CN111735258B

CN111735258B - Grain cooling machine

Info

Publication number: CN111735258B
Application number: CN202010591256.XA
Authority: CN
Inventors: 林祥恩; 徐誉尘; 林朗
Original assignee: Taizhou Zhongsui Technology Co ltd
Current assignee: Taizhou zhongsui Technology Co.,Ltd.
Priority date: 2020-06-24
Filing date: 2020-06-24
Publication date: 2022-03-15
Anticipated expiration: 2040-06-24
Also published as: CN111735258A

Abstract

The invention discloses a grain cooling machine, which relates to the technical field of grain cooling machines, and adopts the technical scheme that the grain cooling machine comprises a lower box body and an upper box body; a condenser is fixed on the bottom surface of the upper box body; an air inlet is formed in one side of the lower box body, and a valve device is embedded in the air inlet; an air outlet fan is embedded in the lower box body at the side adjacent to the air inlet; an adjusting mechanism is arranged in the lower box body; the adjusting mechanism comprises a fixed shaft, a third bevel gear, a rotating circular pipe and a first L shaft; one end of the first L shaft, which is far away from the rotating circular tube, is fixedly provided with a connecting tube, and a second L shaft penetrates through the connecting tube; a fourth bevel gear is fixed at one end of the second L shaft close to the third bevel gear; a driving lever is fixed at one end of the second L shaft, which is far away from the fourth bevel gear; a power assembly for driving the rotating circular tube to rotate is arranged in the lower box body; and a second driving device for driving the air outlet fan to start is arranged in the lower box body. The invention solves the problem of low working efficiency of a single motor and achieves the effect of improving the working efficiency of the motor.

Description

Grain cooling machine

Technical Field

The invention relates to the technical field of grain coolers, in particular to a grain cooler.

Background

At present, grain coolers are mainly used in granaries, storage depots and the like for reducing the air temperature in the granary.

In the prior art, reference may be made to chinese patent with publication number CN103141571B, which discloses a single-cooling type water source heat pump grain cooling unit, comprising a unit box, an air mixing box installed at the front end of the unit box, an air return connection pipe installed at the first inlet end of the air mixing box, and a fresh air inlet end fixed at the second inlet end of the air mixing box. An electric return air valve is arranged in the return air connecting pipe. Install the new trend motorised valve in the new trend entrance point of mixing bellows, the coarse filter is installed to the exit end of mixing bellows, coarse filter and air cooler's entrance connection, air cooler's exit end and the entrance connection of collection tuber pipe, the exit end of collection tuber pipe and the access connection who directly links centrifugal fan.

However, the fresh air electric valve and the fan are controlled by different motors, so that the air inlet and outlet operations can be completed only by starting the two motors at the same time; when only a single motor is turned on or off, the cooler cannot work normally, so that the working efficiency of the single motor is low.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a grain cooling machine which achieves the effect of improving the working efficiency of a motor by arranging an adjusting mechanism.

The above object of the present invention is achieved by the following technical solutions:

a grain cooling machine comprises a lower box body and an upper box body fixed at the top of the lower box body; a condenser is fixed on the bottom surface of the upper box body; an air inlet is formed in one side of the lower box body, and a valve device is embedded in the air inlet; an air outlet fan is embedded in the lower box body at the side adjacent to the air inlet; an adjusting mechanism for driving the valve device or starting the air outlet fan is arranged in the lower box body; the adjusting mechanism comprises a fixed shaft fixed on the inner bottom surface of the lower box body, a third bevel gear fixed at the top end of the fixed shaft, a rotating circular pipe sleeved on the peripheral surface of the fixed shaft and a first L shaft fixed on the peripheral surface of the rotating circular pipe; a connecting pipe is fixed at one end of the first L shaft, which is far away from the rotating circular pipe, and a second L shaft penetrates through the connecting pipe; a fourth bevel gear meshed with the third bevel gear is fixed at one end, close to the third bevel gear, of the second L shaft; a driving lever is fixed at one end of the second L shaft, which is far away from the fourth bevel gear; a power assembly for driving the rotating circular tube to rotate is arranged in the lower box body; and a first driving device for driving the valve device to be opened and a second driving device for driving the air outlet fan to be started are arranged in the lower box body.

