A methytetrahydrophthalic anhydride production dispensing device and a method of using the same

Abstract

The present application relates to liquid subpackaging technical field, especially to a kind of methytetrahydrophthalic anhydride production subpackaging device and its using method, including tank body, the lower end of the tank body is provided with discharge pipe, further including subpackaging mechanism being arranged on discharge pipe and anti-dripping mechanism being arranged at the lower end of discharge pipe;The subpackaging mechanism includes the shell that is integrally formed with discharge pipe, the center position of the shell is penetrated and is rotatably connected with the shaft, the outer side of the shaft is fixed with the rotating disc.The methytetrahydrophthalic anhydride droplet adhered to the lower end of discharge pipe can be sucked to the inner side of upper negative pressure cylinder and lower negative pressure cylinder after each discharge of discharge pipe by anti-dripping mechanism, methytetrahydrophthalic anhydride droplet accumulates at the bottom end of lower negative pressure cylinder, finally flows to the inner side of collection cylinder and is collected, effectively prevent methytetrahydrophthalic anhydride droplet from dropping on workbench and polluting workbench.

Description

Technical Field

[0001] This invention relates to the field of liquid dispensing technology, and in particular to a dispensing apparatus for the production of methyltetrahydrophthalic anhydride and its method of use. Background Technology

[0002] Methyltetrahydrophthalic anhydride, also known as methyltetrahydrophthalic anhydride, is an excellent organic solvent with a wide range of applications. It is mainly used in the electronics, pharmaceutical, dye, fragrance, cosmetic, paint, coating, ink, and electroplating industries. It is primarily used in the potting of unsaturated polyester resins, epoxy resin curing agents, pesticide intermediates, and dry-type transformers. During the production process, liquid methyltetrahydrophthalic anhydride needs to be dispensed in equal amounts into multiple packaging containers.

[0003] A search revealed Chinese patent CN216970086U, which discloses a liquid quantitative dispensing device, including a dispensing platform, a U-shaped plate near the bottom of the front end face of the dispensing platform, a transparent plate embedded in the front end face of the dispensing cylinder, a baffle in the annular groove, a motor behind the dispensing cylinder, and a dispensing roller at the end of the output shaft. A dividing block is provided on the outer circumference of the dispensing roller, a liquid inlet is embedded near the top of the outer circumference of the dispensing cylinder, and a drain pipe is embedded near the bottom of the outer circumference of the dispensing cylinder.

[0004] Based on the above research and combined with the actual problems, it was found that: when dispensing liquids with a certain viscosity, the end of the discharge pipe of the existing dispensing device is prone to some liquid adhering to it. If the adhering liquid is not cleaned in time, the liquid can easily drip onto the worktable, causing contamination of the worktable, or drip into the next packaging tank, resulting in unequal liquid content in two adjacent packaging tanks, which increases the dispensing error. Summary of the Invention

[0005] The purpose of this invention is to provide a dispensing apparatus and its method for producing methyltetrahydrophthalic anhydride, in order to solve the problems mentioned in the background art.

[0006] The technical solution of the present invention is: a dispensing device for the production of methyltetrahydrophthalic anhydride, comprising a tank body, a discharge pipe at the lower end of the tank body, a dispensing mechanism disposed on the discharge pipe, and an anti-drip mechanism disposed at the lower end of the discharge pipe; the dispensing mechanism comprises a shell integrally formed with the discharge pipe, a rotating shaft rotatably connected through the center of the shell body, a turntable fixed on the outer side of the rotating shaft, the turntable being rotatably adapted to the inner side of the shell body, and a plurality of dispensing cavities arranged in a circular pattern on the outer side of the turntable, and a driving mechanism for driving the rotating shaft and the turntable to rotate at equal angles; the anti-drip mechanism comprises an upper negative pressure cylinder fixed to the lower end of the outer side of the discharge pipe, a lower negative pressure cylinder connected to the lower end of the upper negative pressure cylinder, a plurality of liquid suction holes arranged in a circular pattern at the lower edge of the lower end of the lower negative pressure cylinder, a negative pressure mechanism connected to one side of the upper negative pressure cylinder, and a check mechanism disposed on the inner side of the upper and lower negative pressure cylinders.

