An online grain moisture detection device and method

Abstract

The application discloses an online grain moisture detection device and method, which comprises a rack, a volume standard mechanism installed on the rack, a horizontal conveying belt, a baffle, a stepping motor and a plurality of partitions, the stepping motor is connected with the horizontal conveying belt and drives the horizontal conveying belt to move, the baffle is located on both sides of the horizontal conveying belt, the plurality of partitions are arranged on the horizontal conveying belt and respectively enclosed with the baffle to form closed cavities, a microwave detector is installed above the volume standard mechanism, a quantitative feeding mechanism is connected with the volume standard mechanism through a material distributing mechanism, the material distributing mechanism is arranged in an inclined mode, and a controller is connected with the quantitative feeding mechanism, the material distributing mechanism, the stepping motor and the microwave detector respectively. The application further discloses an online grain moisture detection method.

Description

TECHNICAL FIELD

[0001] The present application relates to a grain detection technology, in particular to a microwave reflection type online grain moisture detection device and method. BACKGROUND

[0002] Due to the fact that the grain drying is not timely, the storage and transportation are not proper, and the grain moisture detection means is not perfect, about 10% of the grain is moldy and deteriorated during the storage and transportation process, resulting in huge losses. Therefore, it is important to quickly detect the moisture content of the grain in the process of grain purchase, storage, transportation, processing and trade, and it is of great significance to accurately measure it.

[0003] The existing grain moisture content measurement methods are divided into two categories: destructive detection and non-destructive detection. Destructive detection is a detection method in which the grain particles need to be crushed or the properties of the grain itself need to be changed during the detection process, resulting in the grain not being able to maintain its original form, structure or composition. Non-destructive detection is a method that analyzes the moisture content inside the grain without changing its state and chemical properties, by using the properties of the grain itself, such as physical properties, optical properties and chemical properties, to achieve the purpose of detecting the moisture content of the grain.

[0004] The standard method for grain moisture detection is the oven drying method, which is accurate but time-consuming, and is only suitable for laboratory detection of grain moisture, which cannot meet the requirements of online detection of grain moisture during storage in the grain depot. The capacitance method is the most commonly used method, which has simple device structure, high sensitivity, low cost, high measurement accuracy and does not require crushing of the grain. However, many factors can affect the measurement accuracy, such as the thickness of the material, temperature and season, etc. The near-infrared spectroscopy method is easy to realize continuous measurement and has a wide range of applications. However, this method can only be used for surface measurement and cannot measure the internal moisture distribution and its state. The hyperspectral technology can simultaneously obtain the spectral and image information of the measured moisture material, with high spectral resolution. However, this measurement method involves expensive equipment, so it is mainly used for laboratory measurement. The nuclear magnetic resonance method is fast, accurate and has a wide measurement range. However, due to the high cost of the instrument, high maintenance cost and the need for accurate calibration, it is currently mainly used for experimental research and moisture detection in the drying process of high-value-added products.

[0005] Due to the complexity of the influencing factors during the grain drying process, it is difficult to achieve online rapid measurement. In addition, it takes a certain amount of time to control the system after measuring the moisture content of the grain, which cannot meet the requirements of grain moisture measurement in the production and life process, resulting in waste of energy and not conducive to ensuring the drying of grain storage. SUMMARY

[0006] The technical problem solved by the present application is to provide an online grain moisture detection device and method to solve the above-mentioned defects of the prior art.

[0007] To achieve the above-mentioned purpose, the present application provides an online grain moisture detection device, comprising:

[0008] A rack;

[0009] A volume standard mechanism is installed on the rack, comprising a horizontal conveying belt, a baffle, a stepping motor and a plurality of partitions, the stepping motor is connected with the horizontal conveying belt and drives the horizontal conveying belt to move; the baffle is located on both sides of the horizontal conveying belt; the plurality of partitions are arranged on the horizontal conveying belt and respectively enclosed with the baffle to form a closed cavity;

[0010] A microwave detector is installed above the volume standard mechanism;

[0011] A quantitative feeding mechanism is connected with the volume standard mechanism through a material distributing mechanism, and the material distributing mechanism is inclinedly arranged; and

[0012] A controller is connected with the quantitative feeding mechanism, the material distributing mechanism, the stepping motor and the microwave detector respectively.

