A suction control device for pulp molded products

Abstract

The utility model provides a kind of pulp suction control device of pulp molding forming, comprising: zoned suction mold, connect vacuum buffer tank by suction vacuum pipe, the other end of vacuum buffer tank is connected main vacuum pump by pressure balance pipe;Suction vacuum pipe includes multiple, each suction vacuum pipe is equipped with solenoid valve group, each solenoid valve group is connected control module respectively by data bus.The utility model is through dynamic adjustment vacuum suction process parameter and mould structure optimization, realize the method of accurate control of suction volume, for improving product uniformity, reduce energy consumption and adapt to the production demand of multi-specification product.

Description

Technical Field

[0001] This utility model relates to the field of pulp molding technology, and in particular to a pulp suction control device for pulp molding. Background Technology

[0002] Pulp molding is a three-dimensional papermaking technology that uses waste paper as raw material and molds it into paper products of a certain shape using special molds on a molding machine. Existing pulp molding suction control systems use solenoid valve assemblies to control vacuum pressure during operation, thereby realizing the pulp molding process. For example, Chinese patent CN217556564U provides a pneumatic control system for a pulp molding machine, including a control valve assembly. The control valve assembly includes a base and an air collection seat. The air collection seat is provided with an air collection chamber, which is connected to a cylinder via a pipe. The base is provided with an air inlet chamber and an air outlet chamber. The air inlet chamber is connected to a pressurized air source via a connecting pipe, and the air outlet chamber is connected to the outdoor environment via a silencer pipe. Multiple three-position five-way valves are provided between the base and the air collection seat. When the three-position five-way valves are in the air inlet position, the air inlet chamber is connected to the air collection chamber. When the three-position five-way valves are in the air outlet position, the air outlet chamber is connected to the air collection chamber. When the three-position five-way valves are in the stop position, the connection between the air collection chamber, the air inlet chamber, and the air outlet chamber is disconnected.

[0003] While the above solution addresses issues such as poor speed control, excessive equipment vibration, and high exhaust noise, in practical applications, the slurry intake control relies on fixed vacuum and time parameters, leading to the following problems: 1. Product defects: Uneven fiber deposition causes thickness fluctuations (±8% or more), affecting mechanical properties; 2. High energy consumption: Excessively prolonged suction time leads to energy waste (energy consumption per unit product increases by 15-25%). 3. Poor adaptability: Manual parameter adjustment is inefficient and difficult to match the requirements of complex mold structures or high-precision products.

[0004] Existing technologies lack real-time monitoring and closed-loop control of the dynamic deposition of fibers during the pulping process, which restricts product quality and production efficiency. Utility Model Content

[0005] This invention provides a pulp suction control device for pulp molding, which solves the problem of lack of real-time monitoring and closed-loop control of fiber dynamic deposition during the pulp suction process, thus restricting product quality and production efficiency.

[0006] This utility model provides a pulp suction control device for pulp molding, comprising: a partitioned pulp suction mold, a vacuum buffer tank connected to a pulp suction vacuum tube, and the other end of the vacuum buffer tank connected to a main vacuum pump through a pressure balance tube; The vacuum tubes for slurry suction consist of multiple tubes, each equipped with a solenoid valve assembly. Each solenoid valve assembly is connected to the control module via a data bus.

[0007] Preferably, the partitioned suction mold includes at least three suction molds, each of which is connected to a vacuum buffer tank via a suction vacuum tube.

[0008] Preferably, the number of solenoid valve assemblies corresponds one-to-one with the number of suction molds.

[0009] Preferably, the solenoid valve assembly is a three-way solenoid valve, with one end connected to the slurry suction mold via a slurry suction vacuum pipe, the other end connected to the vacuum buffer tank via a slurry suction vacuum pipe, and the third end connected to the forward and reverse blowing pipes.

[0010] Preferably, the vacuum tube for suction is a transparent PVC pipe with an optical fiber flow rate sensor installed on its inner wall; the output end of the optical fiber flow rate sensor is electrically connected to the control module.

[0011] Preferably, the partitioned suction mold consists of at least 3-5 suction molds, each suction mold being an independent vacuum chamber, and the cavity of each independent vacuum chamber being independently connected to the vacuum buffer tank via an electromagnetic valve.

[0012] Preferably, multiple laser thickness gauges are evenly distributed on the circumferential inner wall of the partitioned suction mold; each laser thickness gauge is electrically connected to the control module via wires.