[0007] Preferably, the negative pressure mechanism includes an air extraction cylinder, one end of which is connected to a connecting pipe and an exhaust pipe. One end of the connecting pipe is connected to the inner side of the upper negative pressure cylinder. A piston plate is slidably connected to the inner side of the air extraction cylinder. One end of the piston plate is fixed with a pull rod extending to the outside. An electric cylinder is installed on the outer side of the air extraction cylinder. The telescopic end of the electric cylinder is fixedly connected to one end of the pull rod. A one-way valve is provided on the inner side of both the connecting pipe and the exhaust pipe.

[0008] Preferably, the drive mechanism includes a gear rotatably connected to one end of the outer side of the shaft, a guide bar fixed to the outer side of the housing, a rack that meshes with the gear slidably connected to the outer side of the guide bar, a lever fixed to one side of the rack, and a baffle fixed to the lower side of the rack at the middle position.

[0009] Preferably, the driving mechanism further includes a first limiting block and a second limiting block fixed on the outside of the housing at positions on both sides of the baffle. Each of the first limiting block and the second limiting block is equipped with a limit switch on one side, and both limit switches are electrically connected to the control circuit of the electric cylinder.

[0010] Preferably, a one-way bearing is fixedly sleeved on one outer end of the rotating shaft, and the gear is fixedly sleeved on the outer side of the one-way bearing.

[0011] Preferably, the check valve mechanism includes a fixed ring fixed to the lower end of the inner side of the upper negative pressure cylinder and a sliding ring slidably disposed on the inner side of the lower negative pressure cylinder. The upper end of the sliding ring is connected to a spring, and a pressure rod is fixed at the lower end of the sliding ring corresponding to the position of each suction hole. A sealing ball for sealing the suction hole is fixed at the lower end of each pressure rod.

[0012] Preferably, each of the liquid suction holes has a spherical groove at its upper end that is adapted to the sealing ball.

[0013] Preferably, each of the liquid suction holes has a chamfer at its lower end, and the lower end of the lower negative pressure cylinder has an annular groove that communicates with the multiple liquid suction holes.

[0014] Preferably, the lower end of the lower negative pressure cylinder is threadedly connected to a collecting cylinder.

[0015] The present invention also provides a method of using a dispensing device for the production of methyltetrahydrophthalic anhydride, comprising the following steps: Step 1: During dispensing, the rack moves to one end, causing the gear to rotate. Under the action of the one-way bearing, the gear does not drive the shaft to rotate. When the rack moves the baffle to its limit at one end, the baffle contacts the first limit block and cannot move further. Then, the rack moves in the opposite direction, causing the gear to rotate in the opposite direction. Under the action of the one-way bearing, the shaft drives the turntable to rotate in the opposite direction. When the baffle contacts the second limit block at the other end, it cannot move further. The rack moves from one end to the other, causing the gear, shaft, and turntable to rotate in both directions within the range of 0°-90°. Each time the turntable rotates 90°, it drives the four dispensing cavities to rotate 90° synchronously. In actual dispensing, each time the turntable rotates 90°, the methyltetrahydrophthalic anhydride liquid can flow out through the discharge pipe. Step 2: When the rack in the drive mechanism moves to one end limit, its lower baffle contacts a limit switch on the first limit block, triggering the circuit in the limit switch. Upon receiving the signal from this limit switch, the control circuit controls the retraction end of the electric cylinder of the negative pressure mechanism to retract. The electric cylinder drives the piston plate to move to the left via a pull rod. When the piston plate moves to the left, the air inside the suction cylinder is discharged through the exhaust pipe. When the rack moves in the opposite direction to the other end limit, its lower baffle contacts another limit switch on the second limit block, triggering... In another limit switch circuit, after receiving the signal from this limit switch, the control circuit controls the extension end of the electric cylinder of the negative pressure mechanism to extend, driving the piston plate to move to the right, drawing the air inside the upper and lower negative pressure cylinders into the air extraction cylinder through the pipe, so that the upper and lower negative pressure cylinders form a negative pressure. Outside air flows into the inner side of the lower negative pressure cylinder at high speed through multiple liquid suction holes. Methyltetrahydrophthalic anhydride droplets adhering to the lower edge of the discharge pipe flow into the inner side of the lower negative pressure cylinder with the high-speed airflow through multiple liquid suction holes. Step 3: By setting up a check valve mechanism, after the air pressure inside and outside the lower negative pressure cylinder is balanced, the sliding ring inside applies a certain downward pressure to multiple pressure rods and multiple sealing balls under the elastic force of the spring, so that multiple sealing balls press against the inner side of multiple spherical grooves to achieve sealing and prevent the methyltetrahydrophthalic anhydride liquid inside the lower negative pressure cylinder from flowing out.