[0013] The online grain moisture detection device, wherein the online grain moisture detection device further comprises a grain unloading mechanism 7, comprising a receiving hopper and a proximity switch, the receiving hopper is installed on the rack and arranged corresponding to the grain outlet of the volume standard mechanism; the proximity switch is installed in the quantitative feeding mechanism near the grain outlet and connected with the controller.

[0014] The online grain moisture detection device, wherein the microwave detector comprises an installation top plate, a microwave transmitting probe, a microwave receiving probe, a bottom plate and a fixing plate, the installation top plate is connected with the rack; the fixing plate is symmetrically arranged on both sides of the installation top plate and respectively connected with the installation top plate and the bottom plate; the microwave transmitting probe and the microwave receiving probe are installed on the corresponding fixing plate; the bottom plate is provided with a microwave passage corresponding to the microwave transmitting probe and the microwave receiving probe.

[0015] The online grain moisture detection device, wherein the installation bottom surface of the microwave transmitting probe and the microwave receiving probe is attached to the fixing plate; the horn mouth of the microwave transmitting probe and the microwave receiving probe are both inward, and the included angle between the central axis of the microwave transmitting probe and the horizontal plane is 53°, and the included angle between the central axis of the microwave receiving probe and the horizontal plane is -53°.

[0016] The online grain moisture detection device, wherein the microwave passage is rectangular, the microwave emitted by the microwave emission probe reaches the surface of the grain sample to be detected through the microwave passage, and the microwave reflected by the surface of the grain sample to be detected is received by the microwave receiving probe through the microwave passage.

[0017] The online grain moisture detection device, wherein the quantitative feeding mechanism comprises a feeding bin, a photoelectric probe, a feeding motor, a rolling screw, a vertical slide rail and a sliding block; the feeding bin is installed on the rack; the rolling screw is connected with the feeding motor, the feeding motor is installed above the feeding bin through a horizontal support beam, and drives the rolling screw to rotate; the vertical slide rail is arranged in parallel with the rolling screw, the sliding block is installed on the rolling screw and connected with the vertical slide rail; the rolling screw drives the sliding block to move up and down along the vertical slide rail while rotating; the photoelectric probe is installed on the side of the sliding block and connected with the controller; the photoelectric probe horizontally emits a detection line and transmits a feedback signal to the controller.

[0018] The online grain moisture detection device, wherein the bottom of the feeding bin is provided with a pushing motor, a roller and a plurality of discharge blades corresponding to the distributing mechanism; the roller shaft is installed in cooperation with the shaft holes on both sides of the bottom of the feeding bin, one end of the roller shaft is connected with the pushing motor, and the pushing motor is connected with the controller; the discharge blades are uniformly distributed on the roller shaft.

[0019] The online grain moisture detection device, wherein the distributing mechanism comprises a roller conveyor belt, a distributing motor, side plates, a driving sprocket and a driven sprocket; the side plates are installed on both sides of the roller conveyor belt; the distributing motor is connected with the controller and the driving sprocket respectively; the driving sprocket is connected with the driven sprocket through a chain; and the roller conveyor belt is installed on the side plates and is driven by the chain.

[0020] The online grain moisture detection device, wherein the roller conveyor belt comprises rollers arranged in sequence and uniformly; the rollers are installed on the side plates through roller shafts; the roller shafts are connected with the chain; and the chain drives the roller shafts to rotate and drives the rollers to rotate.

[0021] The online grain moisture detection device, wherein the volume standard mechanism is further provided with a telescopic screed located below the distributing mechanism; the telescopic screed comprises a telescopic cylinder and a screed plate; one end of the telescopic cylinder is installed on the rack, and the other end of the telescopic cylinder is connected with the screed plate.

[0022] In order to better achieve the above purpose, the application further provides an online grain moisture detection method, which comprises the following steps:

[0023] S100, send the grain sample to be detected into a feeding bin, and detect the height value H of the upper surface of the grain sample to be detected to the bottom of the feeding bin by a photoelectric probe, and stop feeding the grain sample to the feeding bin when H reaches a height setting value;

[0024] S200, start the distributing mechanism, and rotate the roller to drive the grain sample to be detected to fall to a roller distributor, and the roller distributor uniformly sends the grain sample to be detected into a volume standard mechanism located on a horizontal conveying belt;

[0025] S300, when the grain sample to be detected completely falls into the volume standard mechanism, start the electric telescopic screed to level the surface of the grain sample to be detected, so that the grain sample to be detected uniformly fills the volume standard mechanism, and the thickness of each position of the grain sample to be detected is consistent;

[0026] S400, the microwave moisture detector detects the water content of the grain sample to be detected in the volume standard mechanism, and calculates the moisture content of the grain sample to be detected to obtain the grain water content;

[0027] S500, transmit the grain water content information to the controller, and display on the human-computer interaction interface; and

[0028] S600, the controller controls to open the unloading port of the volume standard mechanism, and sends the grain sample to be detected after detection into a receiving hopper, and completes the detection of the grain water content.

