Spiral conveying device for grain conveying

Abstract

The invention discloses a spiral conveying device for grain conveying, and belongs to the technical field of conveyors, the device comprises a machine shell, a rotating shaft, a driving assembly, a spiral blade and an air pipe sleeve, the machine shell is provided with a feeding port and a discharging port which are communicated with a working space, the machine shell is provided with a plurality of through holes, the working space is communicated with the air pipe sleeve through the through holes, and the rotating shaft is arranged in the air pipe sleeve. And the air pipe sleeve is connected with a first fan. When the first fan works, external airflow can be used for conducting air cooling on conveyed grains, the first fan is in full contact with grain particles in cooperation with stirring of the spiral blades, and the cooling effect is good; circulating airflow returns into the machine shell through the short connecting pipe to be matched with airflow entering from the bottom to conduct double air cooling on grain particles, and the overall energy consumption of grain cooling is low; when the electric heating pipe works, airflow entering from the bottom of the machine shell can be heated, conveyed grains are heated through the hot airflow, the hot airflow makes full contact with grain particles, and the temperature rising effect is good; heat conduction of the bottom wall is matched with double heating airflow, and the heating effect on the conveyed grains is good.

Description

Technical Field

[0001] The invention belongs to the technical field of conveyors, and in particular relates to a screw conveying device for conveying grain. Background Art

[0002] Screw conveyors are widely used in the field of grain storage. They can transport granular grains such as wheat, rice and sorghum from one link to another. For example, before the grain enters the dryer, it is generally transported to the dryer through a screw conveyor, or before it is stored in the warehouse, the grain is transported to the silo through a screw conveyor. Since the temperature of the grain affects the quality of the grain, if the grain temperature can be increased and the grain moisture can be reduced before entering the dryer, it will help improve the drying efficiency. If the grain temperature is reduced before entering the silo for storage, it will help extend the grain storage period and ensure the quality of the grain. If the existing screw conveyor needs to cool down or heat up the conveyed material during the conveying process, a jacket is usually set outside the casing. Cooling water can be passed into the jacket for cooling, and heating media such as heat transfer oil or steam can be passed into the jacket for heating. These cooling and heating methods all use tube wall contact heat exchange, which has low heat exchange efficiency. If the jacket leaks, the heat exchange medium will contaminate the grain after contacting with the grain, so it is not suitable for use in grain transportation. Summary of the invention

[0003] In view of the above problems existing in the prior art, the technical problem to be solved by the present invention is to provide a spiral conveying device for conveying grains, which can cool down or heat up grains during conveying.

[0004] Technical solution: In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0005] A spiral conveying device for conveying grains comprises a casing with a working space inside, a rotating shaft arranged in the casing, a driving assembly connected to the rotating shaft, spiral blades arranged on the rotating shaft, and an air duct sleeve arranged on the outer wall of the casing, wherein the casing is provided with a feed inlet and a discharge port connected to the working space, the casing is provided with a plurality of through holes, the working space is connected to the air duct sleeve through the through holes, and the air duct sleeve is connected to a first fan.

[0006] Preferably, a heat exchange shell is connected to the casing, a partition plate is provided in the heat exchange shell for dividing the space inside the heat exchange shell into a first heat exchange chamber and a second heat exchange chamber, a heat pipe is provided in the heat exchange shell, the heat pipe includes an evaporation section located in the first heat exchange chamber and a condensation section located in the second heat exchange chamber, a first connecting tube and a second connecting tube connected to the first heat exchange chamber are provided on the heat exchange shell, a third connecting tube and a fourth connecting tube connected to the second heat exchange chamber are provided on the heat exchange shell, the second connecting tube is connected to the third connecting tube through a second fan, the first connecting tube is connected to the end of the casing where the feed port is located, and the fourth connecting tube is connected to the end of the casing where the discharge port is located.

[0007] Preferably, an outer wall of the casing is provided with an electric heating tube, and the electric heating tube is located in the air duct sleeve.

[0008] Preferably, the outlet end of the second fan is connected to the casing through a short connecting pipe, the short connecting pipe is provided with a first stop valve, the third connecting pipe is provided with a second stop valve, and the fourth connecting pipe is provided with a third stop valve.

[0009] Preferably, the heat exchange shell is provided with a fifth connecting pipe and a sixth connecting pipe connected with the second heat exchange chamber, the fifth connecting pipe is connected to the third fan, the fifth connecting pipe is provided with a fourth stop valve, and the sixth connecting pipe is provided with a fifth stop valve.