[0016] The present invention provides an improved dispensing apparatus and method for the production of methyltetrahydrophthalic anhydride, which, compared with the prior art, has the following improvements and advantages: Firstly, this invention, through the setting of a driving mechanism, allows the rack to move from one end to the other each time, driving the gear to rotate 90°, thereby driving the rotating shaft and turntable to rotate 90°. The turntable can drive multiple dispensing cavities to rotate 90°. In actual dispensing operations, only the turntable needs to be rotated 90° each time to allow the methyltetrahydrophthalic anhydride liquid to flow out through the discharge pipe, achieving rapid dispensing. Since each dispensing cavity has the same volume, an equal amount of methyltetrahydrophthalic anhydride liquid can be discharged each time, improving the accuracy of dispensing.

[0017] Secondly, this invention uses an anti-drip mechanism to draw the methyltetrahydrophthalic anhydride droplets adhering to the lower end of the discharge pipe after each discharge, drawing them into the inner sides of the upper and lower negative pressure cylinders. The methyltetrahydrophthalic anhydride droplets accumulate at the bottom of the lower negative pressure cylinder and eventually flow into the inner side of the collection cylinder for collection. This effectively prevents methyltetrahydrophthalic anhydride droplets from falling onto the workbench and contaminating it, or from dripping into the next packaging can, thus avoiding significant errors in the methyltetrahydrophthalic anhydride liquid content in different packaging cans. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a first-view structural diagram of the present invention; Figure 2 This is a schematic diagram of the first partial cross-sectional structure of the present invention; Figure 3 This is a schematic cross-sectional view of the overall structure of the present invention; Figure 4 This is a schematic diagram of the second partial cross-sectional structure of the present invention; Figure 5 This is a cross-sectional view of the lower negative pressure cylinder in this invention; Figure 6 This is a schematic diagram of the second perspective structure of the present invention; Figure 7 For the present invention Figure 6 A magnified structural diagram of point A in the middle.

[0020] Figure label: 1. Tank body; 2. Discharge pipe; 3. Shell; 4. Rotating shaft; 5. Turntable; 6. Dispensing cavity; 101. Rack; 102. Gear; 103. Guide bar; 104. First limit block; 105. Second limit block; 106. Baffle; 107. Limit switch; 201. Upper negative pressure cylinder; 202. Lower negative pressure cylinder; 203. Suction hole; 204. Fixing ring; 205. Sliding ring; 206. Spring; 207. Pressure rod; 208. Sealing ball; 209. Spherical groove; 210. Annular groove; 211. Collection cylinder; 301. Vacuum cylinder; 302. Connecting pipe; 303. Exhaust pipe; 304. Piston plate; 305. Pull rod; 306. Electric cylinder. Detailed Implementation

[0021] The present invention will now be described in detail, and the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] This invention provides an improved dispensing apparatus for the production of methyltetrahydrophthalic anhydride and its method of use. The technical solution of this invention is as follows: Example 1: like Figures 1 to 7 As shown, this embodiment of the invention provides a dispensing device for the production of methyltetrahydrophthalic anhydride, including a tank 1, a discharge pipe 2 at the lower end of the tank 1, a dispensing mechanism mounted on the discharge pipe 2, and an anti-drip mechanism at the lower end of the discharge pipe 2; the dispensing mechanism includes a shell 3 integrally formed with the discharge pipe 2, a rotating shaft 4 rotatably connected through the center of the shell 3, a turntable 5 fixed to the outside of the rotating shaft 4, the turntable 5 being rotatably adapted to the inner side of the shell 3, and multiple dispensing cavities 6 arranged circumferentially on the outer side of the turntable 5. The system includes a drive mechanism that drives the rotating shaft 4 and the turntable 5 to rotate at equal angles; the anti-drip mechanism includes an upper negative pressure cylinder 201 fixed to the lower end of the outer side of the discharge pipe 2, a lower negative pressure cylinder 202 connected to the lower end of the upper negative pressure cylinder 201, a plurality of circumferentially arranged liquid suction holes 203 opened at the lower end of the lower negative pressure cylinder 202 at the edge position, a collection cylinder 211 threadedly connected to the lower end of the lower negative pressure cylinder 202, a negative pressure mechanism connected to one side of the upper negative pressure cylinder 201, and a check mechanism provided on the inner side of the upper negative pressure cylinder 201 and the lower negative pressure cylinder 202.