By adopting the technical scheme, the rotating round pipe drives the second L shaft to rotate through the first L shaft; because the third bevel gear is meshed with the fourth bevel gear, the second L shaft can also rotate in the rotating process by taking the third bevel gear as the circle center. The deflector rod drives the air outlet fan to start through the second driving device in the moving process of the second L shaft, and drives the valve device to open through the first driving device, so that gas entering the lower box body is conveniently discharged through the air outlet fan after being refrigerated. The air supply process is completed by a single motor, and the working efficiency of the motor is improved.

The present invention in a preferred example may be further configured to: the valve device comprises an annular box body embedded in an air inlet, two support bars fixed on the inner peripheral surface of the annular box body respectively, support columns fixed at the opposite ends of the two support bars, four rotating shafts uniformly distributed on the outer peripheral surfaces of the support columns and fan-shaped valves fixed on the outer peripheral surfaces of the four rotating shafts respectively; each rotating shaft is rotatably connected with the outer peripheral surface of the support column, and one end of each rotating shaft, which is far away from the support column, is rotatably connected with the inner peripheral surface of the annular box body; a first bevel gear is fixed at one end of each rotating shaft, which is far away from the supporting column; an annular cavity is formed in the annular box body, and a bevel gear ring meshed with the first bevel gear is rotatably arranged on the inner circumferential surface of the annular cavity.

By adopting the technical scheme, after one first bevel gear rotates, the bevel gear ring can be driven to rotate, and the bevel gear ring rotates and drives the other three first bevel gears to rotate. The four first bevel gears respectively drive the rotating shafts to rotate, and the rotating shafts can drive the valves to be opened when rotating, so that air can be conveniently fed into the air inlets. Through setting up valving, reduce the possibility that cereal cooler debris got into cereal cooler when stop work, improve cereal cooler's life.

The present invention in a preferred example may be further configured to: the first driving device comprises a driving shaft fixed at the bottom of the first bevel gear, two first springs fixed on the outer peripheral surface of the annular box body and a first connecting plate fixed at the bottom ends of the two first springs; a rotating pipe is fixed at the top of the first connecting plate; and a rotating assembly used for driving the driving shaft to rotate is arranged between the driving shaft and the rotating pipe.

By adopting the technical scheme, when the deflector rod is pressed downwards against the first connecting plate, the first connecting plate drives the rotating pipe to move downwards; the rotating tube drives the rotating shaft to rotate through the rotating assembly. The rotating shaft drives the first bevel gear connected with the rotating shaft to rotate, so that the valve device is opened and closed, and is convenient to control through the adjusting mechanism.

The present invention in a preferred example may be further configured to: the rotating assembly comprises five spiral bulges which are uniformly distributed on the peripheral surface of the driving shaft along the circumferential direction of the rotating shaft and five spiral grooves which are uniformly distributed on the inner peripheral surface of the rotating pipe along the circumferential direction of the rotating pipe; each of the helical projections is engaged with the helical groove.

Through adopting above-mentioned technical scheme, the rotating tube removes the in-process, and the heliciform recess supports downwards and presses the heliciform arch to apply the rotation moment of torsion to the heliciform arch, therefore drive the axis of rotation and rotate. Through setting up rotating assembly, be convenient for support downwards through the driving lever and press first connecting plate, realize opening of valve device.

The present invention in a preferred example may be further configured to: the second driving device comprises a vertical plate fixed on the inner bottom surface of the lower box body, a mounting box fixed on one side of the vertical plate close to the air outlet fan, two supporting pieces fixed on the inner bottom surface of the mounting box, two connecting shafts respectively rotatably mounted on the opposite inner sides of the two supporting pieces, two internal thread holes respectively formed in the opposite inner sides of the two connecting shafts, and two threaded shafts respectively in threaded connection with the two internal thread holes; a guide assembly for driving the threaded shaft to move along the length direction of the mounting box is arranged between each threaded shaft and the side wall of the mounting box; a switch stator and a switch rotor are respectively fixed at the opposite ends of the two threaded shafts; a first lead and a second lead are respectively arranged in the two threaded shafts in a penetrating manner; the switch stator is electrically connected with a first lead, and one end of the first lead, which is far away from the switch stator, is electrically connected with a power supply; the switch moving piece is electrically connected with a second wire, and one end of the second wire, which is far away from the switch moving piece, is electrically connected with the air outlet fan; and two groups of driving mechanisms for driving the connecting shaft to rotate are arranged in the mounting box.

