Automatic microwave drying control method and control system for sand mould material
The automatic microwave drying control system has achieved full automation and intelligence in the 3D printing sand casting process, solving the problems of high energy consumption, long time and low automation of traditional natural gas drying, improving production efficiency and product quality, and reducing energy consumption.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-08
- Publication Date
- 2026-03-10
AI Technical Summary
Traditional natural gas drying methods in 3D printing sand casting are energy-intensive, time-consuming, have low automation, require a lot of manual intervention, and are difficult to adapt to changes in materials.
An automatic microwave drying control method is adopted, which uses a PLC controller combined with weighing and position sensors to achieve fully automated control of the entire process. It automatically identifies the weight of the material and matches the microwave drying power and time. Combined with the microwave generating mechanism and sealing system, it realizes fully automated and intelligent drying.
It significantly improves production efficiency, reduces energy consumption, shortens drying time, ensures product quality, reduces manual intervention, and adapts to changes in materials from different batches.
Smart Images
Figure CN121624359A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of microwave heating technology, and more specifically to the field of an automatic microwave drying control method and control system for sand mold materials. Background Technology
[0002] In the 3D printing sand casting industry, drying and solidifying the sand mold material is a crucial step in the production process. Traditional drying methods, which use natural gas-heated drying chambers, have the following problems: 1. Natural gas drying has high energy consumption, requiring approximately 40 kWh of electricity per ton of material to dry, and the drying time for each batch of material is long, approximately 24 hours per ton.
[0003] 2. High labor costs: manual intervention is required to modify process parameters to ensure uniform drying.
[0004] 3. Low level of automation, making it difficult to identify process parameters after changes in the combination of drying materials. Summary of the Invention
[0005] The purpose of this invention is to provide an automatic microwave drying control method and control system for sand mold materials in order to solve the above-mentioned technical problems.
[0006] To achieve the above objectives, the present invention specifically adopts the following technical solution: One aspect of the present invention provides an automatic microwave drying control method for sand mold materials, comprising the following steps: S1. Sand mold materials are hoisted or automatically grabbed by a robotic arm and placed onto the material tray on the feed roller conveyor; S2. The position sensor on the feed roller conveyor opens the weighing sensor component after it detects that there is material on the loading tray. S3. The weighing sensor component of the feed roller conveyor automatically reads the weight of the sand mold material and transmits the data to the PLC controller. S4, PLC controller automatically identifies the power required for microwave drying and drying time based on the data from the weighing sensor component; S5. Drive the opening of the feed chamber door assembly of the drying chamber, and the feed roller conveyor and the inner roller conveyor move the material tray to the drying position; S6. Close the feed chamber door assembly, and press the feed chamber door assembly and discharge chamber door assembly of the drying chamber to achieve microwave sealing of the drying chamber; The S7 and PLC controllers control the output power of the microwave power supply and activate water cooling, ventilation, and rotating antenna to begin automatic drying. S8. Drying is complete. Open the discharge chamber door assembly. S9. The internal roller conveyor and the discharge roller conveyor operate simultaneously, sending the material tray onto the discharge roller conveyor. S10. The material is transported away by hoisting the sand-shaped material onto the pallet or by an automated transfer robot (AGV).
[0007] In one embodiment, in step S2, position sensors are installed at the front, middle and rear positions on the feed roller conveyor. The position sensors identify whether there is material on the material tray on the feed roller conveyor. If it is determined that there is material on the material tray, the weighing sensor component is activated.
[0008] In one embodiment, in step S3, the weighing sensor automatically reads the weight of the sand material and transmits the weight to the PLC controller in real time. After receiving the collected data, the PLC controller automatically calculates the microwave drying power and time required for the weight based on the mapping relationship of the weight.
[0009] In one implementation, in step S3, the PLC controller has a pre-stored "weight-power-time" lookup table. The PLC controller automatically matches and sets the power and drying time for this drying based on the weight of the sand material read.
[0010] In one embodiment, in step S6, after the material tray is in place, the limit sensor sends a feedback signal to the PLC controller, which then controls the closing of the feeding door and drives the sealing cylinder of the feeding door to press the feeding door against the sealing shield, so that the drying chamber forms an electrically sealed chamber to ensure that microwaves cannot leak.