[0010] Preferably, both the evaporation section and the condensation section are provided with fins.

[0011] Preferably, the casing includes a U-shaped shell and a cover plate detachably connected to the U-shaped shell.

[0012] Preferably, the feed port is connected to a feed hopper.

[0013] Preferably, the heat exchange shell is provided with a drain pipe connected to the first heat exchange cavity.

[0014] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0015] 1. An air duct sleeve is arranged on the outer wall of the casing, and a through hole connected to the air duct sleeve is arranged on the casing. The air duct sleeve is connected to the first fan. When the first fan is working, the external airflow can be used to cool the grain being transported. The stirring of the spiral blades can fully contact the grain particles, and the cooling effect is good;

[0016] 2. A heat exchange shell and a heat pipe are provided, and a second fan and a third fan are provided. When the grain being transported needs to be cooled, the second fan forms a circulating airflow, and the evaporation section of the heat pipe cools the circulating airflow. The circulating airflow returns to the casing through the short pipe and cooperates with the airflow entering from the bottom to double-cool the grain particles. The cooling effect is good, and the heat pipe does not require power supply, so the overall energy consumption of grain cooling is low;

[0017] 3. An electric heating tube is arranged on the outer bottom wall of the casing. When the electric heating tube is working, it can heat the airflow entering from the bottom of the casing, and use the hot airflow to heat the grains being transported, so that the hot airflow has sufficient contact with the grain particles and has a good heating effect;

[0018] 4. When it is necessary to heat the grain being transported, the second fan drives the circulating airflow to pass through the evaporation section and condensation section of the heat pipe in turn. The water content of the circulating airflow is reduced after passing through the evaporation section, and it is reheated after passing through the condensation section. The reheating energy consumption is low. The dry hot circulating airflow cooperates with the bottom hot airflow to contact the grain particles more fully, and the electric heating tube heats the bottom wall of the casing. The bottom of the casing contacts with the grain to transfer heat. The heat conduction of the bottom wall cooperates with the double heating airflow, which has a good heating effect on the grain being transported.

[0019] 5. The evaporation section reduces the moisture content of the circulating airflow and the moisture content of the grain during transportation, which is beneficial to the subsequent drying operation of the grain;

[0020] 6. The electric heating tube is located on the outer bottom wall of the casing and is arranged in the air duct sleeve. The electric heating tube is in a closed environment, with small heat loss and high heat energy utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present invention;

[0022] Figure 2 Schematic diagram of the structure of the housing, air duct sleeve and heat exchange shell of the embodiment;

[0023] Figure 3 Schematic diagram of the working principle of the heat pipe in the embodiment;

[0024] Figure 4 2. It is a schematic diagram of the heat exchange shell structure when heating grain in transportation according to the embodiment;

[0025] Figure 5 It is a schematic diagram of the heat exchange shell structure when cooling grain during transportation in an embodiment. DETAILED DESCRIPTION

[0026] The present invention is further illustrated below in conjunction with specific examples. The examples are implemented based on the technical solutions of the present invention. It should be understood that these examples are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0027] like Figure 1 and Figure 2 As shown, a spiral conveying device for conveying grains comprises a casing 1, a rotating shaft 2, a spiral blade 21, a driving assembly 3 and an air duct sleeve 4. The casing 1 is a U-shaped casing comprising a U-shaped casing 101 and a cover plate 102. The cover plate 102 covers the upper end of the U-shaped casing 101 and is detachably connected to the U-shaped casing 101. The detachable connection method can be an existing lock connection or a bolt connection. The casing 1 is hollow to form a working space. The rotating shaft 2 penetrates the casing 1 along the length direction of the casing 1. Both ends of the rotating shaft 2 are movably connected to the head and tail bearing seats. The head and tail bearing seats are connected to the outer wall of the casing 1, so that the rotating shaft 2 is supported. The driving assembly 3 is connected to the head end of the rotating shaft 2. The driving assembly 3 comprises a driving motor and The reducer and the driving component 3 drive the rotating shaft 2 to rotate when working. The spiral blade 21 is arranged on the outer wall of the rotating shaft 2 and extends along the length direction of the rotating shaft 2. When the rotating shaft 2 rotates, the spiral blade 21 is driven to rotate. The casing 1 is provided with a feed port 11 and a discharge port 12 connected to the working space. The feed port 11 is arranged at the head end of the casing 1 and is located at the upper part. The feed port 11 is connected to a feed hopper 111. The grain in the feed hopper 111 enters the working space of the casing 1 from the feed port 11, and gradually moves toward the rear end of the casing 1 driven by the spiral blade 21. The discharge port 12 is arranged at the rear end of the casing 1 and is located at the lower part. When the grain pushed by the spiral blade 21 reaches above the discharge port 12, it falls from the discharge port 12.

