CN112517841B - A kind of microwave heating resin sand core forming device and method thereof - Google Patents

Abstract

The invention discloses a microwave heating resin sand core forming device and a method thereof. The outer frame and the sand inlet hole are characterized in that: the inner wall of the outer frame of the fixed mold and the inner wall of the outer frame of the movable mold are respectively provided with mold blocks which form a cavity between each other; the inner wall of the outer frame of the stationary mold The lower end and the lower end of the inner wall of the outer frame of the movable mold are respectively provided with bottom movable blocks which form a flat bottom surface between each other; the material of the movable mold block and the bottom movable block is ceramics; the lower part of the outer frame of the fixed mold and the outer frame of the movable mold A plurality of microwave dispersing devices are provided; the microwave dispersing device includes a microwave dispersing port located under the bottom movable block, a microwave agitator is arranged in the microwave dispersing port, and the microwave agitator is connected with a motor through a coupling; The lower end is connected with a microwave transmission tube, and the end of the microwave transmission tube is provided with a microwave generator.

Description

A kind of microwave heating resin sand core forming device and method thereof

technical field

The invention relates to the technical field of mould equipment, in particular to a microwave heating resin sand core forming device and a method thereof.

Background technique

Thermoforming resin sand is one of the fastest growing casting processes in the past ten years. The castings produced by thermoforming resin sand have precise dimensions, smooth surfaces, clear edges and corners, low rejection rate, and can save modeling time and improve production. Efficiency, improvement of working conditions and production environment; thermoforming resin sand takes a certain amount of time to heat cure. After molding the core, it is necessary to wait for the resin sand to harden and establish a certain strength before starting the mold. It is difficult to mold. As a core box, due to the thick sand layer, the usual mold-releasing time ranges from 3 minutes to 10 minutes after molding. In addition to the mechanical action time, the efficiency per hour can only be 5-20 cases/hour; this This seriously affects the turnover rate and production efficiency of the mold; and because the hot core box shoots the core and the exhaust channel design is not handled well, the exhaust channel is blocked due to premature curing, resulting in poor exhaust and core shooting failure.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a microwave heating resin sand core forming device and method thereof. The invention can quickly and uniformly heat and solidify the resin sand, reduce the problem that the partial resin sand is prematurely solidified due to uneven heating and block the exhaust passage, and greatly improves the turnover rate and production efficiency of the device.

The technical scheme of the present invention: a microwave heating resin sand core forming device, comprising a fixed mold outer frame, a fixed mold top plate spring, a fixed mold ejector pin, a fixed mold top plate, a movable mold ejector pin, a movable mold ejector pin plate, a movable mold ejector The inner wall of the outer frame of the fixed mold and the inner wall of the outer frame of the movable mold are respectively provided with mold movable blocks which form a cavity between each other; the lower end of the inner wall of the outer frame of the stationary mold and the outer wall of the movable mold The lower ends of the inner wall of the frame are respectively provided with bottom movable blocks which form a flat bottom surface between each other; the material of the mold movable blocks and the bottom movable blocks is ceramics; a plurality of microwaves are arranged under the fixed mold outer frame and the movable mold outer frame Diverging device; the microwave diffusing device includes a microwave diffusing port located under the bottom movable block, a microwave agitator is arranged in the microwave diffusing port, and the microwave agitator is connected with a motor through a coupling; the lower end of the microwave diffusing port is connected with a microwave transmission port The end of the microwave transmission tube is provided with a microwave generator; the material of the microwave transmission tube is a stainless steel patch, including a vertical part of the microwave tube and a horizontal part of the microwave tube, and the vertical part of the microwave tube and the horizontal part of the microwave tube are inclined at 45 degrees. corner connection.

In the above-mentioned microwave heating resin sand core forming device, a plastic sealing sheet is provided on the microwave diffusing port.

In the aforementioned microwave heating resin sand core forming device, the microwave diffusing port and the microwave transmission tube are connected in a nested manner.

In the aforementioned microwave heating resin sand core forming device, lift cylinders are provided on both sides of the microwave transmission tube, and the telescopic end of the lift cylinder is connected to the outer side wall of the microwave divergence port; the microwave divergence port and the microwave transmission tube are embedded between the The length of the sleeve is greater than the stroke of the telescopic end of the lift cylinder.

In the above-mentioned microwave heating resin sand core forming device, the upper end of the fixed mold top plate is provided with a pulling cylinder, and the telescopic end of the pulling cylinder is connected with a pulling shutter, and the pulling shutter covers or opens the sand inlet hole.