[0023] Furthermore, the negative pressure mechanism includes an air extraction cylinder 301, one end of which is connected to a connecting pipe 302 and an exhaust pipe 303. One end of the connecting pipe 302 is connected to the inner side of the upper negative pressure cylinder 201. A piston plate 304 is slidably connected to the inner side of the air extraction cylinder 301. One end of the piston plate 304 is fixed with a pull rod 305 extending to the outside. An electric cylinder 306 is installed on the outer side of the air extraction cylinder 301. The telescopic end of the electric cylinder 306 is fixedly connected to one end of the pull rod 305. One-way valves are provided on the inner sides of both the connecting pipe 302 and the exhaust pipe 303. The negative pressure mechanism creates a negative pressure inside the upper negative pressure cylinder 201 and the lower negative pressure cylinder 202, allowing outside air to flow into the inside of the upper negative pressure cylinder 201 and the lower negative pressure cylinder 202 through multiple liquid suction holes 203. At the same time, the airflow mixes with the adhering liquid droplets and enters the inside of the upper negative pressure cylinder 201 and the lower negative pressure cylinder 202.

[0024] Furthermore, the drive mechanism includes a gear 102 unidirectionally rotatably connected to one end of the outer side of the rotating shaft 4, a guide bar 103 fixed to the outer side of the housing 3, a rack 101 slidably connected to the outer side of the guide bar 103 and meshing with the gear 102, a lever fixed to one side of the rack 101, and a baffle 106 fixed to the lower side of the rack 101 at the middle position. The drive mechanism also includes a first limiting block 104 and a second limiting block 105 fixed to the outer side of the housing 3 at the positions on both sides of the baffle 106. A limit switch 107 is installed on one side of both the first limiting block 104 and the second limiting block 105. Both limit switches 107 are electrically connected to the control circuit of the electric cylinder 306. A one-way bearing is fixedly sleeved on one end of the outer side of the rotating shaft 4, and the gear 102 is fixedly sleeved on the outer side of the one-way bearing. The drive mechanism is used to drive the rotating shaft 4 and the turntable 5 to rotate, so that they can rotate within the range of 0-90°, thereby driving multiple dispensing cavities 6 to rotate at equal angles, which facilitates the dispensing of methyltetrahydrophthalic anhydride liquid in equal amounts.

[0025] Furthermore, the check mechanism includes a fixed ring 204 fixed to the lower end of the inner side of the upper negative pressure cylinder 201 and a sliding ring 205 slidably disposed inside the lower negative pressure cylinder 202. The upper end of the sliding ring 205 is connected to a spring 206, and the lower end of the sliding ring 205 is fixed with a pressure rod 207 at the position corresponding to each liquid suction hole 203. The lower end of each pressure rod 207 is fixed with a sealing ball 208 for sealing the liquid suction hole 203. By setting a check mechanism, after the air pressure inside and outside the lower negative pressure cylinder 202 is balanced, the sliding ring 205, under the elastic force of the spring 206, applies a certain downward pressure to multiple pressure rods 207 and multiple sealing balls 208, so that the multiple sealing balls 208 press against the inner side of multiple spherical grooves 209 to achieve sealing, thus preventing the methyltetrahydrophthalic anhydride liquid inside the lower negative pressure cylinder 202 from flowing out.

[0026] Furthermore, each suction hole 203 is provided with a spherical groove 209 at its upper end that is compatible with the sealing ball 208; This can prevent the methyltetrahydrophthalic anhydride liquid collected inside the lower negative pressure cylinder 202 from flowing out from the gap between the sealing ball 208 and the spherical groove 209.