[0029] The technical effect of the present application is that:

[0030] The present application has good stability, high accuracy, and good repeatability for rapid real-time online grain moisture detection in the grain drying process.

[0031] The present application will be described in detail below in combination with the drawings and specific embodiments, but not as a limitation on the present application. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is a structural schematic diagram of an embodiment of the present application;

[0033] Figure 2 is a front view of Figure 1 ;

[0034] Figure 3 is a structural schematic diagram of a volume standard mechanism of an embodiment of the present application;

[0035] Figure 4 is a partial sectional view of a quantitative feeding mechanism of an embodiment of the present application;

[0036] Figure 5 Structure diagram of the microwave detector of an embodiment of the present application;

[0037] Figure 6 Structure diagram of the cloth mechanism of an embodiment of the present application.

[0038] Wherein, the reference signs

[0039] 1 frame

[0040] 2 quantitative feeding mechanism

[0041] 21 feeding bin

[0042] 22 feeding motor

[0043] 23 rolling screw

[0044] 24 discharging blade

[0045] 25 rolling wheel

[0046] 26 vertical slide rail

[0047] 261 sliding block

[0048] 27 pushing motor

[0049] 28 photoelectric probe

[0050] 29 horizontal support beam

[0051] 20 buzzer

[0052] 3 cloth mechanism

[0053] 31 side plate

[0054] 32 roller conveyor belt

[0055] 321 roller

[0056] 322 roller shaft

[0057] 33 chain

[0058] 34 cloth motor

[0059] 35 driving sprocket

[0060] 36 driven sprocket

[0061] 4 microwave detector

[0062] 41 fixed plate

[0063] 42 mounting top plate

[0064] 43 microwave emitting probe

[0065] 44 microwave receiving probe

[0066] 45 microwave port

[0067] 46 set screw

[0068] 5 volume standard mechanism

[0069] 51 horizontal conveyor belt

[0070] 52 stepper motor

[0071] 53 baffle

[0072] 54 partition

[0073] 55 screed

[0074] 56 telescopic cylinder

[0075] 6 controller

[0076] 7 unloading mechanism

[0077] 71 mounting beam

[0078] 72 receiving hopper

[0079] 73 proximity switch DETAILED DESCRIPTION

[0080] The structural principle and working principle of the present application will be described in detail below in combination with the drawings:

[0081] There are mainly two kinds of online moisture meters: one is a contact type online capacitive moisture meter, and the other is a non-contact type online microwave moisture meter. The contact type online capacitive moisture meter is mainly used for measuring grain media in the silo, and other working conditions basically adopt the non-contact type online microwave moisture meter. Microwave, as a very high frequency electromagnetic wave, has very strong penetration, and the moisture content of the material is calculated by using the change information of amplitude attenuation generated by microwave acting on the material. It not only detects the surface moisture of the grain, but also detects the internal moisture content of the grain without damage. Due to the changes and interference of grain thickness and environmental temperature, there are differences in the relative dielectric constant of the grain when detecting the moisture of the grain online, thereby affecting the precision of the moisture detection result.

