CN106820206B

CN106820206B - Rotary drum type microwave drying equipment

Info

Publication number: CN106820206B
Application number: CN201710213599.0A
Authority: CN
Inventors: 铃木隆之
Original assignee: Jiangsu Jinghe Automation Engineering Co ltd
Current assignee: Jiangsu Jinghe Automation Engineering Co ltd
Priority date: 2017-04-01
Filing date: 2017-04-01
Publication date: 2023-07-18
Anticipated expiration: 2037-04-01
Also published as: CN106820206A

Abstract

The invention relates to rotary drum type microwave drying equipment, which comprises a frame, wherein a rotary heating drum which is transversely arranged is arranged in the frame, one end of the rotary heating drum is provided with a cover plate, and the other end of the rotary heating drum is sequentially connected with a regulator, a waveguide tube and a microwave generator; an electric cabinet is arranged at the top of the frame, a fan is arranged at the lower part of the frame, and the fan is connected with the rotary heating roller through a pipeline. The invention has compact and reasonable structure and convenient operation, has stronger drying capacity and excellent drying quality by adopting the roller type structure, and uniformly stirs, heats and dries by the roller; the processing is convenient, and the operation is directly carried out on the window; the problem of electric wave leakage in the prior art is avoided, and the electric wave can be dried in a closed state, so that zero leakage can be almost achieved.

Description

Rotary drum type microwave drying equipment

Technical Field

The invention relates to the technical field of microwave drying devices, in particular to rotary drum type microwave drying equipment.

Background

The microwave drying is different from the traditional drying mode, and the heat conduction direction is the same as the water diffusion direction. Compared with the traditional drying mode, the method has the advantages of high drying rate, energy conservation, high production efficiency, uniform drying, clean production, easy realization of automatic control, improvement of product quality and the like, and therefore, the method is more and more important in various fields of drying. Extensive research into the application and theory of microwave drying technology has been carried out abroad as early as 60 s of the last century, and further development has been made in the last decades.

The microwave drying equipment in the prior art generally adopts a conveyor belt type structure, has a simple structure and strong drying capacity, but has the following defects:

(1) The dried product has poor quality, may have spots, and may be left with scorch, and a stirrer or the like may be used, but its function is limited.

(2) The processing capacity is poor, and the continuous processing can realize wireless ore size.

(3) The operability is poor, the loading and unloading are easy, the automation can be realized, but the management is not good.

(4) The radio wave leakage, the security performance is poor, the radio wave leakage of the opening part needs to be solved, and the leakage is reduced through the choke coil and the radio wave absorber.

Disclosure of Invention

The applicant provides a rotary drum type microwave drying apparatus of reasonable structure, which aims at the defects in the prior art.

The technical scheme adopted by the invention is as follows:

the rotary drum type microwave drying equipment comprises a frame, wherein a rotary heating drum which is transversely arranged is arranged in the frame, a cover plate is arranged at one end of the rotary heating drum, and the other end of the rotary heating drum is sequentially connected with a regulator, a waveguide tube and a microwave generator; an electric cabinet is arranged at the top of the frame, a fan is arranged at the lower part of the frame, and the fan is connected with the rotary heating roller through a pipeline.

As a further improvement of the above technical scheme:

the installation structure in the rotary heating roller is as follows: the novel high-speed hydraulic pump comprises a main shaft, wherein the main shaft is of a hollow structure, the outer circumferential surface of the main shaft is provided with a bearing seat through a bearing, the bearing seat is connected with a fixed plate through a fastener, the fixed plate is also provided with a teflon plate, and the outer circumferential surface of the bearing seat is also provided with a driving gear; the end face of the main shaft is provided with a positioning plate through a locking piece.

An electric heater is also arranged on the rotary heating roller.

The cover plate is connected with the rotary heating roller through a hinge, a plurality of mounting holes are formed in the cover plate, and the cover plate is locked with the rotary heating roller through a fastener when the cover plate is closed.

The waveguide tube is made of aluminum or stainless steel.

The beneficial effects of the invention are as follows:

the invention has compact and reasonable structure and convenient operation, has stronger drying capacity and excellent drying quality by adopting the roller type structure, and uniformly stirs, heats and dries by the roller; the processing is convenient, and the operation is directly carried out on the window; the problem of electric wave leakage in the prior art is avoided, and the electric wave can be dried in a closed state, so that zero leakage can be almost achieved.

Drawings

Fig. 1 is a front view of the present invention.

Fig. 2 is a top view of fig. 1.

Fig. 3 is a side view of fig. 1.

Fig. 4 is a full cross-sectional view taken along section A-A in fig. 2.

Wherein: 1. an electric control box; 2. a cover plate; 3. a rotary heating drum; 4. a frame; 5. a blower; 6. a regulator; 7. a waveguide; 8. a microwave generator; 9. a fixing plate; 10. a bearing seat; 11. a main shaft; 12. a teflon plate; 13. a bearing; 14. a positioning plate; 16. an electric heater.