[0027] Furthermore, each suction hole 203 has a chamfer at its lower end, and the lower negative pressure cylinder 202 has an annular groove 210 that communicates with multiple suction holes 203 at its lower end. The lower end of the negative pressure cylinder 202 is provided with an annular groove 210 that communicates with multiple liquid suction holes 203. When methyltetrahydrophthalic anhydride droplets accumulate near individual liquid suction holes 203, under the action of airflow, the methyltetrahydrophthalic anhydride droplets can flow evenly to the inner side of several adjacent liquid suction holes 203 through the annular groove 210, thereby improving the collection efficiency of methyltetrahydrophthalic anhydride droplets and reducing the risk of methyltetrahydrophthalic anhydride droplets dripping.

[0028] Example 2: This embodiment also provides a method for using a dispensing device for the production of methyltetrahydrophthalic anhydride, including the following steps: Step 1: During dispensing, the rack 101 moves to one end, driving the gear 102 to rotate. Under the action of the one-way bearing, the gear 102 will not drive the rotating shaft 4 to rotate. When the rack 101 drives the baffle 106 to move to the limit at one end, the baffle 106 contacts the first limiting block 104 and cannot move further. Then the rack 101 moves in the opposite direction, driving the gear 102 to rotate in the opposite direction. Under the action of the one-way bearing, the rotating shaft 4 drives the turntable 5 to rotate in the opposite direction. When the baffle 106 contacts the second limiting block 105 at the other end, it cannot move further. The rack 101 moves from one end to the other end, causing the gear 102, rotating shaft 4, and turntable 5 to rotate in both directions within the range of 0°-90°. When the turntable 5 rotates 90° each time, it drives the four dispensing cavities 6 to rotate 90° synchronously. In actual dispensing, each time the turntable 5 rotates 90°, the methyltetrahydrophthalic anhydride liquid can flow out through the discharge pipe 2. Step 2: When the rack 101 in the drive mechanism moves to one end limit, its lower baffle 106 contacts a limit switch 107 on the first limit block 104, triggering the circuit in the limit switch 107. After receiving the signal from this limit switch 107, the control circuit controls the extension end of the electric cylinder 306 of the negative pressure mechanism to retract. The electric cylinder 306 drives the piston plate 304 to move to the left through the pull rod 305. When the piston plate 304 moves to the left, the air inside the suction cylinder 301 is discharged through the exhaust pipe 303. When the rack 101 moves in the opposite direction to the other end limit, its lower baffle 106 contacts another limit switch 107 on the second limit block 105. When the circuit in another limit switch 107 is triggered, the control circuit receives the signal from the limit switch 107 and controls the extension end of the electric cylinder 306 of the negative pressure mechanism to extend, driving the piston plate 304 to move to the right. This draws the air inside the upper negative pressure cylinder 201 and the lower negative pressure cylinder 202 into the air extraction cylinder 301 through the pipe 302, creating a negative pressure inside the upper negative pressure cylinder 201 and the lower negative pressure cylinder 202. Outside air flows rapidly into the inside of the lower negative pressure cylinder 202 through multiple suction holes 203. Methyltetrahydrophthalic anhydride droplets adhering to the lower edge of the discharge pipe 2 flow into the inside of the lower negative pressure cylinder 202 with the high-speed airflow through multiple suction holes 203. Step 3: By setting a check valve, after the air pressure inside and outside the lower negative pressure cylinder 202 is balanced, the sliding ring 205, under the elastic force of the spring 206, applies a certain downward pressure to multiple pressure rods 207 and multiple sealing balls 208, so that the multiple sealing balls 208 press against the inner side of multiple spherical grooves 209 to achieve sealing, thus preventing the methyltetrahydrophthalic anhydride liquid inside the lower negative pressure cylinder 202 from flowing out.

