface of the left half ring. The spiral helix angle of the right half ring is greater than that of the left half ring. After the vibrator is started, it can drive the left half ring to vibrate, so that the material on it will slowly move downward.
[0006] The beneficial effects of this technical solution are as follows: When the grain dryer is in use, grains or cereals enter through the feed inlet of the drying cylinder and first fall onto the spiral feed plate in the annular space. Due to the weight of the material and the spiral downward trend of the upper surface of the spiral feed plate, the material will slowly descend along the upper surface of the spiral feed plate. When the material is on the left half of the left ring, the spiral angle of the left half ring is relatively small, so the descent is relatively slow. The hot air blows from left to right. After passing through the first vent of the drying cylinder, the hot air first contacts the material on the left half ring. Some of the hot air contacts the material after passing through the third vent on the left half ring. The material can contact the hot air from both the top and bottom. The material moves slowly up and down on the left half ring, so it can fully contact the hot air for drying. To facilitate the material's falling and tumbling on the left half ring, the upper and lower ends of the left half ring are connected to the fixed right half ring by flexible metal plates. So that the left half ring can sway relative to the right half ring, the left side of the left half ring overlaps with the elastic buffer column of the support, and a vibrator is provided on the left half ring. By activating the vibrator, the left half ring can be driven to vibrate, realizing the tumbling of the material and promoting the gradual falling of the material to avoid the material getting stuck. Then the material flows from the left half ring through the flexible metal plate to the right half ring. Because the spiral angle of the right half ring is relatively large, that is, the right half ring is relatively steep, the material can fall quickly so that it can quickly enter the next left half ring. This is because the right half ring corresponds to the downstream of the hot air, the temperature has been reduced to a certain extent and is blocked by the central cylinder and the left half ring to a certain extent, so the heat is slightly insufficient. In order to improve the drying efficiency, the material is made to flow as fast as possible on the right half ring. However, although the material flow on the right half ring is accelerated, the right half ring is also provided with a third vent, and the central cylinder is provided with a second vent, so the material can also be heated by the hot air on the right half ring. Furthermore, since the spiral feeder plate comprises multiple feeder plate units, the material frequently switches between the left and right halves of the ring. That is, after being heated by high-temperature hot air on the left half of the ring, the material enters the right half of the ring where it is heated by lower-temperature hot air, and then enters the next left half of the ring for high-temperature heating, repeating this cycle. This avoids the problem of uneven heating on one side of the material. Therefore, this application can achieve more uniform heating of the material, avoiding a series of problems caused by uneven heating, and allowing the hot air to contact the material for a longer time to fully utilize the energy of the hot air, thereby improving the heat utilization rate of the hot air and reducing energy consumption.
[0007] Based on the above solution, further improvements are made as follows: the upper surface of the spiral feed plate has multiple sequentially descending small steps to promote material tumbling. This facilitates the exchange of positions between the upper and lower layers of material and promotes more uniform heating of the material.
[0008] Based on the above scheme, further improvements are made as follows: Multiple guide ribs are evenly distributed on the upper surface of the spiral feed plate. These guide ribs extend downwards at an angle from near the central cylinder towards the drying cylinder, guiding the material towards the drying cylinder. Since the spiral surface of the spiral feed plate provides centripetal force to the material in the center direction, guide ribs are provided to prevent material accumulation near the central cylinder. This allows the material to periodically flow towards the drying cylinder and then back towards the central cylinder using centripetal force, creating an exchange of positions in the inner and outer directions, further improving the uniformity of heating.
[0009] Based on the above solution, the following improvement is made: the upper surface of the flexible metal plate is flush with the upper surface of the corresponding left and right half-ring joint. This prevents material from getting stuck when flowing through the flexible metal plate.
[0010] Based on the above scheme, the following improvements are made: an installation cylinder is coaxially sleeved outside the drying cylinder, and coaxial air inlets and outlets are respectively provided on the left and right sides of the installation cylinder. The air inlet is connected to the pipeline of the hot air generating device, and the air outlet is connected to the exhaust pipeline.
[0011] Based on the above solution, the following improvements are made: the cap is a conical structure, smaller at the top and larger at the bottom, which can guide the material.