[0013] Preferably, each independent vacuum chamber is an independently controlled region, and each independently controlled region includes a main cavity region and an edge reinforcement region; the vacuum levels of the main cavity region and the edge reinforcement region are different.

[0014] Preferably, the reinforcing rib area is provided with a multi-micropore array, the micropore array including multiple micropores, each micropore having a diameter of 0.8-1.2mm.

[0015] Preferably, the main cavity area includes multiple gradient holes, each with a diameter that gradually decreases from large to small and is evenly distributed, with each gradient hole having a diameter of 1.5-2.5 mm.

[0016] The working principle and beneficial effects of this utility model are as follows: This invention provides a pulp suction control device for pulp molding, which solves the problem of lack of real-time monitoring and closed-loop control of fiber dynamic deposition during the pulp suction process, thus restricting product quality and production efficiency.

[0017] This utility model provides a pulp suction control device for pulp molding, including: a partitioned pulp suction mold, connected to a vacuum buffer tank through a pulp suction vacuum tube, the other end of the vacuum buffer tank being connected to a main vacuum pump through a pressure balance tube; the pulp suction vacuum tube includes multiple tubes, each of which is equipped with an electromagnetic valve group, and each electromagnetic valve group is connected to a control module through a data bus.

[0018] This invention solves the problem of uncontrollable slurry absorption by dynamic vacuum regulation, coordinated optimization of process parameters and innovative mold structure, achieving a product thickness deviation of ≤±3%, a 30% improvement in the stability of wet blank moisture content, a 15-30% reduction in unit energy consumption, and a more than 50% extension of mold life; it also supports high-precision molding of complex geometric molds (such as multi-curved surfaces and reinforced rib structures).

[0019] In this invention, the fiber interlacing strength is improved through dynamic vacuum gradient control technology. Specifically, based on the fiber concentration and mold structure characteristics, the vacuum level is adjusted in stages (low vacuum slurry laying in the early stage and high pressure dewatering in the later stage) to avoid fiber breakage. A pulsed vacuum waveform (0.5s high pressure / 0.2s low pressure alternation) is introduced to reduce the water hammer effect and improve the fiber interlacing strength.

[0020] In this invention, production efficiency and quality are improved through real-time feedback and multi-parameter coordination. Specifically, the fiber deposition amount is monitored in real time by a laser thickness gauge, and the slurry suction parameters are dynamically corrected by a PID algorithm. A collaborative optimization model is established for slurry temperature (35-45℃), pH value (6.8-7.5), and mold temperature (120-170℃) to match the best process combination.

[0021] In this invention, a complex mold is divided into independent control areas (main cavity area, edge reinforcement area, etc.) through mold zoning control, and a differentiated vacuum strategy (pressure difference within ±5%) is implemented for each zone; a detachable vacuum chamber design is adopted to adapt to the rapid switching of multiple product specifications.

[0022] When this utility model is used, its process flow includes: 1. Staged vacuum control process: Stage 1 (slurry spreading): Slurry concentration 1.0-1.5%, apply vacuum of -0.03~-0.05MPa for 3-5 seconds to form a uniform base layer; Phase 2 (Dehydration): The pressure is gradually increased to -0.10~-0.15MPa and lasts for 6-10 seconds to accelerate fiber densification; Phase 3 (Termination): After the thickness meets the standard, the vacuum level drops to -0.01MPa, triggering a termination signal.

[0023] 2. Pulsed vacuum application technology: High-pressure pulses (-0.12MPa / 0.5s) promote fiber densification, while low-pressure holding (-0.05MPa / 0.2s) releases internal stress. This cycle is repeated 3-5 times.

[0024] 3. Parameter matching process: Input mold structure parameters (aperture, curvature) → retrieve preset process library → real-time monitoring feedback → PID dynamic correction → output optimal slurry suction curve.

[0025] This invention achieves precise control of pulp suction volume by dynamically adjusting vacuum suction process parameters and optimizing mold structure. This method improves product uniformity, reduces energy consumption, and adapts to the production needs of products with multiple specifications. This invention has been successfully applied to pulp molding production in food packaging, electronic cushioning pads, and other fields. After implementation in an environmentally friendly products company in Guangdong, it reduced material loss of complex structure products by 22%, extended equipment maintenance cycle to more than 3000 hours, achieved thickness control accuracy of ±0.2mm, and reduced production cycle error to <5%.

