A device for testing crop lodging resistance

Abstract

The present application discloses a device for testing the resistance of crops to lodging, comprising a centrifugal fan assembly (1), the centrifugal fan assembly (1) comprising a volute (11) fixed on a base (29), the volute (11) being provided with an air outlet (14) on a side close to the base (29), the air outlet (14) supplying air in a horizontal manner, a centrifugal blade being provided in the volute (11), the centrifugal blade being fixedly connected to a core blade drive shaft, an air inlet (13) being provided on a side of the volute away from the centrifugal blade drive shaft, and after adopting a centrifugal fan in the present application, the air outlet of the centrifugal fan is limited to be close to the bottom, so that an air supply effect consistent with natural wind is obtained in terms of air supply form.

Description

Technical Field

[0001] The invention relates to a testing device for crops, in particular to an air suction device used for testing the lodging resistance of crops. Background Art

[0002] Crop lodging is a phenomenon in which roots or stems are bent due to external forces. Taking corn as an example, corn lodging can usually be divided into stem breakage and root lodging. Stem breakage at or below the ear node is called stem breakage; root lodging is when the stem is at an angle of more than 30° to the vertical line without breaking (Beck et al., 1988). Some researchers also believe that root lodging occurs when the stem deviates from the vertical direction by more than 45° (Novacek et al., 2013). Wind is a direct external factor causing corn lodging. Li Shuyan et al. (2015) found that strong winds before and after the tasseling period can cause 86.0-98.5% of lodging. Corn root lodging often occurs in heavy rain and strong winds before the silking period. After the silking period, corn is mainly stem-broken, and most of it occurs in the internodes at the base under the ear. When corn lodging occurs before physiological maturity, it affects the grain filling rate and has a greater impact on yield; lodging after physiological maturity has less impact on corn yield, but increases the amount of ear drop during mechanical grain harvesting, reduces grain quality, increases harvesting difficulty, and significantly reduces harvesting efficiency and corn planting benefits.

[0003] Chinese patent application CN105699171A discloses a crop lodging resistance blowing test device, which includes an axial flow fan, a diffusion section, a stabilizing section, and a contraction section. The circular outlet of the axial flow fan is connected to the inlet of the diffusion section. The diffusion section is a circular-to-square section with a circular inlet and a square outlet. The inlet circle is the same size as the circular outlet of the axial flow fan. The square outlet of the diffusion section is connected to the inlet of the stabilizing section. The stabilizing section is a square straight cylinder section with the same caliber as the outlet caliber of the diffusion section. The outlet of the stabilizing section is connected to the inlet of the contraction section. The inlet of the contraction section is a rectangle of the same size as the outlet of the stabilizing section. The outlet of the contraction section is a rectangle with a width smaller than its own inlet width. The device can simulate natural wind to perform a lodging resistance blowing test on crops.

[0004] However, in actual use, it was found that the above equipment has many shortcomings:

[0005] 1) First of all, the air supply of this device cannot provide natural wind as it claims. Simulating natural wind is the most important part of crop testing. The axial flow fan used in the above patent application has basically the same wind force in the air supply section. However, in terms of actual field crop conditions, the applicant found that in many cases, the flow of wind in the crops is to creep between the crop plants close to the ground, while tributaries flow upward along the plants. This is related to the fact that the plants are planted in ridges and the leaves are more luxuriant the further upwards they go. It can be seen that the wind in the above patent application is not natural wind, and this axial flow air supply without wind force difference cannot test the actual lodging resistance of the crops.

[0006] 2) Secondly, the size of this device is too large to be easily transported, especially when conducting field tests in experimental fields. The equipment needs to be completely disassembled and transported to the site for reassembly. Moreover, the assembly is difficult, and the air duct structure is complex. If there is any carelessness during the assembly process, the air duct structure will deviate.

[0007] There has been no equipment in the prior art that is easy to install and maintain and can simulate natural wind to test the resistance of crops to lodging. Summary of the invention

[0008] The object of the present invention is to provide a device for testing the lodging resistance of crops which is easy to implement and can simulate natural wind.

[0009] A device for crop lodging resistance test, comprising a bracket assembly, on which a motor assembly and a centrifugal fan assembly are installed, and the motor assembly drives the centrifugal fan assembly to supply air; the bracket assembly comprises a base, on which a lower shell is supported by a plurality of supporting rods, and the lower shell, the upper shell, the first end cover and the second end cover jointly form an installation cavity to accommodate a centrifugal blade drive shaft; the motor assembly is detachably connected to the base and is transmission-connected to the centrifugal blade drive shaft through a pulley system; the centrifugal fan assembly comprises a volute fixed to the base, the volute is provided with an air outlet on the side close to the base, the air outlet supplies air in a horizontal air supply manner, a centrifugal blade is provided in the volute, the centrifugal blade is fixedly connected to the centrifugal blade drive shaft, the air inlet is provided on the side of the volute away from the centrifugal blade drive shaft, and also comprises a controller, and the motor assembly comprises a variable frequency motor, and the controller can adjust the rotation speed of the variable frequency motor to adjust the wind speed of the air supplied by the centrifugal fan assembly; the air outlet of the centrifugal fan assembly supplies air to the crops for lodging resistance test; a wind speed detector is used to detect the wind speed of the air supplied by the centrifugal fan assembly.