[0082] Referring to Figures 1-3 , Figure 1 is a structural schematic diagram of an embodiment of the present application, Figure 2 is Figure 1 a front view, Figure 3The figure is a structural schematic diagram of the volume standard mechanism 5 of an embodiment of the present application. In view of the above problems, the present application provides an online grain moisture detection device, which comprises a rack 1, a volume standard mechanism 5 installed on the rack 1, a horizontal conveying belt 51, a baffle 53, a stepping motor 52 and a plurality of partitions 54, the stepping motor 52 is connected with the horizontal conveying belt 51 and drives the horizontal conveying belt 51 to move, the baffle 53 can be fixed on both sides of the horizontal conveying belt 51 by welding, the plurality of partitions 54 are arranged on the horizontal conveying belt 51 and respectively enclosed with the baffle 53 to form closed cavities, thereby realizing synchronous movement with the horizontal conveying belt 51, preferably three partitions 54 and two closed cavities are formed with the baffle 53 for receiving grain, the partitions 54 can be installed on the horizontal conveying belt 51 by screws, the height of the partition 54 is preferably 100 mm, a microwave detector 4 is installed above the volume standard mechanism 5, a quantitative feeding mechanism 2 is connected with the volume standard mechanism 5 through a distributing mechanism 3, the distributing mechanism 3 is arranged obliquely, and a controller 6, preferably an MCU controller 6, is connected with the quantitative feeding mechanism 2, the distributing mechanism 3, the stepping motor 52 and the microwave detector 4. The controller 6 can be connected with a man-machine interactive terminal through a power line and a signal line, adopts Modbus protocol to realize real-time communication with each mechanism, and the MCU controller 6 realizes accurate control of the quantitative feeding mechanism 2, the distributing mechanism 3, the volume standard mechanism 5, the microwave detector 4 and a grain unloading mechanism 7 through I / O port output control instructions and parameter setting signals. The horizontal conveying belt 51 rotates at a set speed, the microwave moisture detector above the horizontal conveying belt 51 is used to detect the moisture content of the grain in the volume standard mechanism 5, then the moisture content information of the grain is transmitted to the controller 6, and the moisture content value can be displayed on the man-machine interactive interface, finally the controller 6 sends an action signal to the electric switch to open the right end of the volume standard mechanism 5, so that the grain enters the receiving hopper 72, and the detection of the moisture content of the grain by the microwave moisture detection device is completed.

[0083] The man-machine interactive interface can be provided with two working modes, automatic and manual control modes can be selected for the user to select parameter setting, fault diagnosis and alarm system, process value trend and archived data storage, online operation, simulation operation and the like, and the running state of each mechanism of the device can be displayed in real time, the online detection process of the grain material moisture is intelligently monitored, is not easy to be disturbed by the outside world, the detection precision is significantly improved, the detection result fluctuation is small, the measurement error of the grain moisture detection is reduced, and the detection reliability and accuracy of the device are greatly improved.

[0084] The volume standard mechanism is also provided with a telescopic screed below the cloth mechanism, which comprises a telescopic cylinder 56 and a screed plate 55. One end of the telescopic cylinder 56 is installed on the frame, and the other end is connected with the screed plate 55. When the grain to be detected completely enters the volume standard mechanism 5, the controller 6 sends a control signal to the telescopic cylinder 56 to drive the screed plate 55 to move horizontally above the volume standard mechanism 5, so as to make the grain in the volume standard mechanism 5 uniform in thickness, avoiding the influence of the thickness of the grain on the moisture detection result during the detection process. The volume of the volume standard mechanism 5 is 20% different from the grain feeding amount, so as to avoid the loss caused by the spilling of the grain during the uniform cloth process. The thickness of the grain layer is controlled to be between 10-20 mm, and the relative error of the thickness of the grain layer is less than 10%. The rotating speed of the stepping motor 52 is controlled to be between 100 r / min-200 r / min, which can realize good synchronization with the cloth mechanism 3 and improve the effect of uniform cloth.

[0085] The sidewall of the feeding bin 21 is provided with four fixed threaded holes, and the feeding bin 21 is fixed by cooperation between the fixed screws and the threaded holes and the frame 1. The horizontal support beam 29 is fixed in the middle of the inlet plane of the feeding bin 21 by welding and is a rectangular iron sheet. The feeding motor 22 is installed in the middle of the horizontal support beam 29 by a fixed screw and drives the rotating screw rod 23 to rotate. The rotating screw rod 23 drives the sliding block 261 to move up and down along the vertical slide rail 26. The photoelectric probe 28 is installed on the side of the sliding block 261 by a fixed screw, and the photoelectric probe 28 horizontally emits a detection line to detect the height of the grain in the feeding bin 21 and transmits a control signal to the MCU controller 6. The buzzer 20 is installed on the left side of the horizontal support beam 29. When the height of the grain in the feeding bin 21 reaches the set height, the MCU controller 6 transmits a control instruction to control the buzzer 20 to prompt to stop feeding the grain into the feeding bin 21, so as to realize the quantitative feeding of the grain in the feeding bin 21. The roller shaft of the roller 25 cooperates with the shaft holes on both sides of the feeding bin 21. One side of the roller shaft is connected with the pushing motor 27 through a shaft coupling, and the rotating speed of the pushing motor 27 is controlled by the MCU controller 6. The rotating direction of the roller 25 is counterclockwise. The discharge blades 24 are fixed on the roller shaft by welding, and there are six discharge blades 24, which are responsible for pushing the grain to the cloth mechanism 3. The discharge port is rectangular and located below the roller 25.

