A continuous anti-overturning feeding and discharging device for flat material suitable for belt vacuum drying

Abstract

The present application relates to vacuum drying feed technology, and discloses a continuous anti-overturning feeding and discharging device for flat materials. The device establishes a pressure buffer gradient between normal pressure and vacuum through a multi-cavity rotary door, and realizes material pushing by using a one-way avoidance push rod. The device can ensure the posture of the flat material stable and not overturning during the whole feeding and discharging process while maintaining the constant pressure inside the vacuum drying chamber, and significantly improves the stability and reliability of continuous production.

Description

Technical Field

[0001] This invention relates to the field of vacuum drying equipment technology, and in particular to a continuous anti-tumble feeding and discharging device for flat materials used in belt vacuum drying, which is suitable for reliable feeding of flat materials while maintaining a stable vacuum environment inside the vacuum drying chamber. Background Technology

[0002] Vacuum drying technology can effectively preserve the nutrition and flavor of heat-sensitive agricultural products. It is a core process for the deep processing of flat materials such as sunflower heads and fruit and vegetable slices, and represents the mainstream development direction for improving the quality and efficiency of the agricultural product deep processing industry in the future. Continuous vacuum feeding and discharging is a necessary pre- and post-processing step in belt vacuum drying production. The operating performance of the feeding and discharging device directly determines the stability of the vacuum drying chamber, the drying quality of the materials, and the continuous operation efficiency of the production line.

[0003] Chinese patent number CN224057316U adopts a batch-type buffer feeding mode, but the continuity of feeding needs to be improved for the operation rhythm of continuous production lines.

[0004] Chinese patent CN223334023U discloses a vacuum feeding device, whose technical solution is mainly aimed at powders with good flowability. For flat solid materials such as sunflower discs and fruit and vegetable slices, the device lacks effective attitude control during the conveying process, and there is a possibility of jamming or overturning.

[0005] Chinese patent CN224086627U discloses a vacuum-feed powder mixing agitator. Powered by a motor, this device utilizes the interaction between a rotating drive block, an elastic reset rod, a material blocking block, and a raw material placement shell to achieve stepwise vacuum feeding, uniform mixing, and efficient blending of multi-component powder materials. However, compared to dedicated conveying structures for large-size, flat materials, this device has lower adaptability to various operating conditions, less compatibility with continuous production, and lacks material attitude control and anti-jamming protection structures, making it more prone to material breakage, overturning, and equipment jamming.

[0006] Chinese patent CN222647132U discloses a powder vacuum feeding system capable of preventing blockage. The core feeding method of this equipment is negative pressure vacuum suction, and the conveying pipeline is equipped with a rotating vertical rod with unblocking protrusions, achieving both closed vacuum feeding of ultrafine powder materials and blockage prevention and unblocking of the conveying pipeline. However, the feeding and discharging stages of this equipment are independent and lack a vacuum gradient stabilization structure, easily causing drastic fluctuations in the vacuum degree of the vacuum drying chamber. Furthermore, the material pushing mechanism, anti-tilting mechanism, and continuous feeding and discharging coordination system are completely missing, resulting in extremely low continuous operation efficiency of the production line. Therefore, developing a continuous anti-tilting feeding and discharging device for flat materials in belt vacuum drying, capable of conveying materials during pressure differential transitions, is particularly important. Summary of the Invention

[0007] This invention aims to overcome the shortcomings of existing technologies and provide a continuous anti-tumble feeding and discharging device for flat materials suitable for belt vacuum drying. Specifically addressing the industry pain points of flat materials being prone to tumbling, jamming, and causing pressure fluctuations in the vacuum chamber during vacuum transition, this device proposes a solution integrating pressure gradient buffering and unidirectional forced pushing.

[0008] The technical solution adopted by this invention to solve its technical problem is summarized as follows:

[0009] This device mainly consists of a vacuum drying chamber, a vacuum pump, an atmospheric pressure side feeding conveyor assembly, a vacuum side discharging conveyor assembly, a rotating door transition device, and a one-way flipping reciprocating push rod mechanism.