Detailed Description

The following describes specific embodiments of the present invention with reference to the drawings.

As shown in fig. 1, 2, 3 and 4, the rotary drum type microwave drying device of the embodiment comprises a frame 4, wherein a rotary heating drum 3 which is transversely arranged is arranged in the frame 4, one end of the rotary heating drum 3 is provided with a cover plate 2, and the other end of the rotary heating drum 3 is sequentially connected with a regulator 6, a waveguide 7 and a microwave generator 8; an electric cabinet 1 is arranged at the top of a frame 4, a fan 5 is arranged at the lower part of the frame 4, and the fan 5 is connected with a rotary heating roller 3 through a pipeline.

The installation structure inside the rotary heating drum 3 is as follows: the device comprises a main shaft 11, wherein the main shaft 11 is in a hollow structure, the outer circumferential surface of the main shaft 11 is provided with a bearing seat 10 through a bearing 13, the bearing seat 10 is connected with a fixed plate 9 through a fastener, the fixed plate 9 is also provided with a teflon plate 12, and the outer circumferential surface of the bearing seat 10 is also provided with a driving gear; the end face of the main shaft 11 is provided with a positioning plate 14 by a locking member.

An electric heater 16 is also mounted on the rotary heating drum 3.

The cover plate 2 is connected with the rotary heating roller 3 through a hinge, a plurality of mounting holes are formed in the cover plate 2, and the cover plate is locked with the rotary heating roller 3 through a fastener when closed.

The waveguide 7 is made of aluminum or stainless steel.

The feeding and discharging of the drying object of the invention are basically manual operation, and the depth of the cylinder body is about 600 mm.

The invention aims at the easy-to-dry articles, can realize continuous treatment by the design of a mechanism and can also carry out feeding and taking materials when microwave vibration occurs, but is limited to the use in the articles with high price and high added value when a large amount of articles are treated.

The microwave generator 8 of the invention generates 2450MHz electromagnetic waves.

The microwave generating device varies depending on the state and final form of the heating object, but generally has a volume of 25L, and the required microwave is 1-2Kw. For good drying, it is desirable to use a relatively low microwave output, supplemented by 70 degrees hot air. Both plants and animals will cause cell destruction after 65 degrees, so the microwave output cannot be too high, or can be intermittently switched to ensure that the temperature is within a suitable range.

The invention is also provided with a leakage prevention device.

The leakage preventing means is the most important mechanism for preventing microwaves irradiated into the drum from leaking to the outside through the rotating portion. If the mechanism cannot exert the proper function, a large amount of electromagnetic waves leak, and serious damage such as damage caused by electric spark at the rotating shaft part can occur. Thus requiring a lot of experience and knowledge for design and manufacturing. The limit of electromagnetic leakage power of microwave ovens in japan is 5mw/cm2 (Max), and this limit value must be clear.

The rotary heating roller 3 is provided with a rotary heating device.

The largest feature of the rotary drum is that water droplets adhering to the objects can be efficiently discharged. On the conveyor belt, the object-to-object relationship is relatively fixed, and it is difficult to remove the water drops trapped between them. The drum type is used, articles are changed from time to time, and the interrelation is changed, so that the water drops mixed with the drum type are easily gasified and discharged. (after washing hands, the same principle as that of washing hands is adopted), if the size of the object to be heated is below that of soybean, the drum can be made of iron plates without using porous plates, and hot air is fed through an iron net on the front face, and exhaust air is discharged for drying. When the object is large, the drum may be made of a perforated plate, and hot air may be fed from the front or the lower side. Various designs are conceivable depending on the object to be heated and dried (refer to fig. 2. If the construction is designed to be quite complicated, the material can be put in and taken out even while the microwave is irradiated. Inside the drum, the object to be dried is agitated by the blades and then falls down, so that it is not suitable for the easily broken article.

The design of the fan 5 adopts hot air circulation.

The microwave itself does not have drying ability, and the microwave can exert drying effect by being used together with hot air. Microwaves act as one of the energy of the electric wave, and are good at heating the inside of the article, and act to squeeze out the moisture inside. The extruded moisture was absorbed and discharged by hot air of 70 degrees to accelerate drying. The cells of plants and animals start to be destroyed after reaching 65 degrees, so the temperature of the hot air should not be too high.

In the actual working process, the device comprises a first working table and a second working table,

the judgment result is greatly different according to the state of the drying object.

If the food with a lot of water (such as cabbage, cabbage and onion) is heated by strong microwave suddenly, the cell is destroyed, a lot of water is generated, and the food is just like chafing dish and boiled vegetables, and the drying effect can not be achieved.

If the water content is 40% or less, drying can be performed using weak microwaves and hot air. At this time, the water content is increased by weak microwaves, and then the water content is gradually increased, and when the water content is less than 15%, scorching may occur, which requires attention.

Like the washed vegetables, the water is sufficiently removed and then put in, and if the drum is made of a porous plate, the water can be effectively promoted to be discharged.