[0011] In one embodiment, in step S7, the PLC controller controls the microwave power supply to turn on and outputs the corresponding power as needed; at the same time, the water cooling system, the ventilation system and the antenna rotation system are turned on. The water cooling system is used to cool the microwave generator and the microwave transmission circuit; the ventilation system is used to extract the evaporated water vapor in the cavity; the antenna rotation system makes the microwave field evenly cover the drying cavity and starts automatic drying.
[0012] A second aspect of the present invention provides an automatic microwave drying control system for sand mold materials, applicable to the aforementioned automatic microwave drying control method for sand mold materials, comprising a feeding roller conveyor, a feeding chamber door assembly, a drying chamber, a discharging chamber door assembly, a discharging roller conveyor, and a microwave generating mechanism arranged sequentially; the microwave generating mechanism is located inside the drying chamber. The microwave generating mechanism includes multiple microwave generating units. Each microwave generating unit includes a microwave head, a circulator, a three-pin adjustment component, and a waveguide. The microwave head is connected to the circulator via a magnetron, and the circulator is connected to the waveguide. The waveguide end is connected to a three-pin adjustment component for adjusting the impedance matching between the front and rear ends to improve the microwave absorption efficiency. The magnetron inside the microwave head is preheated and then excited by high voltage to generate microwaves. The circulator absorbs and reflects the microwave power to protect the magnetron. The three-pin adjustment component adjusts the impedance matching of the front and rear ends to improve the microwave absorption efficiency. The waveguide transmits the microwave energy to the drying chamber.
[0013] In one embodiment, the feed chamber door assembly and the discharge chamber door assembly have the same structure. Both the feed chamber door assembly and the discharge chamber door assembly include a door frame, a door slidably disposed on the door frame, and multiple sets of sealing cylinders arranged on the door frame to drive the door to rise and fall. Specifically, when the cavity needs to move up and down, the cylinder retracts; when the cavity descends to the correct position, the cylinder pushes out to press the cavity tightly to achieve a seal.
[0014] In one embodiment, the feed roller conveyor and the discharge roller conveyor have the same structure. The feed roller conveyor includes a roller conveyor body, a weighing sensing component, a material tray, and a position sensor. The material tray is located above the roller conveyor body and is used to carry materials. The roller conveyor body is provided with a transmission mechanism to realize the material tray transfer function. The weighing sensing component includes multiple sets of weighing sensors located below the roller conveyor body to realize the weighing of materials. The position sensor is located on the side of the roller conveyor body near the feed chamber door and is used to identify the position of the material tray and determine whether there is material.
[0015] In one embodiment, the drying chamber includes a cavity, an inner roller conveyor disposed within the cavity, an exhaust fan disposed at the top of the cavity, cooling water channels wound around the outer wall of the cavity, and a rotating antenna disposed at the top of the cavity. The rotating antenna agitates microwaves to make the microwaves radiate evenly within the cavity. The two ends of the inner roller conveyor are respectively engaged with the feed roller conveyor and the discharge roller conveyor. The front and rear sides of the cavity are respectively provided with mounting holes for mounting the feed chamber door assembly and the discharge chamber door assembly.
[0016] Specifically, the two ends of the inner roller conveyor are respectively connected to the feed roller conveyor and the discharge roller conveyor to realize the material tray entering and leaving the cavity. The exhaust fan discharges the water vapor generated during the drying process in the cavity. The cooling water circuit connects the cooling structures of each part to provide cooling water for the system. The rotating antenna stirs the microwave to make the microwave radiation uniform in the cavity.
[0017] The beneficial effects of this invention are as follows: 1. This invention automates the entire process, achieving complete closed-loop automated control from material identification, weight detection, process matching, pallet transfer, microwave sealing, microwave drying, and discharge, significantly reducing the need for manual intervention and improving production efficiency.
[0018] 2. Intelligent drying: The system can automatically identify the required microwave power and running time of the material by weight, so that the drying process can be adapted to the actual conditions of multiple batches of different materials, avoiding under-drying and over-drying problems caused by material changes, and ensuring product quality.
[0019] 3. Reduced energy consumption: After using the microwave drying system, the energy consumption has been reduced from 40 kWh per ton to 6 kWh, and the drying time has been shortened from 24 hours per ton to 1 hour per ton. Attached Figure Description
[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.