[0086] The embodiment also includes a discharging mechanism 7, which comprises a receiving hopper 72 and a proximity switch 73. The receiving hopper 72 is installed on the frame 1 through a mounting support beam 7151 and is arranged corresponding to the grain outlet of the volume standardization mechanism 5. The proximity switch 73 is installed in the quantitative feeding mechanism 2 near the grain outlet and is connected with the controller 6. The proximity switch 73 can be installed on the inner side of the baffle 53 through a fixing screw and is located at the upper right side. When the rightmost partition plate 54 moves to the position directly below the proximity switch 73, the proximity switch 73 sends a signal to the MCU controller 6 and transmits a detection end signal to the microwave detector 4. The step motor 52 provides power for the volume standardization mechanism 5. The vertical distance between the volume standardization mechanism 5 and the rightmost end of the distributing mechanism 3 is preferably 200 mm. The horizontal conveying belt 51 conveys the grain in the volume standardization mechanism 5 to the position below the microwave detector 4 at a speed of 10-20 mm / s for moisture detection. When the right partition plate 54 of the standard volume mechanism moves to the proximity switch 73, the controller 6 transmits a control signal to the microwave detector 4 to stop working, and the horizontal conveying belt 51 continues to operate, so that the grain in the volume standardization mechanism 5 is continuously conveyed into the receiving hopper 72, and the moisture detection process of the grain is completed. During the process, the controller 6 changes the rotating speed of the step motor 52 to realize real-time adjustment of the discharging speed.

[0087] Referring to Figure 4 , Figure 4 Figure 2 is a partial sectional view of the quantitative feeding mechanism 2 according to an embodiment of the present application. The quantitative feeding mechanism 2 comprises a feeding bin 21, a photoelectric probe 28, a feeding motor 22, a rolling screw 23, a vertical slide rail 26 and a sliding block 261. The feeding bin 21 is installed on the frame 1. The rolling screw 23 is connected with the feeding motor 22. The feeding motor 22 is installed above the feeding bin 21 through a horizontal support beam 29 and drives the rolling screw 23 to rotate. The vertical slide rail 26 is arranged in parallel with the rolling screw 23. The sliding block 261 is installed on the rolling screw 23 and is connected with the vertical slide rail 26. The rolling screw 23 drives the sliding block 261 to move up and down along the vertical slide rail 26 while rotating. The photoelectric probe 28 is installed on the side of the sliding block 261 through a thread and is connected with the controller 6. The photoelectric probe 28 horizontally emits a detection line to generate a control feedback signal and transmits the feedback signal to the controller 6. A buzzer 20 can also be arranged in the feeding bin 21 and is connected with the controller 6. When the height of the grain in the feeding bin 21 reaches a set height, the controller 6 sends an instruction to control the buzzer 20 to prompt to stop feeding the grain into the feeding bin 21, so that the quantitative feeding of the grain in the feeding bin 21 is realized, and preparation for the volume standardization of the grain is made. Then, the controller 6 sends a control signal to the distributing motor 34 to prepare for the next step of grain distribution, so that the accurate control of the feeding process is realized.

[0088] In this embodiment, the bottom of the feeding bin 21 is provided with a pushing motor 27, a roller 25 and a plurality of discharge blades 24 corresponding to the distributing mechanism 3. The roller 25 is installed in cooperation with the shaft holes on both sides of the bottom of the feeding bin 21, one end of the roller is connected with the pushing motor 27, and the pushing motor 27 is connected with the controller 6. The discharge blades 24 are uniformly distributed on the roller. The discharge blades 24 quantitatively drive the grain to fall from the discharge port of the feeding bin 21 to the distributing mechanism 3 below, and at the same time, the roller-type distributing conveyor belt is driven by the distributing motor 34 to convey the grain to be measured to the volume standard mechanism 5 at a set speed, so as to realize uniform distribution of the grain to be measured.