[0029] Working principle: During use, methyltetrahydrophthalic anhydride is poured into the interior of container 1. Each time it is dispensed, the lever of the drive mechanism is held to move rack 101 to one end. Rack 101 drives gear 102 to rotate via its teeth. Since gear 102 is connected to shaft 4 via a one-way bearing, gear 102 will not drive shaft 4 to rotate at this time. When rack 101 moves baffle 106 to one end limit, baffle 106 will contact the first limit block 104, thus preventing further movement. Then rack 101 is moved in the opposite direction, driving gear 102 to rotate in the opposite direction. At this time, gear 102 can drive shaft 4 to rotate in the opposite direction via the one-way bearing. Shaft 4 drives turntable 5 to rotate in the opposite direction. When baffle 106 contacts the second limit block 104 at the other end... When the position block 105 contacts, the rack 101 moves to the other limit. The distance between the two limits allows the gear 102 and the rotating shaft 4 to rotate in both directions within the range of 0°-90°, thereby allowing the turntable 5 to rotate in both directions within the range of 0°-90°. When the turntable 5 rotates 90° each time, it can drive the four dispensing cavities 6 to rotate 90° synchronously. When each dispensing cavity 6 rotates to the top, the methyltetrahydrophthalic anhydride liquid inside the tank 1 can fill the inside of this dispensing cavity 6. The methyltetrahydrophthalic anhydride liquid in this dispensing cavity 6 can flow out through the discharge pipe 2 after rotating 90° twice. In actual dispensing, it is only necessary to drive the turntable 5 to rotate 90° each time to allow the methyltetrahydrophthalic anhydride liquid to flow out through the discharge pipe 2, thus achieving the function of rapid dispensing. Because methyltetrahydrophthalic anhydride liquid has a certain viscosity at low temperatures, after each dispensing, methyltetrahydrophthalic anhydride droplets will adhere to the lower edge of the discharge pipe 2. If the methyltetrahydrophthalic anhydride droplets are not cleaned in time, they will drip onto the workbench and contaminate the workbench, or drip into the next packaging can, resulting in a large error in the methyltetrahydrophthalic anhydride liquid content in different packaging cans. The above problem is solved by setting up a drip-proof mechanism. When the drive mechanism is operated, when the rack 101 in the drive mechanism moves to one end limit, the baffle 106 on its lower side contacts a limit switch 107 on the first limit block 104, thereby triggering the circuit in the limit switch 107. After receiving the signal from this limit switch 107, the control circuit controls the extension end of the electric cylinder 306 of the negative pressure mechanism to retract. The electric cylinder 306 drives the piston plate 304 to move to the left through the pull rod 305. It should be noted that the conduction direction of the one-way valve located inside the exhaust pipe 303 points to the outside of the suction cylinder 301, and the conduction direction of the one-way valve inside the pipe 302 points to the inside of the suction cylinder 301. When the piston plate 304 moves to the left, the air inside the suction cylinder 301 can be discharged through the exhaust pipe 303. When the rack 101 moves in the opposite direction to the other end limit, the baffle 106 on its lower side contacts the second limit block 105. When another limit switch 107 is contacted, the circuit in the other limit switch 107 is triggered. After receiving the signal from this limit switch 107, the control circuit controls the extension end of the electric cylinder 306 of the negative pressure mechanism to extend, thereby driving the piston plate 304 to move to the right. The air inside the upper negative pressure cylinder 201 and the lower negative pressure cylinder 202 is drawn into the air extraction cylinder 301 through the pipe 302, thereby creating a negative pressure inside the upper negative pressure cylinder 201 and the lower negative pressure cylinder 202. The outside air will flow into the inside of the lower negative pressure cylinder 202 at high speed through multiple liquid suction holes 203. The methyltetrahydrophthalic anhydride droplets adhering to the lower edge of the discharge pipe 2 will flow into the inside of the lower negative pressure cylinder 202 with the high-speed airflow through multiple liquid suction holes 203. This can effectively prevent the methyltetrahydrophthalic anhydride droplets adhering to the lower end of the discharge pipe 2 from falling, preventing contamination of the workbench, and preventing them from falling into the next packaging can and increasing the dispensing error. In the check mechanism, the sliding ring 205, under the elastic force of the spring 206, applies a certain downward pressure to the multiple pressure rods 207 and multiple sealing balls 208, thereby pressing the multiple sealing balls 208 against the inner sides of the multiple spherical grooves 209. When external air flows into the inner side of the downward negative pressure cylinder 202 through the multiple suction holes 203, the air pressure can push the multiple sealing balls 208 upward, thereby creating a certain gap between the sealing balls 208 and the spherical grooves 209, allowing airflow and methyl... Tetrahydrophthalic anhydride droplets enter the inner side of the lower negative pressure cylinder 202. After the air pressure inside and outside the lower negative pressure cylinder 202 is balanced, under the elastic force of the spring 206, multiple sealing balls 208 press against the inner side of multiple spherical grooves 209 to achieve sealing, preventing the methyltetrahydrophthalic anhydride liquid inside the lower negative pressure cylinder 202 from flowing out. A collection cylinder 211 is threadedly connected to one side of the lower negative pressure cylinder 202. The methyltetrahydrophthalic anhydride liquid accumulated inside the lower negative pressure cylinder 202 will flow into the collection cylinder 211 and be collected. The lower end of the negative pressure cylinder 202 is provided with an annular groove 210 that communicates with multiple liquid suction holes 203. When methyltetrahydrophthalic anhydride droplets accumulate near individual liquid suction holes 203, under the action of airflow, the methyltetrahydrophthalic anhydride droplets can flow evenly to the inner side of several adjacent liquid suction holes 203 through the annular groove 210, thereby improving the collection efficiency of methyltetrahydrophthalic anhydride droplets and reducing the risk of methyltetrahydrophthalic anhydride droplets dripping.