By adopting the technical scheme, after the two connecting shafts rotate respectively, the two connecting shafts drive the threaded shafts to move oppositely; after the two threaded shafts move to be in contact with each other, the switch moving piece and the switch fixed piece are closed, so that the power supply and the air outlet fan are in a conducting state; after the power supply supplies power to the air outlet fan, the air outlet fan is started, so that cold airflow in the lower box body is discharged.

The present invention in a preferred example may be further configured to: each group of driving mechanisms comprises a transmission gear fixed on the peripheral surface of the connecting shaft, a second spring fixed on the inner top surface of the mounting box and a rack fixed at the bottom end of the second spring and used for being meshed with the transmission gear; a second connecting plate is fixed at the bottoms of the two racks; and a second connecting sheet which is used for being abutted against the shifting lever is fixed on one side of the second connecting plate, which is close to the fixed shaft.

By adopting the technical scheme, after the deflector rod is downwards abutted against the second connecting plate, the second connecting plate drives the two racks to downwards move, and the rack drives the transmission gear to rotate in the moving process, so that the two connecting shafts rotate. The connecting shaft can drive the threaded shaft to move after rotating, so that the switch moving piece is separated from the switch fixed piece. Because the driving lever is in the closed state with the second connecting plate during butt, valve device realizes closing of air-out fan simultaneously, realizes controlling air-out fan and valve device through single motor, improves the work efficiency of motor.

The present invention in a preferred example may be further configured to: each group of guide assemblies comprises a guide sheet fixed on the outer peripheral surface of the threaded shaft, an installation through hole formed in the side wall of the installation box and a guide groove formed in the inner peripheral surface of the installation through hole; the guide sheet is arranged in the guide groove in a sliding mode along the axial direction of the installation through hole.

Through adopting above-mentioned technical scheme, the guide way provides the guide effect for the guide plate, reduces the threaded shaft along the installation through-hole axial displacement in-process possibility of deviating from the track.

The present invention in a preferred example may be further configured to: the power assembly comprises a motor fixed on the inner bottom surface of the lower box body, a fifth bevel gear fixed on the output end of the motor and a sixth bevel gear fixed on the peripheral surface of the rotating circular tube and meshed with the fifth bevel gear.

Through adopting above-mentioned technical scheme, the motor rotates and drives fifth bevel gear and rotates, and fifth bevel gear passes through sixth bevel gear and drives the rotation pipe and rotate to provide power for the rotation of driving lever.

In summary, compared with the prior art, the invention has the following beneficial effects:

1. the adjusting mechanism drives the air outlet fan to start through the second driving device, and drives the valve device to open through the first driving device, so that gas entering the lower box body is conveniently discharged through the air outlet fan after being refrigerated. The air supply process is completed by a single motor, so that the working efficiency of the motor is improved;

2. by arranging the valve device, the possibility that sundries enter the grain cooler when the grain cooler stops working is reduced, and the service life of the grain cooler is prolonged;

3. because the driving lever is in the closed state with the second connecting plate during butt, valve device realizes closing of air-out fan simultaneously, realizes controlling air-out fan and valve device through single motor, improves the work efficiency of motor.

Drawings

FIG. 1 is a partial cross-sectional view of an embodiment of the present invention;

FIG. 2 is a partial cross-sectional view of the highlighted valve arrangement of the present invention;

fig. 3 is an enlarged schematic view of a portion a of fig. 1.