[0089] Referring to Figure 5 , Figure 5The microwave detector 4 of the embodiment of the present application is shown in the structural schematic diagram. The microwave detector 4 of the embodiment comprises a mounting top plate 42, a microwave transmitting probe 43, a microwave receiving probe 44, a bottom plate and a fixing plate 41, the mounting top plate 42 is connected with the rack 1 through fixing screws 46; the fixing plate 41 is symmetrically arranged on both sides of the mounting top plate 42 and is connected with the mounting top plate 42 and the bottom plate respectively; the microwave transmitting probe 43 and the microwave receiving probe 44 are fixedly mounted on the corresponding fixing plate 41 through screws and are connected with the controller 6; the bottom plate is provided with microwave through holes 45 corresponding to the microwave transmitting probe 43 and the microwave receiving probe 44. Wherein, the mounting bottom surface of the microwave transmitting probe 43 and the microwave receiving probe 44 is attached to the fixing plate 41; the microwave transmitting probe 43 and the microwave receiving probe 44 are in the shape of a horn, the mounting bottom surface is coincident with the fixing plate 41, the horn mouths of the microwave transmitting probe 43 and the microwave receiving probe 44 are both inward, and the included angle between the central axis of the microwave transmitting probe 43 and the horizontal plane is 53°, the included angle between the central axis of the microwave receiving probe 44 and the horizontal plane is -53°. The microwave through hole 45 is rectangular, preferably rectangular, the length and the width are 150mm and 100mm respectively, in the detection process, the microwave transmitted by the microwave transmitting probe 43 reaches the surface of the grain sample to be detected through the microwave through hole 45, and the microwave receiving probe 44 receives the microwave reflected by the surface of the grain sample to be detected through the microwave through hole 45. When the horizontal conveying belt 51 drives the grain to pass below the microwave detector 4 at a set speed, the microwave will be attenuated, the probe can measure the change of the energy value, the microprocessor selects the sampling to record the sampling time and the value, and transmits the moisture content information of the grain to the man-machine interface, so as to realize the detection and dynamic display of the moisture of the grain. The microwave detector 4 measures the propagation loss or frequency characteristics of the microwave in the grain to be detected, and uses the interaction between the microwave and the water molecules to infer the moisture content in the grain. The microwave reflection type nondestructive detection method is adopted, the original state and chemical properties of the grain sample are not damaged in the detection process, the detection method is more economical and faster, and the grain detection sample is saved. The MCU controller 6 is used as the control core, the detection mechanism is simple in design, low in cost, simple and convenient in control process, and can realize real-time detection of the moisture content of the grain in the volume standard mechanism 5.

[0090] Reference Figure 6 , Figure 6The structure schematic view of the distributing mechanism 3 of an embodiment of the present application. The distributing mechanism 3 of the embodiment comprises a roller conveyor 32, a distributing motor 34, side plates 31, a driving sprocket 35 and a driven sprocket 36, the side plates 31 are installed on both sides of the roller conveyor 32, the distributing motor 34 is connected with the controller 6 and the driving sprocket 35 respectively; the driving sprocket 35 is connected with the driven sprocket 36 through a chain 33; the roller conveyor 32 is installed on the side plates 31 and is powered by the chain 33. Wherein, the roller conveyor 32 comprises rollers 321 arranged in sequence and uniformly, the rollers 321 are installed on the side plates 31 through roller shafts 322, the roller shafts 322 are connected with the chain 33, the chain 33 drives the rotation of the roller shafts 322 and the rollers 321. The controller 6 controls the distributing motor 34 to drive the roller conveyor 32 to rotate at a set speed, the rollers 321 are arranged in sequence and uniformly, and the rotating speed is 60-120 r / min; the driving sprocket 35 drives the chain 33 and the driven sprocket 36 to rotate, and the rotating direction is counterclockwise. The chain 33 powers the rollers 321 to rotate; the side plates 31 are fixed on both sides of the roller conveyor 32 by welding, so as to prevent the food from scattering to both sides when falling; the length of the side plates 31 is 300 mm, and the height is 50 mm. The power of the distributing mechanism 3 is derived from the distributing motor 34, and the rotating speed of the distributing motor 34 is controlled by the MCU controller 6; the distributing mechanism 3 is installed in an inclined manner, and the included angle between the distributing mechanism 3 and the horizontal plane is preferably 25°; the vertical distance between the distributing mechanism 3 and the discharge port of the quantitative feeding mechanism 2 is preferably 50 mm, so as to avoid the scattering of the food due to the impact during falling.