[0010] The air outlet is externally connected to an air flow diffuser, an inlet end of the air flow diffuser is connected to the air outlet, and the air flow diffuser is used to diffuse the horizontal wind supplied by the air outlet in the vertical direction.

[0011] The controller can compare the wind speed value obtained by the wind speed detector with the preset value, and adjust the speed of the variable frequency motor to adjust the actual air supply speed.

[0012] The upper edge of the exhaust port of the air flow diffuser is higher than the upper edge of the volute air outlet.

[0013] The motor seat of the motor assembly is detachably fixed to the base, and the base is also fixed with at least one adjustment seat. The adjustment bolt passes through the adjustment seat in a manner that the extension length of the thread can be adjusted, and the threaded end of the adjustment bolt abuts against the side of the motor seat.

[0014] A detachable side plate is provided on one side of the volute close to the centrifugal blade drive shaft, and the side plate is used to cover the maintenance hole. The centrifugal blade can be removed from the maintenance hole by only removing the side plate of the volute.

[0015] At least one thermometer is arranged on the upper surface of the upper shell.

[0016] A controller is also included, and the motor assembly includes a variable frequency motor, and the controller can adjust the rotation speed of the variable frequency motor.

[0017] At least one lifting ring is provided on the upper surface of the upper shell, the support rod and the motor assembly are arranged on one side of the base, the centrifugal fan assembly is arranged on the other side of the base, and the motor assembly is close to the side of the volute away from the air outlet of the volute.

[0018] The utility model also comprises a mobile trolley, which comprises a flat plate and wheel assemblies distributed on both sides of the flat plate. The flat plate is provided with positioning pins which match with the bracket assembly including the base.

[0019] Beneficial effects:

[0020] 1) First of all, the inventor first discovered that the flow direction of the wind in the test field is creeping wind close to the ground and tributary rising wind. Compared with the prior art, that is, compared with the equipment for anti-lodging test recorded in Chinese patent application CN105699171A, the present application uses a centrifugal fan instead of an axial flow fan, and the airflow is concentrated and discharged from the air outlet of the volute under the guidance of the wind duct in the volute. Since the air outlet of the present application is located on the lower side of the volute, the wind discharged from the air outlet is exactly similar to the form of creeping wind close to the ground of natural wind. After the present application adopts a centrifugal fan, the air outlet of the centrifugal fan is limited to be close to the bottom, and the air supply form unexpectedly obtains an air supply effect consistent with natural wind.

[0021] 2) In order to further simulate natural wind, the air outlet is connected to an air diffuser, the inlet end of which is connected to the air outlet, and the air diffuser is used to diffuse the horizontal wind supplied by the air outlet in the vertical direction. The diffused airflow is similar to the tributary between crops that rises from the airflow close to the ground. This further matches the form of natural wind.

[0022] 3) A detachable side panel is provided on the side of the volute close to the centrifugal blade drive shaft. The centrifugal blade can be removed from the maintenance hole by only removing the side panel of the volute 11. It is not necessary to destroy the overall structure of the volute, and the air duct structure is completely retained. Only the centrifugal blade needs to be replaced. Moreover, the component layout of the entire equipment is reasonable, the mass distribution is balanced, and the upper shell is selected as the fulcrum for lifting, so the whole machine can be lifted and moved. It is precisely because the equipment structure of the present application is compact and easy to move that the equipment of the present application is more convenient for transportation and lifting between test fields. The problems of repeated disassembly and assembly and poor reliability of the air duct structure in the prior art are eliminated.

[0023] 4) In addition, the equipment used for crop lodging resistance testing has a mobile device such as a trolley added to its bottom, which can be moved freely in the field to measure the lodging resistance of different corn varieties and cultivation conditions. It is precisely because the test equipment of this application has a compact structure that it is possible to move this equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present invention;

[0025] Figure 2 It is a side view of the overall structure of an embodiment of the present invention;

[0026] Figure 3 This is a view of the air outlet A in the embodiment of the present invention;

[0027] Figure 4 It is an enlarged view of the motor structure of an embodiment of the present invention;

[0028] Figure 5 A schematic diagram of the optimal embodiment of the overall structure of an embodiment of the present invention.