[0026] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0027] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0028] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the connection structure of the solenoid valve assembly of this utility model; Figure 3 This is a schematic diagram of the partitioned suction mold of this utility model; Figure 4 This is a schematic diagram of the micropore array structure of this utility model.

[0029] Among them, 1-partitioned suction mold; 2-suction vacuum tube; 3-solenoid valve group; 4-data bus; 5-control module; 6-vacuum buffer tank; 7-pressure balance tube; 8-main vacuum pump; 9-micropore; 1-1-first suction mold; 1-2-second suction mold; 1-3-third suction mold; 3-1-first solenoid valve; 3-2-second solenoid valve; 3-3-third solenoid valve; 3-4-fourth solenoid valve. Detailed Implementation

[0030] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0031] according to Figures 1-4As shown, this utility model embodiment provides a pulp suction control device for pulp molding, including: a partitioned pulp suction mold 1, which is connected to a vacuum buffer tank 6 through a pulp suction vacuum tube 2, and the other end of the vacuum buffer tank 6 is connected to a main vacuum pump 8 through a pressure balance tube 7; the pulp suction vacuum tube 2 includes multiple tubes, each of which is equipped with a solenoid valve group 3, and each solenoid valve group 3 is connected to a control module 5 through a data bus 4.

[0032] In this utility model, there are a partitioned suction mold 1, a multi-channel vacuum system with independent solenoid valves, an intelligent controller and a vacuum buffer system, wherein the controller achieves molding thickness control by dynamically adjusting the vacuum parameters of each area.

[0033] When this pulp molding suction control device is in operation, the vacuum volume controller of the suction pipe controls multiple sets of solenoid valves, which in turn control the suction time and suction vacuum pressure of each suction vacuum tube 2 at each hole of the suction mold, thereby controlling the uniformity of suction in the suction mold. This pulp molding suction control device can also control the thickness requirements of different positions of the pulp molded product. Moreover, this device has low manufacturing cost, is easy to maintain, and has a simple structure.

[0034] By integrating the control module, the embedded controller incorporates multi-parameter optimization algorithms, supporting one-click import and adaptive learning of process parameters. Specifically, the embedded controller is a high-precision programmable vacuum pressure controller, specifically the VPC2021 series controller from Yiyang Company. This multifunctional and highly intelligent vacuum pressure measurement and process control instrument employs 24-bit data acquisition and artificial intelligence PID control technology. It can be connected to various types of vacuum pressure sensors (vacuum gauges), flow meters, temperature sensors, electric regulating valves, and heaters, enabling high-precision fixed-point and programmable control of parameters such as vacuum pressure, flow rate, and temperature. The PID control technology is existing technology and will not be elaborated further.

[0035] Optionally, depending on actual production, the human-machine interface can be selected to display real-time slurry suction curves, thickness distribution heat maps, and energy consumption statistics to further optimize the actual use function and effect of the control device.

[0036] Preferably, the partitioned suction mold 1 includes at least three suction molds, each connected to a vacuum buffer tank 6 via a suction vacuum tube 2. The number of solenoid valve assemblies 3 corresponds one-to-one with the number of suction molds. A laser thickness gauge (accuracy ±0.05mm) is arranged circumferentially around the mold, collecting thickness data every 10°; such as... Figure 1-3 As shown, the partitioned grout suction mold 1 includes a first grout suction mold 1-1, a second grout suction mold 1-2, and a third grout suction mold 1-3; each grout suction mold corresponds to a first solenoid valve 3-1, a second solenoid valve 3-2, and a fourth solenoid valve 3-4, respectively. Alternatively, the partitioned suction mold 1 includes a first suction mold 1-1, a second suction mold 1-2, a third suction mold 1-3, and a fourth suction mold ( Figure 3 The drawing number is not marked in the middle. Figure 3 The upper surface of the third suction mold 1-3); each suction mold corresponds to the first solenoid valve 3-1, the second solenoid valve 3-2, the third solenoid valve 3-3, and the fourth solenoid valve 3-4 respectively; each suction mold is connected to the vacuum buffer tank 6 through the suction vacuum tube 2 with the solenoid valve group 3; the main vacuum pump 8 transmits the vacuum negative pressure through the pressure balance tube 7 to each independent suction mold through the suction vacuum tube 2, thereby achieving the purpose of independently controlling each suction mold.