[0091] When the grain sample to be detected is fed into the feeding bin 21 in the feeding mechanism, the photoelectric probe 28 installed in the feeding bin 21 detects the height of the grain plane to the bottom of the feeding bin, and when the grain height reaches the set height, the feeding into the feeding bin 21 is stopped; then the distributing mechanism 3 is started, the roller 25 rotates to drive the grain to fall to the roller distributor, and then the roller distributor can uniformly feed the grain into the volume standard mechanism 5 on the horizontal conveying belt 51; when the grain completely falls into the volume standard mechanism 5, the telescopic cylinder 56 is started to drive the scraping plate 55 to level the surface of the grain, so that the grain uniformly fills the volume standard mechanism 5, and the thickness of the grain at each position is consistent, which can effectively avoid the influence of the different thicknesses of the grain on the accuracy of the detection result, and meanwhile, the device manufacturing cost is reduced on the basis of realizing the online detection of the grain moisture. The horizontal conveying belt 51 runs at a speed of 10-20 mm / s, and the microwave moisture detector above the horizontal conveying belt 51 is used to detect the moisture content of the grain in the volume standard mechanism 5. In this process, the microwave emission probe 43 emits a microwave signal, which sends the microwave signal into the grain to be detected, and the microwave receiving probe 44 receives the microwave signal reflected by the material. The sensitivity and accuracy of the microwave receiving probe 44 have a great influence on the measurement result. Then the grain moisture information is transmitted to the controller 6, and the moisture value can be displayed on the human-computer interaction interface; finally, the controller 6 sends an action signal to the proximity switch 73 to open the unloading port of the volume standard mechanism 5, so that the grain enters the receiving hopper 72, and the detection of the grain moisture by the microwave moisture detection device is completed.

[0092] The application also provides an online grain moisture detection method, which comprises the following steps:

[0093] In step S100, the grain sample to be detected is fed into the feeding bin 21, and the photoelectric probe 28 detects the height value H of the upper surface of the grain sample to be detected to the bottom of the feeding bin 21; when the height value H reaches the set height, the feeding into the feeding bin 21 is stopped.

[0094] In step S200, the distributing mechanism 3 is started, the roller 25 rotates to drive the grain sample to fall to the roller distributor, and the roller distributor uniformly feeds the grain sample into the volume standard mechanism 5 on the horizontal conveying belt 51.

[0095] In step S300, when the grain sample to be detected completely falls into the volume standard mechanism 5, the electric telescopic scraper is started to level the surface of the grain sample, so that the grain sample uniformly fills the volume standard mechanism 5, and the thickness of the grain sample at each position is consistent.

[0096] Step S400, the microwave moisture detector detects the water content of the grain sample to be detected in the volume standard mechanism 5, and calculates the moisture content of the grain sample to be detected to obtain the grain water content;

[0097] Step S500, the grain water content information is transmitted to the controller 6 and displayed on the human-computer interaction interface; and

[0098] Step S600, the controller 6 controls to open the unloading port of the volume standard mechanism 5, and sends the detected grain sample to be detected into the receiving hopper 72, and completes the detection of the grain water content.

[0099] The application has good stability, high accuracy and good repeatability for rapid real-time online grain moisture detection in the grain drying process.

[0100] Of course, the application can have other various embodiments, and those skilled in the art can make various corresponding changes and modifications according to the application without departing from the spirit and essence of the application. However, these corresponding changes and modifications should belong to the protection scope of the claims attached to the application.

Claims

1. An online grain moisture detection device, characterized in that, The utility model relates to a kind of microwave detection device for grain moisture content, including: Rack; Volume standard mechanism, mounted on the rack, including horizontal conveying belt, baffle, step motor and multiple partitions, the step motor is connected with the horizontal conveying belt, and the horizontal conveying belt is driven to move;The baffle is located on both sides of the horizontal conveying belt;Multiple partitions are all arranged on the horizontal conveying belt, and are enclosed into closed cavity with the baffle respectively; Microwave detector, installed above the volume standard mechanism; Quantitative feeding mechanism, connected with the volume standard mechanism through distributing mechanism, and the distributing mechanism is obliquely arranged; And Controller, respectively connected with quantitative feeding mechanism, distributing mechanism, step motor and microwave detector; Wherein, the microwave detector includes installation top plate, microwave emission probe, microwave receiving probe, bottom plate and fixed plate, the installation top plate is connected with the rack;The fixed plate is symmetrically arranged on both sides of the installation top plate and is connected with the installation top plate and bottom plate respectively;Microwave emission probe and microwave receiving probe are installed on the corresponding fixed plate;Microwave port is provided on the bottom plate corresponding to the microwave emission probe and microwave receiving probe; The quantitative feeding mechanism includes feed bin, photoelectric probe, feeding motor, rolling screw, vertical slide rail and sliding block;The feed bin is installed on the rack;The rolling screw is connected with the feeding motor, and the feeding motor is installed above the feed bin through horizontal support beam and drives the rolling screw to rotate; The vertical slide rail is arranged in parallel with the rolling screw, and the sliding block is installed on the rolling screw and connected with the vertical slide rail;The rolling screw rotates while driving the sliding block to move up and down along the vertical slide rail;Photoelectric probe is installed on the side of the sliding block and is connected with the controller;The photoelectric probe horizontally emits detection line, and transmits feedback signal to the controller; The volume standard mechanism is also provided with telescopic screed, located below the distributing mechanism, and the telescopic screed includes telescopic cylinder and screed plate, one end of the telescopic cylinder is installed on the rack, and the other end of the telescopic cylinder is connected with the screed plate.