[0030] The foregoing description enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A dispensing device for the production of methyltetrahydrophthalic anhydride, comprising a tank (1), wherein a discharge pipe (2) is provided at the lower end of the tank (1), characterized in that, It also includes a dispensing mechanism installed on the discharge pipe (2) and an anti-drip mechanism installed at the lower end of the discharge pipe (2); The dispensing mechanism includes a housing (3) integrally formed with the feeding pipe (2), a rotating shaft (4) is rotatably connected through the center of the housing (3), a turntable (5) is fixed on the outside of the rotating shaft (4), the turntable (5) is rotatably adapted to the inside of the housing (3), and multiple dispensing cavities (6) arranged in a circle are opened on the outside of the turntable (5), and a driving mechanism is also included to drive the rotating shaft (4) and the turntable (5) to rotate at the same angle; The anti-drip mechanism includes an upper negative pressure cylinder (201) fixed to the lower end of the outer side of the discharge pipe (2). The lower end of the upper negative pressure cylinder (201) is connected to a lower negative pressure cylinder (202). The lower end of the lower negative pressure cylinder (202) is provided with a plurality of circumferentially arranged liquid suction holes (203) at the edge position. A negative pressure mechanism is connected to one side of the upper negative pressure cylinder (201). A check mechanism is provided on the inner side of the upper negative pressure cylinder (201) and the lower negative pressure cylinder (202).

2. The dispensing apparatus for the production of methyltetrahydrophthalic anhydride according to claim 1, characterized in that: The negative pressure mechanism includes an air extraction cylinder (301), one end of which is connected to a connecting pipe (302) and an exhaust pipe (303). One end of the connecting pipe (302) is connected to the inner side of the upper negative pressure cylinder (201). A piston plate (304) is slidably connected to the inner side of the air extraction cylinder (301). One end of the piston plate (304) is fixed with a pull rod (305) extending to the outside. An electric cylinder (306) is installed on the outer side of the air extraction cylinder (301). The telescopic end of the electric cylinder (306) is fixedly connected to one end of the pull rod (305). A one-way valve is provided on the inner side of both the connecting pipe (302) and the exhaust pipe (303).

3. A dispensing apparatus for the production of methyltetrahydrophthalic anhydride according to claim 2, characterized in that: The drive mechanism includes a gear (102) unidirectionally rotatably connected to one end of the outer side of the shaft (4) and a guide bar (103) fixed to the outer side of the housing (3). The guide bar (103) is slidably connected to a rack (101) that meshes with the gear (102). A lever is fixed to one side of the rack (101), and a baffle (106) is fixed to the lower side of the rack (101) at the middle position.

4. A dispensing apparatus for the production of methyltetrahydrophthalic anhydride according to claim 3, characterized in that: The drive mechanism also includes a first limiting block (104) and a second limiting block (105) fixed on the outside of the housing (3) at positions on both sides of the baffle (106). Each of the first limiting block (104) and the second limiting block (105) is equipped with a limit switch (107), and both limit switches (107) are electrically connected to the control circuit of the electric cylinder (306).

5. A dispensing apparatus for the production of methyltetrahydrophthalic anhydride according to claim 3, characterized in that: One-way bearing is fixedly sleeved on one side of the rotating shaft (4), and gear (102) is fixedly sleeved on the outside of the one-way bearing.