[0010] The rotating door transition device serves as a physical barrier and pressure buffer between the atmospheric pressure environment and the vacuum environment. Internally, a specific rotating body divides the circular chamber into multiple independent buffer chambers with pressures varying with the rotation angle. During operation, as the rotating body advances, the independent chamber containing the material moves from the atmospheric pressure inlet to the vacuum outlet. During this process, utilizing the principle of micro-pressure relief between the chambers, the pressure within the chamber decreases steadily in a stepwise manner, eventually approaching the pressure within the vacuum drying chamber before reaching the outlet. This design avoids direct exposure of the material to a large instantaneous pressure difference, fundamentally eliminating the potential hazards of material splashing, shape reversal, and drastic fluctuations in the vacuum level of the drying chamber caused by sudden pressure changes.

[0011] The unidirectional reciprocating push rod mechanism is responsible for the forced displacement control of materials. This mechanism is located on the side of the conveyor belt, and its pushing end employs a special unidirectional force-bearing structure. When the push rod pushes the material forward, the pushing surface remains rigidly vertical, ensuring that flat materials are pushed into the revolving door cavity with uniform force and a stable posture. When the push rod returns to its origin after pushing, if the pushing surface encounters subsequent materials or conveyor belt accessories that obstruct it, the pushing surface can automatically flip upward to physically avoid the obstacle. After overcoming the obstacle, it relies on its own weight or a reset component to restore its pushing posture. This process realizes a continuous operating logic of "rigid forward pushing and flexible backward avoidance," effectively preventing flat materials from being carried back or jammed during the push rod's return stroke.

[0012] Furthermore, in order to cooperate with the push rod's avoidance logic, this device is equipped with a guide separation structure at a specific position on the conveyor belt, which works in conjunction with the avoidance notch on the push rod's pushing surface to ensure that the push rod can accurately insert into the tail end of the material each time it falls back without interfering with the conveyor belt's sidewall.

[0013] Furthermore, the entire system is controlled by a timing control system. This system coordinates the feeding rhythm of the feed conveyor belt, the stepping angle of the rotating door, and the extension and retraction frequency of the push rods, ensuring that the push rods only perform the pushing action when the independent cavity of the rotating door is precisely aligned with the conveyor belt outlet, thereby achieving a seamless connection between material conveying and vacuum sealing processes.

[0014] The beneficial effects of this invention are as follows:

[0015] Excellent vacuum maintenance: The multi-chamber rotating structure forms a decreasing pressure gradient, replacing the traditional gate hard seal. The pressure fluctuation in the drying chamber is minimal throughout the feeding and discharging process, reducing the frequent start-stop load of the vacuum pump.

[0016] The anti-tumble effect is significant: flat materials always maintain a horizontal posture and move with the rotating door, and the push rod pushes in a straight line with surface contact, so the materials do not roll before and after entering the drying chamber conveyor belt, ensuring the uniformity of subsequent drying processes.

[0017] Strong continuous operation capability: The one-way avoidance push rod eliminates the risk of manual reset or material jamming and shutdown. Combined with intermittent stepping control logic, it can be perfectly integrated into continuous production lines. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall device of the present invention.

[0019] Figure 2 This is a schematic diagram of the overall material inlet and outlet of the present invention and a schematic diagram of the principle of pressure gradient change in the independent cavity of the rotating door transition device under different rotation angles.

[0020] Figure 3 This is a top view schematic diagram of the material feeding process of the present invention.

[0021] Figure 4 This is a schematic diagram of the push rod and push plate being lifted during the return stroke of the present invention.

[0022] Figure 5 This is a schematic diagram of the pusher plate of the present invention in three working positions (a-pushing material; b-lifting upon encountering material during return; c-lifting upon encountering a baffle during return).