In the above-mentioned microwave heating resin sand core forming device, the movable block of the mold and the outer frame of the fixed mold and the outer frame of the movable mold, and between the bottom movable block and the outer frame of the fixed mold and the outer frame of the movable mold are fixedly connected by screws.

The above-mentioned method of heating resin sand core forming device by microwave uses a microwave generator to generate microwave radiation, the microwave radiation reaches the microwave divergence port through a microwave transmission tube, and is evenly spread by the microwave stirrer in the microwave divergence port, and then the microwave radiation is emitted from the bottom. The movable block penetrates into the cavity of the movable block of the mold, and the ceramic material does not absorb microwaves to provide space for the reflection of microwave radiation in the cavity, so as to uniformly heat the resin sand entering the cavity through the sand shooting hole. , to achieve rapid heating and shorten the molding time.

In the aforementioned method of heating the resin sand core forming device by microwave, the microwave frequency generated by the microwave generator is 2450MHZ, and the heating time is 30-60S.

Compared with the prior art, the present invention changes the effective shape of the core box from the original metal structure to a ceramic structure on the structure of the original core box mold, thereby increasing the microwave reflection space in the cavity and better controlling the resin. The uniformity of microwave heating of sand is determined by using a microwave generator to generate microwave radiation. The microwave radiation passes through the microwave transmission tube to the microwave divergence port, and is evenly spread by the microwave agitator in the microwave divergence port. The microwave radiation penetrates from the bottom live block. Entering into the cavity of the movable mold block, the ceramic material does not absorb microwaves to provide space for the transmission and reflection of microwave radiation in the cavity, so as to relatively uniformly heat the resin sand entering the cavity through the sand shooting hole to achieve rapid Heating shortens molding time. Therefore, the present invention can rapidly and uniformly heat and solidify the resin sand, which greatly improves the turnover rate and production efficiency of the device. Because the resin sand heating of the present invention starts after the sand shooting is completed, the sand shooting pressure can be lower than that of the hot core box for sand shooting, so that there is no premature solidification of the resin sand near the vent hole when the hot core box is shot. As a result, the air intake is too fast and the exhaust is insufficient, which eventually leads to the failure of the core making due to poor exhaust. In addition, in the present invention, a plastic sealing sheet is arranged on the microwave dispersing port, which can prevent the crushed sand from opening the mold core from falling into the microwave dispersing port, and at the same time, it does not affect the microwave transmission and reduces the failure rate. In the present invention, a lift cylinder is installed on each side of the microwave divergence port, and the lift cylinder is used to drive the microwave divergence port to rise and fall. When microwave heating is required, the lift cylinder drives the microwave divergence port to rise, and the lifting position presses the mold to start heating. The lift cylinder drives the divergence port to descend, which is convenient for mold opening and closing. The longitudinal part of the microwave tube and the transverse part of the microwave tube of the invention are connected at an oblique angle of 45 degrees, and the length direction of the microwave tube cannot be a multiple of 30mm, which can prevent standing waves to the greatest extent and reduce microwave transmission loss. In the present invention, a pulling cylinder is arranged on the upper end of the fixed mold top plate, and a pulling ram connected to the telescopic end of the pulling cylinder is used to cover or open the sand inlet hole, so as to block the sand injection hole and prevent microwave leakage.

Description of drawings

Fig. 1 is the structural representation of the present invention;

FIG. 2 is a left-view structural schematic diagram of the present invention.

reference number

1. Fixed mold outer frame; 2. Fixed mold top plate spring; 3. Fixed mold ejector pin; 4. Fixed mold top plate; 5. Moving mold ejector pin; 6. Moving mold ejector plate; 7. Moving mold outer frame; Sand inlet hole; 9. Mould movable block; 10. Screw; 11. Bottom movable block; 12. Mould cavity; 14. Pulling gate; 15. Pulling cylinder; 16. Microwave generator; 17. Microwave transmission tube; 18. Microwave divergence port; 19. Microwave stirrer; 20. Plastic cover; 21. Motor; 22. Lifting cylinder.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments, but not as a basis for limiting the present invention.