[0021] Figure 1 This is a flowchart of an automatic microwave drying control method for sand mold materials according to the present invention.
[0022] Figure 2 This is a front view of an automatic microwave drying control system for sand-shaped materials; Figure 3 yes Figure 2 Side view; Figure 4 This is a schematic diagram of the microwave generator mechanism; Reference numerals: 1. Feed roller conveyor; 2. Discharge roller conveyor; 3. Feed chamber door assembly; 4. Discharge chamber door assembly; 5. Microwave generating mechanism; 6. Drying chamber; 101. Roller conveyor body; 102. Material tray; 103. Weighing sensor assembly; 104. Position sensor; 301. Chamber door; 302. Sealing cylinder; 501. Microwave head; 502. Circulator; 503. Three-pin adjustment component; 504. Waveguide; 601. Inner roller conveyor; 602. Exhaust fan; 603. Cooling water channel; 604. Rotating antenna. Detailed Implementation
[0023] To make the technical problems, technical solutions, and technical effects of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0024] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.
[0025] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0026] In the description of the embodiments of the present invention, it should be noted that the terms "inner", "outer", "upper", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.
[0027] This invention provides an automatic microwave drying control method for sand mold materials, comprising the following steps: S1. Sand mold materials are hoisted or automatically grabbed by a robotic arm and placed onto the material loading tray 102 on the feed roller conveyor 1; S2. After the position sensor 104 on the feed roller conveyor 1 detects that there is material on the material tray 102, the weighing sensor component 103 is opened. S3, The weighing sensor component 103 of the feed roller conveyor 1 automatically reads the weight of the sand mold material and transmits the data to the PLC controller; S4, the PLC controller automatically identifies the power required for microwave drying and the drying time based on the data from the weighing sensor component 103; S5. Drive the opening of the feed chamber door assembly 3 of the drying chamber 6, and the feed roller conveyor 1 and the inner roller conveyor 601 move the material tray 102 to the drying position. S6. Close the feed chamber door assembly 3, and press the feed chamber door assembly 3 and the discharge chamber door assembly 4 of the drying chamber 6 together to achieve microwave sealing of the drying chamber; The S7 and PLC controllers control the output power of the microwave power supply and activate the water cooling, ventilation, and rotating antenna 604 to start automatic drying. S8. Drying is complete. Open the discharge chamber door assembly 4. S9. The internal roller conveyor 601 and the discharge roller conveyor 2 operate simultaneously, sending the material tray 102 onto the discharge roller conveyor 2. S10, The material is transported by hoisting in sand molds or by being transported by an automated transfer robot (AGV) on the pallet 102.
[0028] Specifically, this solution integrates weighing sensors, position sensors, and frequency converters, and uses a PLC controller to automate the entire process of material transfer, drying, and process parameter adjustment. It can automatically match the optimal drying microwave power and time according to the material weight, thereby improving production efficiency, ensuring drying quality, and reducing energy consumption.
[0029] In one embodiment, in step S2, position sensors 104 are installed at the front, middle and rear positions on the feed roller conveyor 1. The position sensors 104 identify whether there is material on the material tray 102 on the feed roller conveyor 1. If it is determined that there is material on the material tray 102, the weighing sensor component 103 is activated.
[0030] In one embodiment, in step S3, the weighing sensor component 103 automatically reads the weight of the sand mold material and transmits the weight to the PLC controller in real time. After receiving the collected data, the PLC controller automatically calculates the microwave drying power and time required for the weight based on the mapping relationship of the weight.
[0031] In one implementation, in step S3, the PLC controller has a pre-stored "weight-power-time" lookup table. The PLC controller automatically matches and sets the power and drying time for this drying based on the weight of the sand material read.
[0032] In one embodiment, in step S6, after the material tray 102 is in place, the limit sensor sends a feedback signal to the PLC controller, which then controls the closing of the feeding door and drives the infeed / outfeed door sealing cylinder 302 to press the feeding door against the sealing shield, so that the drying chamber 6 forms an electrically sealed chamber to ensure that microwaves cannot leak.