6. A dispensing apparatus for the production of methyltetrahydrophthalic anhydride according to claim 1, characterized in that: The check valve mechanism includes a fixed ring (204) fixed to the lower end of the inner side of the upper negative pressure cylinder (201) and a sliding ring (205) slidably disposed inside the lower negative pressure cylinder (202). The upper end of the sliding ring (205) is connected to a spring (206), and the lower end of the sliding ring (205) is fixed with a pressure rod (207) at the position corresponding to each suction hole (203). The lower end of each pressure rod (207) is fixed with a sealing ball (208) for sealing the suction hole (203).

7. A dispensing apparatus for the production of methyltetrahydrophthalic anhydride according to claim 6, characterized in that: Each of the suction holes (203) is provided with a spherical groove (209) at its upper end that is adapted to the sealing ball (208).

8. A dispensing apparatus for the production of methyltetrahydrophthalic anhydride according to claim 1, characterized in that: Each of the suction holes (203) has a chamfer at its lower end, and the lower end of the negative pressure cylinder (202) has an annular groove (210) that communicates with the multiple suction holes (203).

9. A dispensing apparatus for the production of methyltetrahydrophthalic anhydride according to claim 1, characterized in that: The lower end of the negative pressure cylinder (202) is threadedly connected to a collection cylinder (211).

10. A method of using a dispensing apparatus for the production of methyltetrahydrophthalic anhydride, the dispensing apparatus for the production of methyltetrahydrophthalic anhydride according to any one of claims 1-9, characterized in that, Includes the following steps: Step 1: During the disassembly process, the rack (101) is moved to one end, causing the gear (102) to rotate. Under the action of the one-way bearing, the gear (102) will not drive the shaft (4) to rotate. When the rack (101) drives the baffle (106) to move to one end limit, the baffle (106) contacts the first limit block (104) and cannot continue to move. Then, the rack (101) is moved in the opposite direction, causing the gear (102) to rotate in the opposite direction. Under the action of the one-way bearing, the shaft (4) rotates... The rotating disk (5) rotates in the opposite direction. When the baffle (106) contacts the second limiting block (105) at the other end, it cannot continue to move. The rack (101) moves from one end to the other end, so that the gear (102), the rotating shaft (4) and the rotating disk (5) rotate in the forward and reverse directions within the range of 0°-90°. When the rotating disk (5) rotates 90° each time, it drives the four dispensing cavities (6) to rotate 90° synchronously. In actual dispensing, the rotating disk (5) rotates 90° each time, so that the methyltetrahydrophthalic anhydride liquid can flow out through the discharge pipe (2). Step 2: When the rack (101) in the drive mechanism moves to one end limit, its lower baffle (106) contacts a limit switch (107) on the first limit block (104), triggering the circuit in the limit switch (107). After receiving the signal from this limit switch (107), the control circuit controls the extension end of the electric cylinder (306) of the negative pressure mechanism to retract. The electric cylinder (306) drives the piston plate (304) to move to the left through the pull rod (305). When the piston plate (304) moves to the left, the air inside the suction cylinder (301) is discharged through the exhaust pipe (303). When the rack (101) moves in the opposite direction to the other end limit, its lower baffle (106) contacts another limit switch (107) on the second limit block (105). When the circuit in another limit switch (107) is triggered, the control circuit receives the signal from this limit switch (107) and controls the extension end of the electric cylinder (306) of the negative pressure mechanism to extend, driving the piston plate (304) to move to the right, drawing the air inside the upper negative pressure cylinder (201) and the lower negative pressure cylinder (202) into the air extraction cylinder (301) through the pipe (302), so that the upper negative pressure cylinder (201) and the lower negative pressure cylinder (202) form a negative pressure. The outside air flows into the inside of the lower negative pressure cylinder (202) at high speed through multiple suction holes (203), and the methyltetrahydrophthalic anhydride droplets adhering to the lower edge of the discharge pipe (2) flow into the inside of the lower negative pressure cylinder (202) with the high-speed airflow through multiple suction holes (203). Step 3: By setting a check mechanism, after the air pressure inside and outside the lower negative pressure cylinder (202) is balanced, the sliding ring (205) applies a certain downward pressure to multiple pressure rods (207) and multiple sealing balls (208) under the elastic force of the spring (206), so that multiple sealing balls (208) press against the inner side of multiple spherical grooves (209) to achieve sealing, and prevent the methyltetrahydrophthalic anhydride liquid inside the lower negative pressure cylinder (202) from flowing out.

Images