[0012] Based on the above scheme, the following improvements are made: a flared structure is provided at the feed inlet. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the internal structure of a specific embodiment of the grain dryer of the present invention; Figure 2 for Figure 1 A magnified view of a section at point A in the middle; Figure 3 for Figure 1 Top view; In the diagram: 1-Drying cylinder, 11-Feed inlet, 12-First vent, 13-Support, 14-Elastic buffer column, 2-Central cylinder, 21-Second vent, 22-Cap, 3-Spiral feed plate, 31-Third vent, 32-Left half ring, 33-Right half ring, 34-Flexible metal plate, 35-Vibrator, 36-Small step, 37-Guide rib, 4-Mounting cylinder, 41-Air inlet, 42-Air outlet, 43-Pipe of hot air generator, 44-Exhaust pipe. Detailed Implementation
[0014] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described embodiments are merely some embodiments of the invention, and not all embodiments. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0015] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.
[0016] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0017] The features and performance of the present invention will be further described in detail below with reference to embodiments.
[0018] A specific embodiment of the grain dryer of the present invention: as follows Figure 1-3 As shown, the grain dryer includes a drying cylinder 1, a hot air generating device, a central cylinder 2, and a spiral feed plate 3.
[0019] The drying cylinder 1 is vertically oriented, with a feed inlet 11 at the upper end and a discharge outlet at the lower end. First air vents 12 are evenly distributed on the cylinder wall, with the diameter of the vents 12 being smaller than the particle size of the material. A funnel-shaped structure is provided at the feed inlet 11.
[0020] The hot air generator is set in the left-right direction and blows hot air onto the drying cylinder 1 in the direction from left to right.
[0021] The central cylinder 2 is located inside the drying cylinder 1 and is coaxial with it. Its cylinder wall has evenly distributed second ventilation holes 21, and its upper end has a cap 22. The cap 22 has a conical structure that is smaller at the top and larger at the bottom, which guides the material.
[0022] The spiral feed plate 3 is positioned within the annular space between the drying cylinder 1 and the central cylinder 2. The spiral feed plate 3 has a third vent 31. It comprises multiple feed plate units, each with a vertical projection that is a ring. Each feed plate unit includes a left half-ring 32 and a right half-ring 33 connected by a flexible metal plate 34. The right half-ring 33 is fixedly connected to both the drying cylinder 1 and the central cylinder 2, while the left half-ring 32 is slidably engaged with both. A support portion 13 is located on the inner left side of the drying cylinder 1. An elastic buffer column 14 is installed on the support portion 13, abutting against the lower surface of the left half-ring 32. A vibrator 35 is also installed on the lower surface of the left half-ring 32. The spiral helix angle of the right half-ring 33 is greater than that of the left half-ring 32. The upper surface of the spiral feed plate 3 has multiple sequentially descending small steps 36 to promote material tumbling. This facilitates the exchange of positions between the upper and lower layers of material, resulting in more uniform heating. The upper surface of the spiral feed plate 3 is evenly distributed with multiple guide ribs 37. The guide ribs 37 extend downward at an angle from near the central cylinder 2 towards near the drying cylinder 1 to guide the material toward the drying cylinder 1. Since the spiral surface of the spiral feed plate 3 can provide centripetal force to the material in the center direction, in order to prevent the material from accumulating in the area near the central cylinder 2, the guide ribs 37 are set to guide the material, so that the material flows periodically toward the drying cylinder 1, and then flows toward the central cylinder 2 using centripetal force, so as to form an exchange of positions in the inner and outer directions, further improving the uniformity of heating. After the vibrator 35 is started, it can drive the left half ring 32 to vibrate, so that the material on it slowly moves downward.