[0023] In the diagram: 1-One-way reciprocating push rod mechanism; 2-Feed conveyor belt; 3-Discharge conveyor belt; 4-Feed rotary door transition device; 5-Discharge rotary door transition device; 6-Motor; 7-Vacuum drying chamber; 8-Vacuum pump; a-Push plate pushing material working position; b-Push plate returning to material working position; c-Push plate returning to conveyor belt baffle working position. 101-Push rod drive component; 102-Push rod; 103-Push baffle; 1031-Avoidance hole; 104-Square separation protrusion; 105-One-way flip connection structure; 201-Conveyor belt baffle; 401-Rotating cavity; 402-Arc-shaped rotating blade; 403-Impeller; 404-Self-lubricating material layer; 405-Elastic material layer; 601-Feed conveyor belt power motor; 602-Rotating door power motor. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0025] As shown in the schematic diagram on the homepage, this invention discloses a vacuum continuous feeding and discharging device with a reciprocating push rod and a rotating door transition seal. It mainly includes a unidirectional flip-type reciprocating push rod mechanism (1), a feeding conveyor belt (2), a feeding rotating door transition device (4), a discharging rotating door transition device (5), and a vacuum drying chamber (7). A receiving conveyor belt is fixedly installed inside the vacuum drying chamber (7); the feeding conveyor belt is arranged on the atmospheric pressure side above the vacuum drying chamber (7), and a square separation protrusion (104) and a horizontally arranged unidirectional flip-type reciprocating push rod mechanism (1) are fixed on the conveyor belt. The pushing end of the reciprocating push rod mechanism is precisely aligned with the feeding end of the feeding rotating door transition device (4).

[0026] like Figure 2This is a schematic diagram of the overall material feeding and discharging process of the device. The discharge end of the feeding rotary gate transition device (4) is connected to the vacuum drying chamber (7) via a sealed structure; the discharge rotary gate transition device (5) is located at the bottom of the vacuum drying chamber, with its feeding end connected to the bottom of the vacuum drying chamber (7) via a sealed structure, and its discharge end directly exposed to atmospheric pressure. Both types of rotary gate transition devices are located in an atmospheric pressure environment externally, while their internal structures are evenly divided into six large-capacity independent cavities by six arc-shaped rotating blades. The device's power system consists of motors that can synchronously drive the feeding rotary gate transition device, the discharge rotary gate transition device (5), the receiving conveyor belt, and the feeding conveyor belt. It should be noted that this device is particularly suitable for continuous feeding and discharging of flat materials (such as sunflower discs) in vacuum drying. Its core is to use the vacuum pressure of the vacuum drying chamber to achieve a smooth change of the vacuum gradient inside the rotating door transition device. During operation, the feeding rotating door transition device (4) divides the rotating cavity (401) into six independent cavities through rotating blades (402). Each cavity changes its pressure environment in turn as the impeller (403) rotates intermittently. Specifically: First stage (0° position): When an independent cavity rotates to the horizontal feed port position (corresponding to the 0° position in the figure), the cavity is connected to the atmospheric pressure side, and the internal air pressure is normal pressure (1 atm). At this time, the one-way flipping reciprocating push rod mechanism (1) pushes the material into the cavity. Second stage (0°→60°): After the material enters, the rotating door rotates 60° step by step, and the cavity begins to leave the atmospheric pressure side. At this time, the cavity opening gradually closes, and the negative pressure of the vacuum drying chamber (7) acts on the cavity through the tiny gap (or the preset pressure relief channel) between the edge of the rotating blade (402) and the inner wall of the rotating cavity (401), and begins to slowly extract the air from the cavity. Third stage (60°→120°): The cavity continues to rotate to the 120° position. As the evacuation time increases, the air pressure in the cavity further decreases, experiencing gradients of approximately 0.7 atm, 0.5 atm, and 0.3 atm in sequence. Fourth stage (120°→180°): When the cavity continues to rotate to the 180° vertical discharge port position, the air pressure in the cavity has dropped to below approximately 0.1 atm, which is basically the same as the air pressure inside the vacuum drying chamber (7). At this time, the cavity opening faces downward, and the material falls steadily into the receiving conveyor belt inside the vacuum drying chamber (7) under the action of gravity. In the rotation range of 120° to 180°, the air pressure inside the cavity continues to decrease slowly and eventually stabilizes at the same level as the vacuum drying chamber, while the material posture remains unchanged.

[0027] It should be noted that during this rotational transition process, because the inner wall of the arc-shaped blade (402) is a smooth arc surface, and the cavity rotates horizontally with the rotating door, the flat material remains pressed against and lies flat on the bottom surface of the cavity under the influence of gravity. Therefore, during the 180-degree rotation from the horizontal feed port to the vertical discharge port, the material only undergoes positional translation and angular deflection with the cavity, while the orientation of its upper and lower surfaces remains unchanged, thus fundamentally eliminating the possibility of material flipping inside the transition cavity.