Example: A microwave heating resin sand core forming device, as shown in Figure 1-2, includes a fixed mold outer frame 1, a fixed mold top plate 4, a spring 2, a fixed mold ejector pin 3, a fixed mold top plate 4, and a movable mold ejector pin 5. The movable mold ejector 5 plate, the movable mold outer frame 7 and the sand inlet hole 8. The inner wall of the fixed mold outer frame 1 and the inner wall of the movable mold outer frame 7 are respectively provided with a cavity 12 between them. The mold movable block 9, the mold movable block 9 has different shapes according to different types of core boxes; the lower end of the inner wall of the fixed mold outer frame 1 and the lower end of the inner wall of the movable mold outer frame 7 are respectively provided with bottoms forming a flat bottom surface. The movable block 11; the material of the mold movable block 9 and the bottom movable block 11 is ceramics, and the mold movable block 9 and the bottom movable block 11 made of ceramics are made by a conventional ceramic casting process; the mold movable block 9 and the fixed mold are made of ceramics. Between the outer frame 1 and the outer frame of the movable mold 7, the bottom movable block 11 and the outer frame of the fixed mold 1 and the outer frame of the movable mold 7 are fixedly connected by screws 10; the outer frame of the fixed mold 1 and the outer frame of the movable mold 7 There are two microwave dispersing devices below; the microwave dispersing device includes a microwave dispersing port 18 located under the bottom movable block 11, and a plastic sealing sheet 20 is arranged on the microwave dispersing port 18, which can prevent the mold-opening core and broken sand from falling into The microwave divergent port 18 does not affect the transmission of microwaves and reduces the failure rate; the microwave divergent port 18 is provided with a microwave stirrer 19, and the microwave stirrer 19 is connected with a motor 21 through a coupling, and the microwave stirrer 19 is driven by clicking Rotation; the lower end of the microwave diffusing port 18 is connected with a microwave transmission tube 17, and the end of the microwave transmission tube 17 is provided with a microwave generator 16, and the microwave generator 16 is composed of a magnetron and a power supply. The mature configuration of the manufacturer will not be described in detail here. The material of the microwave transmission tube 17 is a stainless steel patch, including a vertical part of the microwave tube and a horizontal part of the microwave tube, and the vertical part of the microwave tube and the horizontal part of the microwave tube are connected at an oblique angle of 45 degrees; the horizontal part of the microwave tube cannot be 30mm. Multiple sizes can prevent standing waves to the greatest extent and reduce microwave transmission loss. In the present invention, on the structure of the original core box mold, the effective shape of the core box is changed from the original metal structure to the ceramic structure, so that the reflection space of microwaves in the cavity 12 can be increased, and the uniformity of microwave heating of resin sand can be better controlled .

The microwave heating method of the resin sand core forming device utilizes the microwave generator 16 to generate microwave radiation. Because the phenolic resin in the resin sand has a strong thermal effect on the microwave of 2450MHZ, a magnetron of 2450MHZ is used for microwave generation. The microwave radiation passes through the microwave transmission tube 17 to the microwave divergence port 18, and is evenly dispersed by the microwave agitator 19 in the microwave divergence port 18, and the microwave radiation penetrates from the bottom movable block 11 into the cavity 12 of the mold movable block 9. Inside, the ceramic material does not absorb microwaves to provide space for the transmission and reflection of microwave radiation in the cavity 12, so as to uniformly heat the resin sand entering the cavity 12 through the sand-shooting holes, with different powers according to different products. And heating time, due to the low content of phenolic resin in resin sand, the heating speed is fast, as long as the power configuration is reasonable, it can be cured within 30-60S, so as to achieve rapid heating and shorten the molding time. Therefore, the present invention can quickly and uniformly heat and solidify the resin sand, reduce the problem that the partial resin sand is prematurely solidified due to uneven heating and block the exhaust passage, and greatly improves the turnover rate and production efficiency of the device.

Further, the microwave diffusing port 18 and the microwave transmission tube 17 are connected in a nested manner. Both sides of the microwave transmission tube 17 are provided with lift cylinders 22, and the telescopic end of the lift cylinder 22 is connected to the outer side wall of the microwave divergence port 18; The stroke of the telescopic end of the air cylinder 22 makes the microwave dispersing port 18 separate from the microwave transmission tube 17 when the microwave divergence port 18 rises. In the present invention, a lift cylinder 22 is installed on each side of the microwave divergence port 18, and the lift cylinder 22 drives the microwave divergence port 18 to rise and fall. When microwave heating is required, the lift cylinder 22 drives the microwave divergence port 18 to rise, and the lift starts to press the mold. After heating, the lifting cylinder 22 drives the diverging port to descend, which is convenient for mold opening and closing.