[0029] In the figure: centrifugal fan assembly 1, volute 11, side plate 12, air inlet 13, air outlet 14, reinforcing rib 15, bracket assembly 2, upper shell 21, lower shell 22, first end cover 23, second end cover 24, lifting ring 25, thermometer 26, support rod 27, protective shell 28, base 29, motor assembly 3, conveyor belt 31, adjustment seat 32, adjustment bolt 33, motor seat 34, air flow diffuser 4, inlet end 41, exhaust port 42, mobile trolley 5, flat plate 51, wheel assembly 52. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0032] See also Figure 1-4 , a device for crop lodging resistance test, including a bracket assembly 2, on which a motor assembly 3 and a centrifugal fan assembly 1 are installed, and the motor assembly 3 drives the centrifugal fan assembly 1 to supply air; the bracket assembly 2 includes a base 29, on which a lower shell 22 is supported by multiple support rods 27, and the lower shell 22, the upper shell 21, the first end cover 23 and the second end cover 24 together form an installation cavity to accommodate a centrifugal blade drive shaft; the motor assembly 3 is detachably connected to the base 29 and is transmission-connected to the centrifugal blade drive shaft through a pulley system; the centrifugal fan assembly 1 includes a volute 11 fixed to the base 29, and the volute 11 is provided with an air outlet 14 on the side close to the base 29, and the air outlet 14 supplies air in a horizontal air supply manner, and a centrifugal blade is arranged in the volute 11, and the centrifugal blade is fixedly connected to the centrifugal blade drive shaft, and the air inlet 13 is arranged on the side of the volute away from the centrifugal blade drive shaft.

[0033] Compared with the prior art, that is, compared with the equipment for lodging resistance test recorded in Chinese patent application CN105699171A, the present application uses a centrifugal fan instead of an axial flow fan. The centrifugal blades inhale the air flow from the air inlet of the volute and radially throw the wind out of the impeller under the action of high-speed rotation. The air flow is concentrated and discharged from the air outlet of the volute under the guidance of the wind duct in the volute. Since the air outlet of the present application is located on the lower side of the volute, the wind discharged from the air outlet is exactly similar to the form of natural wind creeping wind close to the ground. The centrifugal fan itself is a prior art, but after the present application adopts the centrifugal fan, the air outlet of the centrifugal fan is limited to be close to the bottom, and the air supply form unexpectedly obtains an air supply effect consistent with natural wind.

[0034] See attached Figure 5 In order to further simulate the natural wind, the air outlet is connected to an air diffuser, the inlet end of which is connected to the air outlet 14, and the air diffuser is used to diffuse the horizontal wind supplied by the air outlet in the vertical direction. Preferably, the upper edge of the exhaust port of the air diffuser is higher than the upper edge of the air outlet of the volute 11. The diffused airflow rises upward like a branch of the airflow between crops that is separated from the ground. This further matches the form of natural wind.

[0035] The motor seat 34 of the motor assembly 3 is detachably fixed to the base 29, and the base 29 is also fixed with at least one adjustment seat 32, and the adjustment bolt 33 passes through the adjustment seat 32 in a manner that the extension length of the thread can be adjusted, and the thread end of the adjustment bolt 33 abuts against the side of the motor seat 34. The purpose of adjusting the motor assembly 3 is to adjust the tension of the pulley assembly.

[0036] A detachable side plate 12 is provided on the side of the volute 11 close to the centrifugal blade drive shaft. The side plate 12 is used to cover the maintenance hole. The centrifugal blade can be removed from the maintenance hole by only removing the side plate 12 of the volute 11. The purpose of this design is that the overall structure of the volute 11 does not need to be destroyed, the air duct structure is completely retained, and only the centrifugal blade needs to be replaced.

[0037] At least one thermometer is disposed on the upper surface of the upper shell 21. The upper shell 21 is located on the back side of the air inlet of the volute 11 and away from the air outlet, so that the ambient temperature can be tested without being disturbed by the air flow.

[0038] A controller is also included, and the motor assembly 3 includes a variable frequency motor, and the controller can adjust the rotation speed of the variable frequency motor.

[0039] At least one lifting ring 25 is provided on the upper surface of the upper shell 21, the support rod 27 and the motor assembly 3 are arranged on one side of the base 29, the centrifugal fan assembly 1 is arranged on the other side of the base 29, and the motor assembly 3 is close to the volute 11 and away from the air outlet of the volute 11. The above structural layout distributes the gravity distribution between multiple structural components well, the centrifugal impeller of the centrifugal fan assembly 1 is close to the air outlet side, and the motor assembly 3 is arranged on the side away from the air outlet, so that the mass balance is achieved. On the other hand, the parallel arrangement of the centrifugal fan assembly 1 and the bracket assembly 2 also achieves a good mass distribution balance.