[0037] The vacuum pump unit adopts frequency conversion control, with a response time of ≤0.3 seconds and supports stepless adjustment from 0 to -0.15MPa. Preferably, the solenoid valve assembly 3 is a three-way solenoid valve, with one end connected to the slurry suction mold via the slurry suction vacuum pipe 2, the other end connected to the vacuum buffer tank 6 via the slurry suction vacuum pipe 2, and the third end connected to the forward and reverse blowing pipes. In this design, the solenoid valve assembly 3 has a response time of <50ms and supports bidirectional control of positive and negative pressure.

[0038] Preferably, the vacuum tube 2 is a transparent PVC pipe with an optical fiber flow rate sensor installed on its inner wall; the output end of the optical fiber flow rate sensor is electrically connected to the control module 5.

[0039] Multiple laser thickness gauges are evenly distributed on the circumferential inner wall of the partitioned suction mold 1; each laser thickness gauge is electrically connected to the control module 5 via wires.

[0040] Preferably, the partitioned suction mold 1 consists of at least 3-5 suction molds, each suction mold being an independent vacuum chamber, and the cavity of each independent vacuum chamber being independently connected to the vacuum buffer tank 6 via a solenoid valve.

[0041] Each independent vacuum chamber is an independently controlled region, which includes the main cavity region and the edge reinforcement region; the vacuum level of the main cavity region and the edge reinforcement region are different.

[0042] The reinforcing rib area is provided with multiple micropore arrays 9, each micropore 9 having a diameter of 0.8-1.2mm.

[0043] The main cavity area includes multiple gradient holes, each with a diameter that gradually decreases from large to small and is evenly distributed. The diameter of each gradient hole is 1.5-2.5mm.

[0044] In this utility model, the partitioned suction mold 1: suctions slurry in different areas by means of a combined mold or compartment. The surface of the mold is provided with a group of adsorption holes distributed according to the height gradient. The pore density increases exponentially with the height of the mold, wherein the density gradient coefficient α = 0.15-0.35.

[0045] Multi-channel vacuum system: includes at least 3 independently controlled suction vacuum tubes 2, each tube is equipped with a high-speed response solenoid valve, the response time of the solenoid valve is <50ms.

[0046] Intelligent controller: It integrates a PID control algorithm and connects to each solenoid valve via a data cable to adjust the vacuum pressure and adsorption time in real time. The adjustment accuracy of the vacuum pressure is ±0.5kPa and the adjustment accuracy of the adsorption time is ±0.1s.

[0047] Vacuum buffer tank 6: It is equipped with a pressure balance chamber and a piezoelectric pressure sensor.

[0048] This invention solves the problem of uncontrollable slurry absorption by dynamic vacuum regulation, coordinated optimization of process parameters and innovative mold structure, achieving a product thickness deviation of ≤±3%, a 30% improvement in the stability of wet blank moisture content, a 15-30% reduction in unit energy consumption, and a more than 50% extension of mold life; it also supports high-precision molding of complex geometric molds (such as multi-curved surfaces and reinforced rib structures).

[0049] In one embodiment, when producing irregularly shaped packaging products with a height difference > 300 mm: The mold is divided into three control areas: top, waist, and bottom. Initial parameters: Top vacuum pressure -85 kPa, adsorption time 3.2 s; Waist -78 kPa / 4.5 s; Bottom -72 kPa / 5.8 s; The controller automatically corrects the pressure parameters (correction range ≤15%) by providing real-time feedback of thickness data through a laser thickness gauge. The yield rate increased from 78% to 93% during the production cycle, and the thickness deviation was controlled within ±0.15mm.

[0050] In this invention, the fiber interlacing strength is improved through dynamic vacuum gradient control technology. Specifically, based on the fiber concentration and mold structure characteristics, the vacuum level is adjusted in stages (low vacuum slurry laying in the early stage and high pressure dewatering in the later stage) to avoid fiber breakage. A pulsed vacuum waveform (0.5s high pressure / 0.2s low pressure alternation) is introduced to reduce the water hammer effect and improve the fiber interlacing strength.

[0051] In this invention, production efficiency and quality are improved through real-time feedback and multi-parameter coordination. Specifically, the fiber deposition amount is monitored in real time by a laser thickness gauge, and the slurry suction parameters are dynamically corrected by a PID algorithm. A collaborative optimization model is established for slurry temperature (35-45℃), pH value (6.8-7.5), and mold temperature (120-170℃) to match the best process combination.

[0052] In this invention, a complex mold is divided into independent control areas (main cavity area, edge reinforcement area, etc.) through mold zoning control, and a differentiated vacuum strategy (pressure difference within ±5%) is implemented for each zone; a detachable vacuum chamber design is adopted to adapt to the rapid switching of multiple product specifications.