In the figure: 1. an upper box body; 11. a condenser; 12. an air inlet; 13. an air outlet fan; 14. a lower box body; 15. a motor; 16. a fifth bevel gear; 17. a sixth bevel gear; 18. an internally threaded bore; 2. a valve means; 21. an annular box body; 22. a supporting strip; 23. a support pillar; 24. a rotating shaft; 25. a fan-shaped valve; 26. a first bevel gear; 27. an annular cavity; 28. a conical gear ring; 3. a first driving device; 31. a drive shaft; 32. a first spring; 33. a first connecting plate; 34. rotating the tube; 35. a helical protrusion; 36. a second connecting sheet; 4. a second driving device; 41. a vertical plate; 42. mounting a box; 43. a support member; 44. a connecting shaft; 45. a power source; 46. a threaded shaft; 47. a transmission gear; 48. a second spring; 49. a rack; 5. a guide assembly; 51. a guide piece; 52. mounting a through hole; 53. a guide groove; 54. a first conductive line; 55. a second conductive line; 56. a second connecting plate; 6. an adjustment mechanism; 61. a fixed shaft; 62. a third bevel gear; 63. rotating the circular tube; 64. a first L axis; 65. a connecting pipe; 66. a second L axis; 67. a fourth bevel gear; 68. a deflector rod; 69. a first connecting piece.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Example (b): a grain cooler, as shown in FIG. 1, includes a lower tank 14 and an upper tank 1 fixed to the top of the lower tank 14. A condenser 11 is fixed on the bottom surface of the upper box body 1. An air inlet 12 is formed at one side of the lower box 14. The air inlet 12 is embedded with a valve device 2. An air outlet fan 13 is embedded in the lower box body 14 and the side adjacent to the air inlet 12. The lower box 14 is internally provided with a first driving device 3 for driving the valve device 2 to open and a second driving device 4 for driving the air outlet fan 13 to start.

As shown in fig. 1 and 2, the valve device 2 includes an annular box 21 embedded in the air inlet 12, two supporting bars 22 fixed to the inner peripheral surface of the annular box 21, supporting columns 23 fixed to opposite ends of the two supporting bars 22, four rotating shafts 24 uniformly distributed on the outer peripheral surface of the supporting columns 23, and fan-shaped valves 25 fixed to the outer peripheral surfaces of the four rotating shafts 24. Each rotating shaft 24 is rotatably connected with the outer peripheral surface of the supporting column 23, and one end of each rotating shaft 24, which is far away from the supporting column 23, is rotatably connected with the inner peripheral surface of the annular box body 21. A first bevel gear 26 is fixed at one end of each rotating shaft 24 far away from the supporting column 23; an annular cavity 27 is formed in the annular box body 21, and a bevel gear ring 28 meshed with the first bevel gear 26 is rotatably mounted on the inner circumferential surface of the annular cavity 27. After one of the first bevel gears 26 rotates, the bevel gear ring 28 is driven to rotate, and the bevel gear ring 28 rotates to drive the other three first bevel gears 26 to rotate. The four first bevel gears 26 respectively drive the rotation shafts 24 to rotate, and the rotation shafts 24 drive the valves to open when rotating, thereby facilitating air intake into the air inlet 12.

As shown in fig. 2, the first driving means 3 includes a driving shaft 31 fixed to the bottom of one of the first bevel gears 26, two first springs 32 fixed to the outer circumferential surface of the ring-shaped case 21, and a first connecting plate 33 fixed to the bottom ends of the two first springs 32. A rotating pipe 34 is fixed on the top of the first connecting plate 33. Five spiral protrusions 35 are uniformly distributed on the outer peripheral surface of the driving shaft 31 along the circumferential direction of the rotating shaft 24, and five spiral grooves are uniformly distributed on the inner peripheral surface of the rotating pipe 34 along the circumferential direction of the rotating pipe 34; each helical projection 35 engages with a helical groove. After the first connecting plate 33 is forced to move downwards, the first connecting plate 33 drives the rotating pipe 34 to move downwards; during movement of the rotating tube 34, the helical groove presses down against the helical protrusion 35, thereby applying a rotational torque to the helical protrusion 35, thereby rotating the rotating shaft 24. The rotating shaft 24 rotates a first bevel gear 26 connected thereto.