[0028] In this embodiment, the discharge rotary gate transition device (5) is completely identical to the above-mentioned feed rotary gate transition device (4) in terms of mechanical structure and sealing principle. It also includes a rotating cavity (401), an arc-shaped rotating blade (402), and a self-lubricating / elastic sealing layer. Both establish a pressure gradient through a multi-cavity structure to maintain a constant pressure inside the vacuum drying chamber (7).

[0029] The only difference between the discharge process and the feeding process is that the material flow direction is opposite to the direction of the pressure gradient. On the feeding side, the independent chamber rotates from the atmospheric pressure inlet to the vacuum outlet, and the chamber undergoes a depressurization process. On the discharge side, the independent chamber receives material from the vacuum inlet at the bottom of the vacuum drying chamber (7) and then rotates towards the atmospheric pressure outlet, and the chamber undergoes a repressurization process. During the discharge rotation, the flat material is still constrained by the smooth inner wall of the arc-shaped blade (402) and gravity, maintaining an upward orientation, and finally smoothly transitions to the discharge conveyor belt (3) in the external atmospheric pressure environment. The unidirectional flipping reciprocating push rod mechanism (1) can also be configured on the side of the discharge conveyor belt (3) to push the falling material away from the discharge port and prevent accumulation and jamming.

[0030] The pressure gradient transformation design avoids problems such as material splashing, morphological damage (such as sunflower disc flipping) and drastic fluctuations in vacuum caused by sudden pressure changes in traditional gate valves or simple rotary valves, ensuring the continuous stability of the vacuum environment inside the vacuum drying chamber (7).

[0031] like Figure 4 , Figure 5As shown, the one-way flipping reciprocating push rod mechanism (1) consists of a drive component (101), a push rod body (102), and a push baffle (103) fixed to the front end of the push rod body (102). The push baffle (103) is connected to the push rod body (102) through a one-way flipping connection structure (105), which keeps the push baffle in a rigid force state during the push rod's pushing stroke (a); and during the push rod's return stroke, if it is disturbed by material, it can be raised to a certain rotation angle α (b), and if it is disturbed by an external baffle, it can be raised to an angle β to avoid it (c). At the same time, the push baffle (103) adopts a planar structure and has an avoidance hole on its pushing side. When the push baffle with the avoidance hole is in place, it forms an avoidance fit with the square separation protrusion (104) on the feeding conveyor belt (2), which can eliminate the hidden danger of material adhering to the push baffle and causing the push rod's return stroke to be blocked. In this embodiment, the drive component (101) is preferably an electronic push rod, but a cylinder, hydraulic cylinder or lead screw mechanism may also be used.

[0032] Furthermore, the feeding rotary gate transition device (4) and the discharging rotary gate transition device (5) have the same structure, both including a rotating cavity (401), arc-shaped rotating blades (the blades are composed of radial straight plates and arc-shaped plates connected to them), high-temperature resistant elastic sealing material, and a power motor (601, 602). The rotating cavity is divided into six independent cavities by six arc-shaped rotating blades (a combination of straight plates and arc plates). The design of these arc-shaped blades can better adapt to the transportation of flat materials and effectively avoid material jamming or damage in the cavity. The power motor is driven by a motor control system, which can realize the intermittent rotation of the device to ensure accurate material delivery and transition sealing.

[0033] Working principle of this invention:

[0034] When using this device, the feeding conveyor belt holds the flattened material, the motor starts, and the entire device enters automatic operation mode. The vacuum pump runs continuously, providing overall vacuum pressure.

[0035] During the feeding process, the motor control system controls the power motor to precisely rotate an idle large-capacity independent cavity of the feeding rotary gate transition device to the predetermined working position (the opening of the rotary gate cavity is aligned and the conveyor belt baffle is just rotated to a horizontal position). At this time, the rotary gate device, the feeding conveyor belt and the receiving conveyor belt stop running.

[0036] The unidirectional reciprocating push rod mechanism is activated, and the electronic push rod drives the push rod body to move forward horizontally. The push baffle returns to its downward position, rigidly fitting the side of the sunflower disc and smoothly pushing it into the aligned independent cavity. This ensures that the material enters the cavity completely without deviation or damage. The clearance holes on the baffle allow airflow and reduce pushing resistance. The square separation protrusion cooperates with the clearance holes to assist the material in a smooth transition from the feed conveyor belt, further eliminating material adhesion to the push baffle. After pushing is completed, the rotating door and conveyor belt run synchronously, and the electronic push rod returns. If it encounters interference from subsequent material below during the return process, the push baffle lifts upward in one direction to avoid it, and then automatically resets.