[0040] Example 1, taking the corn lodging resistance test as an example, the critical wind speed for lodging of corn under different density conditions was determined, and the relationship between planting density and critical wind speed for lodging was established, providing a basis for reasonable dense planting in different areas.

[0041] (1) Measurement process: Three samples were taken from each variety. The puncture strength of the third internode was first measured, and then the critical wind speed for lodging was measured.

[0042] (2) Method for determining the critical wind speed for corn lodging: Using the equipment for crop lodging resistance test described in the present application, the corn plants to be tested are clamped on a positioning frame at a predetermined density, and the positioning frame is placed on the air outlet side of the volute 11. The equipment for crop lodging resistance test is started and then the data is measured.

[0043] The distance between the plant and the air outlet is preferably 0.6m, and the anemometer is located 0.5m in front of the air outlet. The height of the plant and the height of the anemometer are adjusted so that the female ear is located 1.0m above the air outlet.

[0044] The controller is specifically a 0-50HZ manually adjustable frequency converter. The time it takes to rise from 0 to 50HZ is 80S, that is, the maximum wind speed can be reached in 80S.

[0045] Table 1 Critical wind speed for lodging and stem puncture strength at different planting densities

[0046]

[0047] Note: Different lowercase letters indicate significant differences at the 0.05 level for the same variety under different density conditions

[0048] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for testing crop lodging resistance, characterized in that: It comprises a bracket assembly (2), on which a motor assembly (3) and a centrifugal fan assembly (1) are mounted, and the motor assembly drives the centrifugal fan assembly to supply air; The support assembly (2) comprises a base (29), the base (29) supports a lower shell (22) via a plurality of support rods (27), the lower shell (22), the upper shell (21), the first end cover (23) and the second end cover (24) together form a mounting cavity for accommodating a centrifugal blade drive shaft; at least one lifting ring (25) is provided on the upper surface of the upper shell (21), the support rods (27) and the motor assembly (3) are arranged on one side of the base (29), the centrifugal fan assembly is arranged on the other side of the base (29), and the motor assembly (3) is close to the volute (11) and away from the air outlet of the volute (11); The motor assembly (3) is detachably connected to the base (29) and is drivingly connected to the centrifugal blade drive shaft via a pulley system; The centrifugal fan assembly (1) comprises a volute (11) fixed on a base (29), the volute (11) being provided with an air outlet (14) on a side close to the base (29), the air outlet (14) supplying air in a horizontal manner, the volute (11) being provided with centrifugal blades fixedly connected to a centrifugal blade drive shaft, the air inlet (13) being provided on a side of the volute away from the centrifugal blade drive shaft; the air outlet (14) being externally connected with an air flow diffuser, the air flow diffuser being used to diffuse the horizontal air supplied by the air outlet in a vertical direction, the inlet end of the air flow diffuser being connected to the air outlet (14), the cross-section of the air flow diffuser along the wind flow direction being trapezoidal, and the upper edge of the exhaust port thereof being higher than the upper edge of the air outlet of the volute; It also includes a controller, and the motor assembly (3) includes a variable frequency motor, and the controller can adjust the speed of the variable frequency motor to adjust the wind speed of the centrifugal fan assembly; The controller can compare the wind speed value obtained by the wind speed detector with the preset value, and adjust the speed of the variable frequency motor to adjust the actual air supply speed; The air outlet of the centrifugal fan assembly supplies air to the crops in the lodging resistance test; The wind speed detector is used to detect the wind speed of the air supplied by the centrifugal fan assembly.

2. The device for crop lodging resistance testing according to claim 1, characterized in that: The motor seat (34) of the motor assembly (3) is detachably fixed to the base (29), and the base (29) is also fixed with at least one adjustment seat (32). The adjustment bolt (33) passes through the adjustment seat (32) in a manner that the extension length of the thread can be adjusted, and the threaded end of the adjustment bolt (33) abuts against the side of the motor seat (34).

3. The device for crop lodging resistance testing according to claim 1, characterized in that: A detachable side plate (12) is provided on one side of the volute (11) close to the centrifugal blade drive shaft. The side plate (12) is used to cover the maintenance hole. The centrifugal blade can be removed from the maintenance hole by only removing the side plate (12) of the volute (11).

4. The device for crop lodging resistance testing according to claim 1, characterized in that: At least one thermometer is provided on the upper surface of the upper shell (21).

5. The device for crop lodging resistance testing according to claim 1, characterized in that: It also includes a positioning frame, on which the crops to be tested can be clamped, and the positioning frame is placed outside the air outlet of the volute (11).

6. The device for crop lodging resistance testing according to claim 1, characterized in that: The invention also comprises a mobile trolley, which comprises a flat plate and wheel assemblies distributed on both sides of the flat plate. The flat plate is provided with positioning pins which cooperate with the bracket assembly (2) including a base (29).

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