As shown in fig. 1 and 3, the second driving device 4 includes a vertical plate 41 fixed to the inner bottom surface of the lower case 14, a mounting box 42 fixed to a side of the vertical plate 41 close to the air outlet fan 13, two supporting members 43 fixed to the inner bottom surface of the mounting box 42, two connecting shafts 44 rotatably mounted to opposite inner sides of the two supporting members 43, two internal thread holes 18 respectively opened to opposite inner sides of the two connecting shafts 44, and two threaded shafts 46 respectively threadedly coupled to the two internal thread holes 18. A guide assembly 5 for driving the threaded shaft 46 to move along the length direction of the mounting box 42 is arranged between each threaded shaft 46 and the side wall of the mounting box 42. Each set of guide members 5 includes a guide piece 51 fixed to the outer peripheral surface of the threaded shaft 46, a mounting through hole 52 opened in the side wall of the mounting box 42, and a guide groove 53 opened in the inner peripheral surface of the mounting through hole 52. The guide piece 51 is slidably disposed in the guide groove 53 in the axial direction along the mounting through hole 52. The opposite ends of the two threaded shafts 46 are respectively fixed with a switch stator and a switch rotor; a first lead 54 and a second lead 55 are respectively arranged in the two threaded shafts 46; the switch stator is electrically connected with a first lead 54, and one end of the first lead 54, which is far away from the switch stator, is electrically connected with the power supply 45; the switch rotor is electrically connected with the second wire 55, and one end of the second wire 55, which is far away from the switch rotor, is electrically connected with the air outlet fan 13. After the two connecting shafts 44 rotate respectively, the two connecting shafts 44 drive the threaded shafts 46 to move oppositely; after the two threaded shafts 46 move to contact with each other, the switch moving piece and the switch fixed piece are closed, so that the power supply 45 and the air outlet fan 13 are in a conducting state; after the power supply 45 supplies power to the air outlet fan 13, the air outlet fan 13 is started, so that the cold airflow in the lower box 14 is discharged.

As shown in fig. 1 and 3, a transmission gear 47 is fixed to an outer peripheral surface of each connecting shaft 44; two second springs 48 are fixed on the inner top surface of the mounting box 42, and a rack 49 for meshing with the transmission gear 47 is fixed at the bottom end of each second spring 48. The second connecting plate 56 is fixed at the bottom of the two racks 49. An adjusting mechanism 6 for driving the second connecting plate 56 or the first connecting plate 33 to move downwards is arranged between the second connecting plate 56 and the first connecting plate 33. The second connecting plate 56 is forced to move downwards, the second connecting plate 56 drives the two racks 49 to move downwards, and the racks 49 drive the transmission gear 47 to rotate in the moving process, so that the two connecting shafts 44 rotate.

As shown in fig. 1 and 2, the adjusting mechanism 6 includes a fixed shaft 61 fixed to the inner bottom surface of the lower case 14, a third bevel gear 62 fixed to the top end of the fixed shaft 61, a rotating circular tube 63 fitted around the outer circumferential surface of the fixed shaft 61, and a first L-axis 64 fixed to the outer circumferential surface of the rotating circular tube 63. A connecting pipe 65 is fixed at one end of the first L-shaft 64 far away from the rotating circular pipe 63, and a second L-shaft 66 penetrates through the connecting pipe 65. A fourth bevel gear 67 meshed with the third bevel gear 62 is fixed at one end, close to the third bevel gear 62, of the second L-shaft 66; a shift lever 68 is fixed to the end of the second L-shaft 66 remote from the fourth bevel gear 67. A first connecting piece 69 for abutting against the shift lever 68 is fixed to the first connecting plate 33 on the side close to the fixed shaft 61. The second connecting plate 56 has a second connecting piece 36 fixed to a side thereof close to the fixed shaft 61 for abutting against the shift lever 68. A motor 15 is fixed on the inner bottom surface of the lower box body 14, and a fifth bevel gear 16 is fixed at the output end of the motor 15. A sixth bevel gear 17 for meshing with the fifth bevel gear 16 is fixed to the outer peripheral surface of the rotating circular tube 63. The motor 15 drives the fifth bevel gear 16 to rotate, and the fifth bevel gear 16 drives the sixth bevel gear 17 to rotate. The sixth bevel gear 17 rotates the rotating circular tube 63. The rotating round tube 63 drives the second L-shaft 66 to rotate through the first L-shaft 64; since the third bevel gear 62 is meshed with the fourth bevel gear 67, the second L-axis 66 also rotates during the rotation around the third bevel gear 62. The shift lever 68 contacts the first connecting piece 69 or the second connecting piece 36 during the movement of the second L-axis 66, and the shift lever 68 pushes the first connecting piece 69 or the second connecting piece 36 downward to drive the first connecting plate 33 or the second connecting plate 56 to move downward.