2. The online grain moisture detection device of claim 1, wherein It also includes unloading mechanism, including receiving hopper and proximity switch, the receiving hopper is installed on the rack and is arranged corresponding to the grain outlet of the volume standard mechanism;The proximity switch is installed in the quantitative feeding mechanism close to the grain outlet and is connected with the controller.

3. The online grain moisture detection device of claim 1, wherein The installation bottom surface of the microwave emission probe and the microwave receiving probe is attached to the fixed plate;The horn mouth of the microwave emission probe and the microwave receiving probe is inward, and the included angle between the central axis of the microwave emission probe and the horizontal plane is 53 °, and the included angle between the central axis of the microwave receiving probe and the horizontal plane is-53 °.

4. The on-line grain moisture detection apparatus as claimed in claim 1 or 3, wherein The microwave port is rectangular, and the microwave emitted by the microwave emission probe reaches the surface of the grain sample to be detected through the microwave port, and the microwave receiving probe receives the microwave reflected by the surface of the grain sample to be detected through the microwave port.

5. The online grain moisture detection device of claim 1, wherein The bottom of the feeding bin is provided with a pushing motor, a roller and a plurality of discharge blades corresponding to the distributing mechanism, the roller shaft is fittedly installed with the both sides shaft holes of the bottom of the feeding bin, one end of the roller shaft is connected with the pushing motor, and the pushing motor is connected with the controller; the discharge blades are evenly distributed on the roller shaft.

6. The online grain moisture detection apparatus of claim 1, wherein The distributing mechanism comprises a roller conveyor, a distributing motor, side plates, a driving sprocket and a driven sprocket, the side plates are installed on the both sides of the roller conveyor, the distributing motor is connected with the controller and the driving sprocket respectively, the driving sprocket is connected with the driven sprocket through a chain, and the roller conveyor is installed on the side plates and is driven by the chain.

7. The online grain moisture detection apparatus as claimed in claim 6, wherein The roller conveyor comprises rollers arranged in sequence and evenly, the rollers are installed on the side plates through roller shafts, the roller shafts are connected with the chain, and the chain drives the rotation of the roller shafts and the rollers.

8. An online grain moisture detection method, characterized in that, The online grain moisture detection device comprises the following steps: S100, feeding a grain sample to be detected into a feeding bin, and detecting the height value H from the upper surface of the grain sample to be detected to the bottom of the feeding bin by a photoelectric probe; when the height value H reaches a set height value, stop feeding the grain sample to the feeding bin; S200, starting a distributing mechanism, rotating a roller to drive the grain sample to be detected to fall to a roller distributor, and evenly feeding the grain sample to be detected into a volume standard mechanism on a horizontal conveyor belt by the roller distributor; S300, when the grain sample to be detected completely falls into the volume standard mechanism, starting an electric telescopic screed to level the surface of the grain sample to be detected, so that the grain sample to be detected uniformly fills the volume standard mechanism and ensures the thickness consistency of the grain sample to be detected at different positions; S400, detecting the moisture content of the grain sample to be detected in the volume standard mechanism by a microwave moisture detector, and calculating the moisture content of the grain sample to be detected to obtain the grain moisture content; S500, transmitting the grain moisture content information to a controller, and displaying the information on a man-machine interactive interface; and S600, the controller controls to open a grain discharge port of the volume standard mechanism, feeds the grain sample to be detected after detection into a receiving hopper, and completes the detection of the grain moisture content.

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