[0028] like Figure 1 and Figure 2 As shown, the air duct sleeve 4 is arranged on the outer wall of the casing 1 and sleeved on the lower half of the U-shaped casing 101. The arc-shaped bottom wall of the U-shaped casing 101 is provided with a plurality of through holes 13, and the plurality of through holes 13 are evenly arranged along the length direction of the casing 1. The working space is connected with the air duct sleeve 4 through the through holes 13, and the bottom of the air duct sleeve 4 is connected with the outlet end of the first fan 51 through a plurality of pipelines. When the grain needs to be cooled, the first fan 51 works, and the airflow enters the air duct sleeve 4 from the pipeline, and enters the working space in the casing 1 through the plurality of through holes 13, so as to fully contact with the grain particles driven by the spiral blades 21, and can use the external air to reduce the temperature of the grain in the casing 1, and play a role of air cooling. Moreover, since the airflow enters from the through holes 13 on the bottom wall, it fully contacts with the grain in the forward direction, and has a good cooling effect, which is suitable for cooling the grain while conveying before entering the storage bin, and the airflow in the working space is discharged through the discharge port 12 (the accumulation of grain in the feed hopper 111 will generate resistance, and the airflow will not go through the feed port 11).

[0029] like Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, a heat exchange shell 6 is connected to the casing 1, and the heat exchange shell 6 is arranged above the casing 1 and extends along the length direction of the casing 1. The heat exchange shell 6 is hollow, and a partition plate 601 is arranged in the middle position inside the heat exchange shell 6. The partition plate 601 divides the space inside the heat exchange shell 6 into a first heat exchange cavity 61 at the head end and a second heat exchange cavity 62 at the tail end. A heat pipe 7 is arranged in the heat exchange shell 6. The heat pipe 7 adopts a cylindrical heat pipe. The middle part of the heat pipe 7 passes through the partition plate 601. The heat pipe 7 includes an evaporation section 71 and a condensation section 72. The evaporation section 71 is located at In the first heat exchange cavity 61, the condensation section 72 is located in the second heat exchange cavity 62. A sintered liquid wick 702 is provided in the tube body of the heat pipe 7. There is a working fluid in the tube body of the heat pipe 7. The working fluid is water or methanol. When the evaporation section 71 of the heat pipe 7 is heated, the working fluid liquid in the liquid wick 702 evaporates and vaporizes. The steam flows to the condensation section 72 under a small pressure difference to release heat and condense into liquid. The liquid then flows back to the evaporation section 71 along the liquid wick 702 by capillary force, thus forming a cycle, and heat is transferred from the evaporation section 71 of the heat pipe 7 to the condensation section 72. The bottom of the heat pipe 7 is supported in the heat exchange shell 6 by a bracket. The bracket of the condensation section 72 is slightly higher. The heat pipe 7 is inclined. The height of the condensation section 72 is higher than the evaporation section 71. The gravity accelerates the reflux of the working fluid liquid. In order to improve the heat exchange effect between the heat pipe 7 and the air, fins 73 are provided on the evaporation section 71 and the condensation section 72. The fins 73 are in the shape of sheets. Multiple fins 73 are distributed in a circular array on the outer tube wall of the heat pipe 7. The fins 73 extend along the length direction of the heat pipe 7. The fins 73 can increase the heat exchange area and improve the heat exchange effect with the air.