[0053] When this utility model is used, its process flow includes: 1. Staged vacuum control process: Stage 1 (slurry spreading): Slurry concentration 1.0-1.5%, apply vacuum of -0.03~-0.05MPa for 3-5 seconds to form a uniform base layer; Phase 2 (Dehydration): The pressure is gradually increased to -0.10~-0.15MPa and lasts for 6-10 seconds to accelerate fiber densification; Phase 3 (Termination): After the thickness meets the standard, the vacuum level drops to -0.01MPa, triggering the termination signal.

[0054] 2. Pulsed vacuum application technology: High-pressure pulses (-0.12MPa / 0.5s) promote fiber densification, while low-pressure holding (-0.05MPa / 0.2s) releases internal stress. This cycle is repeated 3-5 times.

[0055] 3. Parameter matching process: Input mold structure parameters (aperture, curvature) → retrieve preset process library → real-time monitoring feedback → PID dynamic correction → output optimal slurry suction curve.

[0056] By integrating the control module 5, the embedded controller integrates a multi-parameter optimization algorithm, supports one-click import of process parameters and adaptive learning; the human-machine interface displays real-time suction curves, thickness distribution heat maps and energy consumption statistics.

[0057] This invention achieves precise control of pulp suction volume by dynamically adjusting vacuum suction process parameters and optimizing mold structure. This method improves product uniformity, reduces energy consumption, and adapts to the production needs of products with multiple specifications. This invention has been successfully applied to pulp molding production in food packaging, electronic cushioning pads, and other fields. After implementation in an environmentally friendly products company in Guangdong, it reduced material loss of complex structure products by 22%, extended equipment maintenance cycle to more than 3,000 hours, achieved thickness control accuracy of ±0.2mm, and reduced production cycle error to <5%.

[0058] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A pulp suction control device for pulp molding, characterized in that, include: The partitioned suction mold is connected to a vacuum buffer tank via a suction vacuum pipe, and the other end of the vacuum buffer tank is connected to the main vacuum pump via a pressure balance pipe. The vacuum tubes for slurry suction consist of multiple tubes, each equipped with a solenoid valve assembly. Each solenoid valve assembly is connected to the control module via a data bus.

2. The pulp suction control device for pulp molding as described in claim 1, characterized in that, The partitioned suction mold includes at least three suction molds, each of which is connected to a vacuum buffer tank via a suction vacuum tube.

3. The pulp suction control device for pulp molding as described in claim 2, characterized in that, The number of solenoid valve assemblies corresponds one-to-one with the number of suction molds.

4. The pulp suction control device for pulp molding as described in claim 1, characterized in that, The solenoid valve assembly is a three-way solenoid valve, with one end connected to the slurry suction mold through the slurry suction vacuum pipe, the other end connected to the vacuum buffer tank through the slurry suction vacuum pipe, and the other end connected to the forward and reverse blowing pipes.

5. The pulp suction control device for pulp molding as described in claim 1, characterized in that, The vacuum suction tube is a transparent PVC pipe with an optical fiber flow rate sensor installed on its inner wall; the output end of the optical fiber flow rate sensor is electrically connected to the control module.

6. The pulp suction control device for pulp molding as described in claim 1, characterized in that, The partitioned suction mold consists of at least 3-5 suction molds, each with an independent vacuum chamber. The cavity of each independent vacuum chamber is independently connected to the vacuum buffer tank via a solenoid valve.

7. The pulp suction control device for pulp molding as described in claim 1, characterized in that, Multiple laser thickness gauges are evenly distributed on the circumferential inner wall of the partitioned suction mold; each laser thickness gauge is electrically connected to the control module via wires.

8. The pulp suction control device for pulp molding as described in claim 6, characterized in that, Each independent vacuum chamber is an independently controlled region, which includes the main cavity region and the edge reinforcement region; the vacuum level of the main cavity region and the edge reinforcement region are different.

9. The pulp suction control device for pulp molding as described in claim 8, characterized in that, The reinforcing rib area is provided with multiple micropore arrays, each micropore having a diameter of 0.8-1.2 mm.

10. The pulp suction control device for pulp molding as described in claim 8, characterized in that, The main cavity area includes multiple gradient holes, each with a diameter that gradually decreases from large to small and is evenly distributed. The diameter of each gradient hole is 1.5-2.5mm.

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