The working principle of the embodiment is as follows:

after the first connecting plate 33 is pressed by the shift lever 68 to move downwards, the first connecting plate 33 drives the rotating pipe 34 to move downwards; during movement of the rotating tube 34, the helical groove presses down against the helical protrusion 35, thereby applying a rotational torque to the helical protrusion 35, thereby rotating the rotating shaft 24. The rotating shaft 24 rotates a first bevel gear 26 connected thereto. Rotation of the first bevel gear 26 causes rotation of the bevel ring gear 28, which causes rotation of the bevel ring gear 28 and rotation of the remaining three first bevel gears 26. The four first bevel gears 26 respectively drive the rotation shafts 24 to rotate, and the rotation shafts 24 drive the valves to open when rotating, thereby facilitating air intake into the air inlet 12.

After the second connecting plate 56 is moved upward by the elastic force of the second spring 48, the second connecting plate 56 drives the two racks 49 to move downward, and the racks 49 drive the transmission gear 47 to rotate during the movement, so that the two connecting shafts 44 rotate. After the two connecting shafts 44 rotate respectively, the two connecting shafts 44 drive the threaded shafts 46 to move oppositely; after the two threaded shafts 46 move to contact with each other, the switch moving piece and the switch fixed piece are closed, so that the power supply 45 and the air outlet fan 13 are in a conducting state; after the power supply 45 supplies power to the air outlet fan 13, the air outlet fan 13 is started, so that the cold airflow in the lower box 14 is discharged.

The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.