[0030] like Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, the heat exchange shell 6 is provided with a first connecting pipe 63, a second connecting pipe 64, a third connecting pipe 65 and a fourth connecting pipe 66, the first connecting pipe 63 and the second connecting pipe 64 are connected to the first heat exchange chamber 61, and the first connecting pipe 63 is connected to the head end of the first heat exchange chamber 61, the second connecting pipe 64 is connected to the tail end of the first heat exchange chamber 61, the third connecting pipe 65 and the fourth connecting pipe 66 are connected to the second heat exchange chamber 62, and the third connecting pipe 65 is connected to the head end of the second heat exchange chamber 62, and the fourth connecting pipe 66 is connected to the tail end of the second heat exchange chamber 62, the second fan 52 is connected above the heat exchange shell 6, the second connecting pipe 64 is connected to the inlet end of the second fan 52, the third connecting pipe 65 is connected to the outlet end of the second fan 52, so that the second connecting pipe 64 is connected to the third connecting pipe 65 through the second fan 52, the first connecting pipe 63 is connected to the head end of the cover plate 102 near the position of the feed port 11, so as to communicate with the working space, and the fourth connecting pipe 66 is connected to the tail end of the cover plate 102, so as to communicate with the working space. A plurality of electric heating tubes 14 are arranged on the outer bottom wall of the U-shaped shell 101, the electric heating tube 14 is located in the air duct sleeve 4, the electric heating tube 14 is strip-shaped and arranged along the length direction of the U-shaped shell 101, the electric heating tube 14 adopts the existing dry-burning heating tube, and is made of high-resistance electric heating alloy wire, stainless steel and modified protactinium oxide powder and other materials, and is wrapped with stainless steel heat sink on the outside, with a large heat dissipation area, which can continuously heat the air for a long time. When the grain needs to be transported to the dryer for drying, the grain transported in the casing 1 is heated, the electric heating tube 14 starts to generate heat, the first fan 51 starts to work, and the airflow in the duct sleeve 4 passes through the electric heating tube 14 and is heated and then enters the working space in the casing 1 through multiple through holes 13. The hot air flow is in full contact with the grain particles, which can heat the grain particles and provide the temperature of the grain particles. At the same time, since the electric heating tube 14 is in contact with the bottom wall of the U-shaped shell 101, the bottom wall of the U-shaped shell 101 is also heated. When the grain particles move on the inner bottom wall of the U-shaped shell 101, they contact the inner bottom wall and there is also heat transfer. Under the dual heating of the inner bottom wall heating and the airflow heating, the temperature of the grain particles rises rapidly.

[0031] like Figure 1 , Figure 2 , Figure 4 and Figure 5As shown, when heating the food transported in the casing 1, the second fan 52 works, and the air in the casing 1 enters the first heat exchange chamber 61 from the first connecting pipe 63. The temperature of the hot air flow decreases after heat exchange with the evaporation section 71, and the moisture in the air flow condenses. A slope is provided at the bottom of the first heat exchange chamber 61, and a drain pipe 611 connected to the first heat exchange chamber 61 is provided on the heat exchange shell 6. The position of the drain pipe 611 corresponds to the lowest point of the slope. The water condensed on the fins 73 of the evaporation section 71 drips down and is discharged from the drain pipe 611, and the moisture content is reduced. The airflow after evaporation is discharged from the second connecting pipe 64 under the action of the second fan 52 and enters the second heat exchange chamber 62 from the third connecting pipe 65. When passing through the condensation section 72, it is heated by the condensation section 72, and the airflow temperature rises. The hot airflow returns to the working space in the casing 1 from the fourth connecting pipe 66. The inner wall of the cover plate 102 is provided with an airflow distribution pipe connected to the fourth connecting pipe 66, which is used to disperse the refluxed airflow. The returned hot airflow continues to heat the grain being transported. The airflow in the working space circulates from the first connecting pipe 63 into the heat exchange shell 6. The heat exchange shell 6 and the heat pipe 7 are provided to circulate the heated airflow and improve the heating effect of the grain particles in the working space. The evaporation section 71 can remove moisture from the airflow, which is beneficial to reduce the moisture content of the grain, reduce the moisture content of the grain entering the subsequent dryer, and improve the subsequent drying efficiency. The heat pipe 7 uses the heat of the front section of the circulating airflow to heat the airflow in the rear section, without the need for external heating equipment, which saves energy and reduces consumption.