[0023] When the grain dryer is in use, grains or cereals enter through the feed inlet 11 of the drying cylinder 1 and first fall onto the spiral feed plate 3 in the annular space. Due to the weight of the material and the spiral downward trend of the upper surface of the spiral feed plate 3, the material will slowly descend along the upper surface of the spiral feed plate 3. When the material is on the left half ring 32, the descent is relatively slow because the spiral angle of the left half ring 32 is relatively small. The hot air blows from left to right. After passing through the first vent 12 of the drying cylinder 1, the hot air first contacts the material on the left half ring 32. Some of the hot air contacts the material after passing through the third vent 31 on the left half ring 32. The material can contact the hot air from both the top and bottom. The material moves slowly up and down on the left half ring 32, so it can fully contact the hot air for drying. In order to facilitate the material falling and tumbling on the left half ring 32, the upper and lower ends of the left half ring 32 are connected to the fixed right half ring 33 by flexible metal plates 34, so that the left half ring 32 can be relative to the right half ring 33. The left half-ring 32 oscillates, with its left and right sides overlapping the elastic buffer column 14 of the support part 13. A vibrator 35 is installed on the left half-ring 32. Activating the vibrator 35 causes the left half-ring 32 to vibrate, tumbling the material and promoting its gradual descent to prevent jamming. Subsequently, the material flows from the left half-ring 32 through the flexible metal plate 34 to the right half-ring 33. Due to the larger helix angle of the right half-ring 33 (i.e., its steeper slope), the material falls quickly to facilitate its rapid transition to the next ring. The material flows through the left half-ring 32 because the right half-ring 33 corresponds to the downstream of the hot air, where the temperature has already decreased and is somewhat blocked by the central cylinder 2 and the left half-ring 32, resulting in slightly insufficient heat. To improve drying efficiency, the material is made to flow as quickly as possible on the right half-ring 33. Although the material flow is accelerated on the right half-ring 33, the right half-ring 33 also has a third vent 31, and the central cylinder 2 has a second vent 21, so the material can also be heated by the hot air on the right half-ring 33. Moreover, since the spiral feed plate 3 includes multiple feed plate units, the material frequently switches between the left half-ring 32 and the right half-ring 33. That is, after being heated by high-temperature hot air on the left half-ring 32, the material enters the right half-ring 33 to be heated by lower-temperature hot air, and then enters the next left half-ring 32 for high-temperature heating, cycling in sequence to avoid the problem of uneven heating on one side of the material. Therefore, this application can achieve more uniform heating of materials, avoid a series of problems caused by uneven heating, and allow hot air to contact materials for a longer time to make full use of the energy of hot air, thereby improving the heat utilization rate of hot air and reducing energy consumption.
[0024] The upper surface of the flexible metal plate 34 is flush with the upper surface of the corresponding left half ring 32 and right half ring 33 at their joint. This prevents material from getting stuck when flowing through the flexible metal plate 34. A mounting cylinder 4 is coaxially sleeved outside the drying cylinder 1. The left and right sides of the mounting cylinder 4 are respectively provided with coaxial air inlets 41 and air outlets 42. The air inlets 41 are connected to the pipes of the hot air generator, and the air outlets 42 are connected to the exhaust pipes.
[0025] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.
Claims
1. A grain dryer, characterized in that, include: The drying drum has a vertical axis, a feed inlet at the top and a discharge outlet at the bottom, and first ventilation holes are evenly distributed on its drum wall. The hot air generator is set in the left-right direction and blows hot air onto the drying cylinder from left to right. The central cylinder is located inside the drying cylinder and is coaxial with the drying cylinder. Its cylinder wall has evenly distributed second air vents and its upper end has a cap. A spiral feeder plate is set in the annular space between the drying cylinder and the central cylinder. The spiral feeder plate is provided with a third vent hole. The spiral feeder plate includes multiple feeder plate units. The vertical projection of each feeder plate unit is a circle. Each feeder plate unit includes a left half ring and a right half ring connected by a flexible metal plate. The right half ring is fixedly connected to the drying cylinder and the central cylinder respectively. The left half ring is slidably engaged with the drying cylinder and the central cylinder respectively. A support part is provided on the inner wall of the left side of the drying cylinder. An elastic buffer column is set on the support part to abut against the lower surface of the left half ring. A vibrator is also installed on the lower surface of the left half ring. The spiral helix angle of the right half ring is greater than that of the left half ring. After the vibrator is started, it can drive the left half ring to vibrate, so that the material on it will slowly move downward.
2. A grain dryer according to claim 1, characterized in that, The upper surface of the spiral feed plate has multiple small steps that descend in sequence to promote material tumbling.
3. A grain dryer according to claim 1, characterized in that, The upper surface of the spiral feeder plate is evenly distributed with multiple guide ribs. The guide ribs extend downward at an angle from near the central cylinder to near the drying cylinder to guide the material toward the drying cylinder.
4. A grain dryer according to claim 1, characterized in that, The upper surface of the flexible metal plate is flush with the upper surface of the corresponding left and right half-ring joint.
5. A grain dryer according to claim 1, characterized in that, An installation cylinder is coaxially fitted around the drying cylinder. The left and right sides of the installation cylinder are respectively provided with coaxial air inlets and air outlets. The air inlets are connected to the pipes of the hot air generating device, and the air outlets are connected to the exhaust pipes.
6. A grain dryer according to claim 1, characterized in that, The cap has a cone-shaped structure that is smaller at the top and larger at the bottom.
7. A grain dryer according to claim 1, characterized in that, The feed inlet is equipped with a flared structure.