Further, the upper end of the fixed mold top plate 4 is provided with a pulling cylinder 15, and the telescopic end of the pulling cylinder 15 is connected with a pulling ram 14, and the pulling ram 14 covers or opens the sand inlet hole 8 to block it. Sand shot holes and the problem of preventing microwave leakage.

working principle:

The method for heating the resin sand core forming device by microwave uses the microwave generator 16 to generate microwave radiation. The microwave radiation passes through the microwave transmission tube 17 to reach the microwave divergence port 18, and is evenly spread by the microwave agitator 19 in the microwave divergence port 18. The microwave radiation penetrates from the bottom movable block 11 into the cavity 12 of the mold movable block 9. The ceramic material does not absorb microwaves to provide space for the microwave radiation to be transported and reflected in the cavity 12, so as to prevent the entry of microwave radiation through the sand shooting hole. The resin sand in the cavity 12 is uniformly heated to achieve rapid heating and shorten the molding time.

Claims (8)

1. A microwave heating resin sand core forming device, comprising a fixed mold outer frame (1), a fixed mold top plate spring (2), a fixed mold ejector pin (3), a fixed mold top plate (4), and a movable mold ejector pin (5) ), the movable mold ejector plate (6), the movable mold outer frame (7) and the sand inlet hole (8), characterized in that: the inner wall of the fixed mold outer frame (1) and the movable mold outer frame (7) The inner wall is respectively provided with a mold movable block (9) which forms a cavity (12) with each other; the lower end of the inner wall of the outer frame of the fixed mold (1) and the lower end of the inner wall of the outer frame of the movable mold (7) are respectively provided with mutual A bottom movable block (11) forming a flat bottom surface therebetween; the mold movable block (9) and the bottom movable block (11) are made of ceramics; the fixed mold outer frame (1) and the movable mold outer frame (7) A plurality of microwave dispersing devices are arranged below the microwave dispersing device; the microwave dispersing device includes a microwave dispersing port (18) located under the bottom movable block (11), and a microwave agitator (19) is arranged in the microwave dispersing port (18), and the microwave agitating The device (19) is connected with a motor (21) through a coupling; the lower end of the microwave diffusing port (18) is connected with a microwave transmission tube (17), and the end of the microwave transmission tube (17) is provided with a microwave generator (16). ); the microwave transmission tube (17) is made of stainless steel patch, including a vertical part of the microwave tube and a horizontal part of the microwave tube, and the vertical part of the microwave tube and the horizontal part of the microwave tube are connected at a 45-degree bevel. 2 . The microwave heating resin sand core forming device according to claim 1 , wherein a plastic sealing sheet ( 20 ) is provided on the microwave dispersing port ( 18 ). 3 . 3 . The microwave heating resin sand core forming device according to claim 1 , wherein the microwave diffusing port ( 18 ) and the microwave transmission tube ( 17 ) are in a nested connection. 4 . 4 . The microwave heating resin sand core forming device according to claim 3 , characterized in that: lifting cylinders ( 22 ) are provided on both sides of the microwave transmission tube ( 17 ), and the telescopic ends of the lifting cylinder ( 22 ) are connected with each other. 5 . The outer side walls of the microwave diverging port (18) are connected; the length of nesting between the microwave diverging port (18) and the microwave transmission tube (17) is greater than the stroke of the telescopic end of the lifting cylinder (22). 5 . The microwave heating resin sand core forming device according to claim 1 , wherein the upper end of the fixed die top plate ( 4 ) is provided with a pulling cylinder ( 15 ), and the telescopic end of the pulling cylinder ( 15 ) is provided. 6 . A pulling shutter (14) is connected, and the pulling shutter (14) covers or opens the sand inlet hole (8). 6 . The microwave heating resin sand core forming device according to claim 1 , characterized in that: between the movable mold block ( 9 ) and the outer frame of the fixed mold ( 1 ) and the outer frame of the movable mold ( 7 ), the bottom The movable block (11) is fixedly connected with the fixed mold outer frame (1) and the movable mold outer frame (7) by screws (10). 7. The method of microwave heating resin sand core forming device according to any one of claims 1-6, characterized in that: using a microwave generator to generate microwave radiation, the microwave radiation reaches the microwave divergence port through a microwave transmission tube, and the microwave The microwave agitator in the divergent port is evenly distributed, and the microwave radiation penetrates from the bottom movable block into the cavity of the mold movable block. The ceramic material does not absorb microwaves to provide space for the microwave radiation to be transported and reflected in the cavity. Thereby, the resin sand entering the cavity through the sand injection hole is uniformly heated, so as to realize rapid heating and shorten the molding time. 8. The method of microwave heating resin sand core forming device according to claim 7, wherein the microwave frequency generated by the microwave generator is 2450MHZ, and the heating time is 30-60S.

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