[0032] like Figure 1 , Figure 2 , Figure 4 and Figure 5As shown, the outlet end of the second fan 52 is connected to the casing 1 through a short pipe 67, a first stop valve 81 is provided on the short pipe 67, a second stop valve 82 is provided on the third connecting pipe 65, a third stop valve 83 is provided on the fourth connecting pipe 66, a fifth connecting pipe 68 and a sixth connecting pipe 69 connected to the second heat exchange chamber 62 are provided on the heat exchange shell 6, the fifth connecting pipe 68 is arranged at the tail end of the heat exchange shell 6, a fourth stop valve 84 is provided on the fifth connecting pipe 68, the sixth connecting pipe 69 is connected to the third connecting pipe 65, a fifth stop valve 85 is provided on the sixth connecting pipe 69, the tail end of the casing 1 is connected to the third fan 53, and the fifth connecting pipe 68 is connected to the outlet end of the third fan 53. When the grain is cooled, the second fan 52 and the third fan 53 work, the first stop valve 81 is opened, the second stop valve 82 and the third stop valve 83 are closed, the fourth stop valve 84 and the fifth stop valve 85 are opened, and the air in the working space of the casing 1 enters the first heat exchange chamber 61 from the first connecting pipe 63. The temperature of the hot air flow decreases after heat exchange with the evaporation section 71. Under the action of the second fan 52, the air flow with the lowered temperature returns to the working space of the casing 1 from the short pipe 67, and circulates to cool the grain in transit. Cooperating with the air flow entering the casing 1 through the bottom through hole 13, the cooling effect on the grain is good and the energy consumption is low. When the third fan 53 is working, the external air flow enters the second heat exchange chamber 62 to cool the condensation section 72, and is discharged from the sixth connecting pipe 69 after heat exchange.

[0033] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A spiral conveying device for conveying grain, It is characterized in that The invention comprises a casing (1) with a working space inside, a rotating shaft (2) arranged in the casing (1), a driving assembly (3) connected to the rotating shaft (2), a spiral blade (21) arranged on the rotating shaft (2), and an air duct sleeve (4) arranged on the outer wall of the casing (1), wherein the casing (1) is provided with an inlet (11) and an outlet (12) connected to the working space, and the casing (1) is provided with a plurality of through holes (13), the working space is connected to the air duct sleeve (4) through the through holes (13), and the air duct sleeve (4) is connected to a first fan (51).

2. The spiral conveying device for conveying grain according to claim 1, It is characterized in that The casing (1) is connected to a heat exchange shell (6), the heat exchange shell (6) is provided with a partition plate (601) for dividing the space inside the heat exchange shell (6) into a first heat exchange chamber (61) and a second heat exchange chamber (62), the heat exchange shell (6) is provided with a heat pipe (7), the heat pipe (7) comprises an evaporation section (71) located in the first heat exchange chamber (61) and a condensation section (72) located in the second heat exchange chamber (62), the heat exchange shell (6) is provided with a second heat exchange chamber (61) in communication with the first heat exchange chamber (61), A connecting pipe (63) and a second connecting pipe (64); the heat exchange shell (6) is provided with a third connecting pipe (65) and a fourth connecting pipe (66) which are connected to the second heat exchange chamber (62); the second connecting pipe (64) is connected to the third connecting pipe (65) through a second fan (52); the first connecting pipe (63) is connected to the end of the shell (1) where the feed port (11) is located; and the fourth connecting pipe (66) is connected to the end of the shell (1) where the discharge port (12) is located.

3. The spiral conveying device for conveying grain according to claim 2, It is characterized in that An electric heating tube (14) is provided on the outer wall of the casing (1), and the electric heating tube (14) is located inside the air duct sleeve (4).

4. The spiral conveying device for conveying grain according to claim 2, It is characterized in that The outlet end of the second fan (52) is connected to the casing (1) via a short pipe (67); a first stop valve (81) is provided on the short pipe (67); a second stop valve (82) is provided on the third connecting pipe (65); and a third stop valve (83) is provided on the fourth connecting pipe (66).

5. The spiral conveying device for conveying grain according to claim 4, It is characterized in that The heat exchange shell (6) is provided with a fifth connecting pipe (68) and a sixth connecting pipe (69) which are connected to the second heat exchange chamber (62); the fifth connecting pipe (68) is connected to the third fan (53); the fifth connecting pipe (68) is provided with a fourth stop valve (84); and the sixth connecting pipe (69) is provided with a fifth stop valve (85).

6. The spiral conveying device for conveying grain according to claim 2, It is characterized in that The evaporation section (71) and the condensation section (72) are both provided with fins (73).

7. The spiral conveying device for conveying grain according to claim 1, It is characterized in that The housing (1) comprises a U-shaped housing (101) and a cover plate (102) detachably connected to the U-shaped housing (101).

8. The spiral conveying device for conveying grain according to claim 1, It is characterized in that The feed port (11) is connected to a feed hopper (111).

9. The spiral conveying device for conveying grain according to claim 2, It is characterized in that The heat exchange shell (6) is provided with a drainage pipe (611) which is in communication with the first heat exchange chamber (61).

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