Claims

1. A continuous anti-tumble feeding and discharging device for flat materials suitable for belt vacuum drying, characterized in that, include: Vacuum drying chamber (7); vacuum pump (8) connected to the vacuum drying chamber (7); feed conveyor belt (2) and discharge conveyor belt (3); one-way reciprocating push rod mechanism (1); feed rotary door transition device (4) and discharge rotary door transition device (5); the feed conveyor belt (2) and the feed rotary door transition device (4) are located on the atmospheric pressure side of the feed end of the vacuum drying chamber (7), and the discharge conveyor belt (3) and the discharge rotary door transition device (5) are located on the vacuum side of the bottom of the vacuum drying chamber (7); the one-way reciprocating push rod mechanism (1) is located on the side of the feed conveyor belt (2) or the discharge conveyor belt (3); the feed rotary door transition device (4) and the discharge rotary gate transition device (5) both include a rotating cavity (401) and a plurality of rotating blades (402) evenly distributed in the rotating cavity. The plurality of rotating blades (402) divide the rotating cavity (401) into a plurality of independent cavities. The edges of the rotating blades (402) are provided with a self-lubricating material layer (404) and an elastic material layer (405) that seal with the inner wall of the rotating cavity. The feed port of the feed rotary gate transition device (4) is set to allow the material to enter under the assistance of gravity, and its discharge port is set to allow the material to fall out under the action of gravity. The feed port is located in the horizontal direction, and the discharge port is located vertically below and communicates with the vacuum drying chamber (7).

2. The continuous anti-tumble feeding and discharging device for flat materials suitable for belt vacuum drying according to claim 1, characterized in that, The one-way flipping reciprocating push rod mechanism (1) includes a drive component (101), a push rod (102), and a push baffle (103). The push baffle (103) is connected to the front end of the push rod (102) through a one-way flipping connection structure (105). The push baffle (103) maintains a rigid force state during the pushing stroke and can flip upward relative to the push rod (102) to avoid it during the return stroke.

3. A continuous anti-tumble feeding and discharging device for flat materials suitable for belt vacuum drying according to claim 2, characterized in that, The feeding conveyor belt (2) and the discharging conveyor belt (3) are also provided with conveyor belt baffles (201) and square separation protrusions (104) located on the side of the conveyor belt baffles (201) and close to the revolving door. The lower side of the push baffle (103) is provided with a clearance hole that is adapted to the square separation protrusions (104). The size and position of the clearance hole are set such that when the push baffle (103) is in the lowest working position, the square separation protrusions (104) are at least partially accommodated in the clearance hole. The two cooperate to ensure that there is a gap for the push baffle (103) to reset between the next conveyor belt baffle (201) and the material, ensuring smooth return while pushing the next material. The upper edge of the push baffle (103) is not lower than the upper edge of the conveyor belt baffle (201).

4. A continuous anti-tumble feeding and discharging device for flat materials suitable for belt vacuum drying according to claim 1, characterized in that, The rotating blades (402) are arranged horizontally and are arc-shaped, with no fewer than four blades, which uniformly divide the rotating cavity (401) into no fewer than four independent cavities. A sealing structure is provided between the edge of the rotating blades (402) and the inner wall of the rotating cavity (401). The sealing structure includes a self-lubricating material layer (404) and an elastic material layer (405) fixed to the edge of the rotating blades, so that a decreasing air pressure gradient is formed between adjacent independent cavities during rotation, so as to ensure continuous feeding without damaging the vacuum in the drying chamber. The horizontal arrangement of the rotating blades (402) and the rotating cavity (401) ensures that one side of the material is always facing upwards and does not flip over when feeding or discharging.

5. A continuous anti-tumble feeding and discharging device for flat materials suitable for belt vacuum drying according to claim 1, characterized in that, It also includes a motor control system, wherein the motor control circuit is electrically connected to the power motor (601) of the feeding conveyor belt (2), the power motor of the discharging conveyor belt (3), the power motor (602) of the feeding rotary gate transition device (4) and the power motor of the discharging rotary gate transition device (5) respectively, so as to control the intermittent stepping operation of each motor and coordinate with the pushing action timing of the unidirectional flip-type reciprocating push rod mechanism (1).

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