Claims

1. A grain cooler comprises a lower box body (14) and an upper box body (1) fixed at the top of the lower box body (14); a condenser (11) is fixed on the bottom surface of the upper box body (1); air intake (12), its characterized in that have been seted up to lower box (14) one side: a valve device (2) is embedded in the air inlet (12); an air outlet fan (13) is embedded in the other side of the lower box body (14); an adjusting mechanism (6) for driving the valve device (2) or the air outlet fan (13) to be started is arranged in the lower box body (14); the adjusting mechanism (6) comprises a fixed shaft (61) fixed on the inner bottom surface of the lower box body (14), a third bevel gear (62) fixed at the top end of the fixed shaft (61), a rotating circular tube (63) sleeved on the outer peripheral surface of the fixed shaft (61), and a first L shaft (64) fixed on the outer peripheral surface of the rotating circular tube (63); a connecting pipe (65) is fixed at one end of the first L shaft (64) far away from the rotating circular pipe (63), and a second L shaft (66) penetrates through the connecting pipe (65); a fourth bevel gear (67) meshed with the third bevel gear (62) is fixed at one end, close to the third bevel gear (62), of the second L-shaft (66); a shift lever (68) is fixed at one end of the second L shaft (66) far away from the fourth bevel gear (67); a power assembly for driving the rotating round pipe (63) to rotate is arranged in the lower box body (14); a first driving device (3) for driving the valve device (2) to be opened and a second driving device (4) for driving the air outlet fan (13) to be started are arranged in the lower box body (14); the valve device (2) comprises an annular box body (21) embedded in the air inlet (12), two supporting strips (22) fixed on the inner peripheral surface of the annular box body (21) respectively, supporting columns (23) fixed at the opposite ends of the two supporting strips (22), four rotating shafts (24) uniformly distributed on the outer peripheral surface of the supporting columns (23) and fan-shaped valves (25) fixed on the outer peripheral surfaces of the four rotating shafts (24) respectively; each rotating shaft (24) is rotatably connected with the outer peripheral surface of the supporting column (23), and one end, far away from the supporting column (23), of each rotating shaft (24) is rotatably connected with the inner peripheral surface of the annular box body (21); one end of each rotating shaft (24) far away from the supporting column (23) is fixed with a first bevel gear (26); an annular cavity (27) is formed in the annular box body (21), and a bevel gear ring (28) meshed with the first bevel gear (26) is rotatably mounted on the inner circumferential surface of the annular cavity (27); the first driving device (3) comprises a driving shaft (31) fixed at the bottom of the first bevel gear (26), two first springs (32) fixed on the outer peripheral surface of the annular box body (21) and a first connecting plate (33) fixed at the bottom ends of the two first springs (32); a rotating pipe (34) is fixed at the top of the first connecting plate (33); a rotating assembly used for driving the driving shaft (31) to rotate is arranged between the driving shaft (31) and the rotating pipe (34); a first connecting plate (69) which is used for being abutted with the shifting lever (68) is fixed on one side, close to the fixed shaft (61), of the first connecting plate (33); the rotating assembly comprises five spiral bulges (35) which are uniformly distributed on the peripheral surface of the driving shaft (31) along the circumferential direction of the rotating shaft (24) and five spiral grooves which are uniformly distributed on the inner peripheral surface of the rotating pipe (34) along the circumferential direction of the rotating pipe (34); each helical projection (35) is engaged with the helical groove; the second driving device (4) comprises a vertical plate (41) fixed on the inner bottom surface of the lower box body (14), a mounting box (42) fixed on one side, close to the air outlet fan (13), of the vertical plate (41), two supporting pieces (43) fixed on the inner bottom surface of the mounting box (42), two connecting shafts (44) rotatably mounted on the opposite inner sides of the two supporting pieces (43) respectively, two internal thread holes (18) respectively formed in the opposite inner sides of the two connecting shafts (44) and two thread shafts (46) respectively in threaded connection with the two internal thread holes (18); a guide assembly (5) for driving the threaded shaft (46) to move along the length direction of the mounting box (42) is arranged between each threaded shaft (46) and the side wall of the mounting box (42); the opposite ends of the two threaded shafts (46) are respectively fixed with a switch stator and a switch rotor; a first lead (54) and a second lead (55) are respectively arranged in the two threaded shafts (46) in a penetrating way; the switch stator is electrically connected with a first lead (54), and one end, far away from the switch stator, of the first lead (54) is electrically connected with a power supply (45); the switch moving piece is electrically connected with a second lead (55), and one end, far away from the switch moving piece, of the second lead (55) is electrically connected with the air outlet fan (13); two groups of driving mechanisms for driving the connecting shaft (44) to rotate are arranged in the mounting box (42); each group of driving mechanisms comprises a transmission gear (47) fixed on the peripheral surface of the connecting shaft (44), a second spring (48) fixed on the inner top surface of the mounting box (42) and a rack (49) fixed at the bottom end of the second spring (48) and used for being meshed with the transmission gear (47); a second connecting plate (56) is fixed at the bottom of each of the two racks (49); and a second connecting piece (36) which is used for being abutted against the shifting rod (68) is fixed on one side of the second connecting plate (56) close to the fixed shaft (61).

2. The grain cooler according to claim 1, characterized in that: each group of guide assemblies (5) comprises a guide sheet (51) fixed on the outer peripheral surface of the threaded shaft (46), an installation through hole (52) formed in the side wall of the installation box (42) and a guide groove (53) formed in the inner peripheral surface of the installation through hole (52); the guide sheet (51) is arranged in the guide groove (53) in a sliding manner along the axial direction of the mounting through hole (52).

3. The grain cooler according to claim 1, characterized in that: the power assembly comprises a motor (15) fixed on the inner bottom surface of the lower box body (14), a fifth bevel gear (16) fixed at the output end of the motor (15) and a sixth bevel gear (17) fixed on the peripheral surface of the rotating circular pipe (63) and meshed with the fifth bevel gear (16).