[0033] In one embodiment, in step S7, the PLC controller controls the microwave power supply to turn on and outputs the corresponding power as needed; at the same time, the water cooling system, the ventilation system and the antenna rotation system are turned on. The water cooling system is used to cool the microwave generator and the microwave transmission circuit; the ventilation system is used to extract the evaporated water vapor in the cavity; the antenna rotation system makes the microwave field evenly cover the drying chamber 6 and starts automatic drying.
[0034] Example 1 like Figures 2 to 4 As shown, this embodiment provides an automatic microwave drying control system for sand mold materials, which is applicable to the above-mentioned automatic microwave drying control method for sand mold materials. It includes a feeding roller conveyor 1, a feeding chamber door assembly 3, a drying chamber 6, a discharging chamber door assembly 4, a discharging roller conveyor 2, and a microwave generating mechanism 5 arranged in sequence; the microwave generating mechanism 5 is located inside the drying chamber 6. The microwave generating mechanism 5 includes multiple microwave generating units. Each microwave generating unit includes a microwave head 501, a circulator 502, a three-pin adjustment component 503, and a waveguide 504. The microwave head 501 is connected to the circulator 502 through a magnetron. The circulator 502 is connected to the waveguide 504. The end of the waveguide 504 is connected to a three-pin adjustment component 503 for adjusting the impedance matching of the front and rear ends to improve the microwave absorption efficiency. After preheating, the magnetron inside the microwave head 501 is excited by high voltage to generate microwaves. The circulator 502 absorbs and reflects microwave power to protect the magnetron. The three-pin adjustment component 503 adjusts the impedance matching of the front and rear ends to improve the microwave absorption efficiency. The waveguide 504 transmits microwave energy to the drying chamber 6.
[0035] In one embodiment, the feed chamber door assembly 3 and the discharge chamber door assembly 4 have the same structure. Both the feed chamber door assembly 3 and the discharge chamber door assembly 4 include a door frame, a door 301 slidably disposed on the door frame, and multiple sets of sealing cylinders 302 arranged on the door frame to drive the door 301 to rise and fall.
[0036] Specifically, when the cavity door 301 needs to move up and down, the cylinder retracts; when the cavity door 301 descends to the position, the cylinder pushes out to press the cavity door tightly to achieve a seal.
[0037] In one embodiment, the feed roller conveyor 1 and the discharge roller conveyor 2 have the same structure. The feed roller conveyor 1 includes a roller conveyor body 101, a weighing sensor component 103, a material carrier tray 102, and a position sensor 104. The material carrier tray 102 is located above the roller conveyor body 101 and is used to carry materials. The roller conveyor body 101 is provided with a transmission mechanism to realize the transfer function of the material carrier tray 102. The weighing sensor component 103 includes multiple sets of weighing sensors located below the roller conveyor body 101 to realize the weighing of materials. The position sensor 104 is located on the side of the roller conveyor body 101 near the feed chamber door and is used to identify the position of the material carrier tray 102 and determine whether there is material.
[0038] In one embodiment, the drying chamber 6 includes a cavity, an inner roller conveyor 601 disposed within the cavity, an exhaust fan 602 disposed at the top of the cavity, a cooling water channel 603 wound around the outer wall of the cavity, and a rotating antenna 604 disposed at the top of the cavity. The rotating antenna 604 agitates the microwaves to make the microwaves radiate evenly within the cavity. The two ends of the inner roller conveyor 601 are respectively engaged with the feed roller conveyor 1 and the discharge roller conveyor 2. The front and rear sides of the cavity are respectively provided with mounting holes for installation with the feed chamber door assembly 3 and the discharge chamber door assembly 4.
[0039] Specifically, the two ends of the inner roller conveyor 601 are respectively connected to the feed roller conveyor 1 and the discharge roller conveyor 2 to realize the material tray 102 entering and exiting the cavity. The exhaust fan 602 discharges the water vapor generated in the drying process in the cavity. The cooling water circuit 603 connects the cooling structures of each part to provide cooling water for the system. The rotating antenna 604 stirs the microwave to make the microwave radiation uniform in the cavity.