The design of the drum varies from article to article. Please refer to fig. 2.

(II) Experimental procedure (when the degree of dryness is unknown in the early stage)

(a) The dried object (article) was taken 2Kg and measured in this manner, and the mass and temperature were recorded.

(b) The microwave output is set to be 1KW, the temperature of hot air is set to be 70 ℃, the drying object is put into the drum after the temperature of the drum reaches 50 ℃, and the drum is started to rotate and then microwave irradiation is carried out. If the articles are directly put into the drum without preheating, although microwave heating can be performed, the generated water vapor can be cooled on the inner wall of the drum, and the water is condensed again to become water, so that the efficiency is affected.

(c) After heating for about five minutes, the microwave irradiation was stopped, the drum was stopped to rotate, the door was opened, the temperature of the article was measured, and the time and temperature at this time were recorded.

(d) And repeating the steps, judging the drying degree through the hand feeling, and finishing the drying.

(e) After the article was taken out, the mass was measured again, and the amount of water to be discharged was calculated.

(III) the above procedure is repeated by changing the microwave output and the temperature of the hot air to find out the optimal conditions.

(IV) when the water content is reduced by less than 10%, the microwave output can be reduced or intermittently started, so as to prevent the burning and the specking of the articles. Drying with hot air alone does not cause scorching, spots, etc., and can reduce the water content, but takes a long time. Or alternatively, the product can be removed after reaching 10% and placed in a silica gel sealed container to achieve the lowest water content.

The rotary drum type drying equipment is designed and dried under different conditions (microwave output, hot air temperature, air volume) according to different drying objects, preferably a prototype is manufactured, and the design and the manufacture are performed after the judgment is performed through experiments.

And (six) after the drying operation is finished, the drying device is taken out when the temperature is high, dew condensation exists when the drying device contacts with external air, and the moisture is increased. To avoid this, after the drying is completed, the microwave and the electric heater 16 are turned off, but the drum is kept rotating and the air is blown until the temperature is slowly lowered and then taken out, so that there is no fear that the moisture becomes larger again.

The above description is intended to illustrate the invention and not to limit it, the scope of which is defined by the claims, and any modifications can be made within the scope of the invention.

Claims

1. A rotary drum type microwave drying device, characterized in that: the microwave oven comprises a frame (4), wherein a rotary heating roller (3) which is transversely arranged is arranged in the frame (4), a cover plate (2) is arranged at one end of the rotary heating roller (3), and the other end of the rotary heating roller (3) is sequentially connected with a regulator (6), a waveguide tube (7) and a microwave generator (8); an electric cabinet (1) is arranged at the top of the frame (4), a fan (5) is arranged at the lower part of the frame (4), and the fan (5) is connected with the rotary heating roller (3) through a pipeline;

the installation structure inside the rotary heating roller (3) is as follows: the novel high-speed rotating device comprises a main shaft (11), wherein the main shaft (11) is of a hollow structure, a bearing seat (10) is arranged on the outer circumferential surface of the main shaft (11) through a bearing (13), the bearing seat (10) is connected with a fixed plate (9) through a fastener, a teflon plate (12) is further arranged on the fixed plate (9), and a driving gear is further arranged on the outer circumferential surface of the bearing seat (10); the end face of the main shaft (11) is provided with a positioning plate (14) through a locking piece;

an electric heater (16) is also arranged on the rotary heating roller (3); when the rotary drum type microwave drying equipment is used for drying the articles, the method comprises the following steps:

s1, taking an article for metering, and recording the quality and the temperature of the article;

s2, after the rotary heating roller (3) is started to rotate, carrying out microwave irradiation on the article according to the set microwave output, and blowing the article according to the set hot air temperature;

s3, stopping microwave irradiation after heating for five minutes, opening the cover plate (2) after stopping rotating the rotary heating roller (3), measuring the temperature of the article, and recording the time and the temperature at the moment;

s4, repeating the step S3 until the object meets the drying requirement, and ending the drying;

s5, after the articles are taken out, measuring the quality again, and calculating the water content discharged;

s6, after the drying is finished, turning off the microwave generator (8) and the electric heater (16), keeping the rotary heating roller (3) to rotate, and blowing the air until the temperature is slowly reduced, and then taking out the articles;

in step S2, the set values of the microwave output and the hot air temperature are changed according to the type of the article;

in step S3, when the water content is reduced by 10% or less, the output power of the microwave generator (8) may be reduced, or the microwave generator (8) may be intermittently turned on.

2. The rotary-drum microwave drying apparatus of claim 1, wherein: the cover plate (2) is connected with the rotary heating roller (3) through a hinge, a plurality of mounting holes are formed in the cover plate (2), and the cover plate is locked with the rotary heating roller (3) through a fastener when the cover plate is closed.

3. The rotary-drum microwave drying apparatus of claim 1, wherein: the waveguide tube (7) is made of aluminum or stainless steel.