[0040] Example 2 like Figure 1 As shown, this embodiment provides an automatic microwave drying control method for sand mold materials. In the initial state of the system, all equipment is in standby position, and the operator hoists the material tray 102 carrying the sand mold material onto the feed roller conveyor 1; including the following steps: S1. The material tray 102 runs with the feeding roller 1. When it reaches the detection area of the position sensor 104, the position sensor 104 detects the presence of material on the material tray 102 and sends a signal to the PLC controller. The PLC controller then drives the weighing sensor component 103 to start working, accurately obtains the current material weight (e.g., 1500kg), and stores the data.
[0041] S2. The PLC controller has a pre-stored "weight-power-time" lookup table. Based on the read weight, the PLC controller automatically matches and sets the power for this drying to 100kW and the drying time to 12 minutes.
[0042] "Weight-Power-Time Lookup Table"
[0043] After the S3 parameters are set, the PLC controller drives the cavity door motor to open the feeding door; at the same time, it starts the motors of the feeding roller 1 and the cavity roller 601 to smoothly send the material tray 102 into the designated position in the drying chamber 6; after the material tray 102 is in place, the limit sensor feeds back a signal to the PLC controller, and the PLC controller then controls the closing of the feeding door and drives the inlet / outlet door sealing cylinder 302 to press the inlet / outlet door tightly onto the sealing shielding strip, so that the drying chamber 6 forms an electrically sealed chamber to ensure that microwaves cannot leak.
[0044] The S4 and PLC controllers start sequentially according to a preset program: the water cooling system, the ventilation system, and the antenna rotation system. The water cooling system cools microwave devices such as the magnetron, circulator 502, and water load; the ventilation system removes water vapor generated during the drying process; and the antenna rotation system ensures uniform microwave distribution within the cavity. A drive is then sent to the microwave power supply, enabling it to output microwaves at 100kW to begin a 12-minute automatic drying process.
[0045] After the 18-minute countdown ends, the PLC controller first shuts off the microwave power supply and the antenna rotation system, then controls the inlet / outlet door sealing cylinder 302 to retract and unlock the door; subsequently, it drives the outlet door motor to open the outlet door; finally, it starts the inner roller conveyor 601 and the outlet roller conveyor 2 to send the dried material and the material tray 102 out of the drying chamber 6, completing a full work cycle.
Claims
1. A method for automatically controlling microwave drying of a sand molding material, characterized by, The method comprises the following steps: S1, the sand material is hoisted or automatically grabbed by a manipulator to a load tray (102) on a feeding roller (1); S2, a position sensor (104) on the feeding roller (1) identifies that the load tray (102) has material, and then opens a weighing sensor assembly (103) sensor; S3, the weighing sensor assembly (103) on the feeding roller (1) automatically reads the weight of the sand material and transmits the data to a PLC controller; S4, the PLC controller automatically identifies the required power and drying time of microwave drying according to the data of the weighing sensor assembly (103); S5, a feeding cavity door assembly (3) of a drying cavity (6) is driven to be opened, the feeding roller (1) and an inner cavity roller (601) operate the load tray (102) to a drying position; S6, the feeding cavity door assembly (3) is closed, the feeding cavity door assembly (3) and a discharging cavity door assembly (4) of the drying cavity (6) are tightly closed, and a microwave sealing cavity of the drying cavity is realized; S7, the PLC controller controls the output power of a microwave power supply, and starts water cooling, air extraction and antenna rotation (604) to start automatic drying; S8, when the drying is completed, the discharging cavity door assembly (4) is opened; S9, the inner cavity roller (601) and a discharging roller (2) operate simultaneously to send the load tray (102) to the discharging roller (2); S10, the sand material is hoisted or transferred by an automatic transfer robot AGV to move the load tray (102).
2. The automatic microwave drying control method of a sand mold material according to claim 1, characterized by, In step S2, front, middle and rear position sensors (104) are installed on the feeding roller (1), the position sensors (104) identify whether the load tray (102) on the feeding roller (1) has material, and if the load tray (102) has material, the weighing sensor assembly (103) sensor is enabled.
3. The automatic microwave drying control method of a sand mold material according to claim 1, characterized by, In step S3, the weighing sensor assembly (103) automatically reads the weight of the sand material, and transmits the weight to the PLC controller in real time. After the PLC controller receives the data, the required microwave drying power and time for the weight are automatically calculated based on the mapping relationship of the weight.
4. The automatic microwave drying control method of a sand mold material according to claim 3, characterized by, In step S3, a "weight-power-time" query table is pre-stored in the PLC controller. The PLC controller automatically matches and sets the power and drying time of this drying according to the weight of the sand material.
5. The automatic microwave drying control method of a sand mold material according to claim 1, characterized by, In step S6, after the load tray (102) is positioned, a limit sensor feeds back a signal to the PLC controller, the PLC controller immediately controls the feeding door to be closed, drives the feeding and discharging door sealing cylinder (302) to act, tightly closes the feeding door on the sealing shielding strip, and forms an electric sealing cavity of the drying cavity (6) to ensure that the microwave cannot leak.
6. The automatic microwave drying control method of a sand molding material according to claim 1, characterized by, In step S7, the PLC controller controls the microwave power supply to be started and outputs the corresponding power according to the requirement; simultaneously, a water cooling system, an air extraction system and an antenna rotation system are started, the water cooling system is used for cooling the microwave generator and a microwave transmission loop, the air extraction system is used for extracting evaporated water vapor in the cavity, and the antenna rotation system makes the microwave field uniformly cover the drying cavity (6) to start automatic drying.
7. A sand mold material automatic microwave drying control system suitable for a sand mold material automatic microwave drying control method according to any one of claims 1 to 6, characterized by, It comprises feeding roller (1), feeding cavity door assembly (3), drying chamber (6), discharging cavity door assembly (4), discharging roller (2) and microwave generating mechanism (5) arranged in sequence; the microwave generating mechanism (5) is located in the drying chamber (6); The microwave generating mechanism (5) comprises multiple groups of microwave generating units, each of which comprises a microwave head (501), a circulator (502), a three-pin adjusting piece (503) and a waveguide (504), the microwave head (501) is connected with the circulator (502) through a magnetron, the circulator (502) is communicated with the waveguide (504), and the waveguide (504) is connected with the three-pin adjusting piece (503) at the end for adjusting the impedance matching of the front and rear ends to improve the microwave absorption efficiency. The magnetron in the microwave head (501) generates microwaves after preheating and high-voltage excitation, the circulator (502) absorbs reflected microwave power to protect the magnetron, the three-pin adjusting piece (503) adjusts the impedance matching of the front and rear ends to improve the microwave absorption efficiency, and the waveguide (504) transmits microwave energy into the drying chamber (6).
8. The automatic microwave drying control system for sand moulding material according to claim 7, characterized in that, The feeding cavity door assembly (3) and the discharging cavity door assembly (4) are the same structure, the feeding cavity door assembly (3) and the discharging cavity door assembly (4) both comprise a door frame, a cavity door (301) slidingly arranged on the door frame and multiple groups of sealing cylinders (302) arranged on the door frame to drive the cavity door (301) to lift.
9. The automatic microwave drying control system for sand molding material according to claim 7, wherein The feeding roller (1) and the discharging roller (2) are the same structure, the feeding roller (1) comprises a roller main body (101), a weighing sensor assembly (103), a material carrying tray (102) and a position sensor (104); the material carrying tray (102) is located above the roller main body (101) for carrying materials, a transmission mechanism for realizing the transfer function of the material carrying tray (102) is arranged on the roller main body (101); the weighing sensor assembly (103) comprises multiple groups of weighing sensors located below the roller main body (101) to realize material weighing, and the position sensor (104) is arranged on the roller main body (101) close to the feeding cavity door side to identify the position of the material carrying tray (102) and determine whether there is material.
10. The automatic microwave drying control system for sand molding material according to claim 7, wherein The drying chamber (6) comprises a cavity, a cavity-in roller (601) arranged in the cavity, an exhaust fan (602) arranged on the top of the cavity, a cooling waterway (603) wound on the outer wall of the cavity and a rotating antenna (604) arranged on the top of the cavity, the rotating antenna (604) stirs microwaves to make the microwaves radiate uniformly in the cavity, the two ends of the cavity-in roller (601) are respectively matched with the feeding roller (1) and the discharging roller (2), and the front and rear sides of the cavity are respectively provided with mounting door holes for mounting the feeding cavity door assembly (3) and the discharging cavity door assembly (4).