Continuous peeling device for pretreatment of berries before vacuum freeze-drying

Abstract

This utility model relates to a continuous peeling device for pretreatment of berries before vacuum freeze-drying, belonging to the technical field of berry processing equipment. This device aims to solve the technical problems of berries having dense outer skins covered with a waxy layer, resulting in low efficiency and excessively long vacuum freeze-drying time, and easily causing internal pressure increases leading to collapse and shrinkage. The solution includes: a material conveying system with a grooved first conveyor belt; a quick-freezing system with a quick-freezing chamber mounted on the conveyor belt and equipped with a refrigeration mechanism for freezing the berries; and an automatic peeling system mounted downstream of the quick-freezing system, including a motor, a transmission mechanism, and two opposing forward and reverse drive shafts driven by the motor. The two shafts are respectively equipped with opposing forward and reverse blades, which shear the quick-frozen berry skin in the grooves through opposite rotation. This device is mainly used for automated pretreatment of berries such as blueberries to improve the rate and quality of subsequent vacuum freeze-drying.

Description

Technical Field

[0001] This utility model relates to the field of berry processing equipment. More specifically, this utility model relates to a continuous peeling device for pretreatment of berries before vacuum freeze-drying. Background Technology

[0002] In recent years, vacuum freeze-drying has gained market popularity due to its ability to preserve the color and appearance of natural berries such as blueberries, as well as retain active ingredients like anthocyanins. Vacuum freeze-drying has become a major processing technique for berries like blueberries. However, the dense structure of the natural blueberry skin, along with a waxy layer, results in extremely low water permeability, significantly reducing freeze-drying efficiency. This often leads to freeze-drying times exceeding 24 hours in actual production. Furthermore, the outer skin prevents water vapor from escaping during the sublimation stage, causing increased internal pressure. This increased pressure leads to the melting of the internal tissues, causing the freeze-dried blueberries to collapse and form a heterogeneous, macroporous structure, resulting in a severely shrunken appearance. Summary of the Invention

[0003] One object of this invention is to solve at least the problems described above and to provide at least the advantages that will be explained later.

[0004] To achieve these objectives and other advantages according to the present invention, a continuous peeling apparatus for pretreatment of berries before vacuum freeze-drying is provided, comprising: A material conveying system includes a first conveyor belt, which is composed of alternating material holding areas and connecting areas, wherein the material holding area is provided with grooves for holding materials. A quick-freezing system includes a quick-freezing chamber. Each of the two opposite walls of the quick-freezing chamber has an opening for a first conveyor belt to pass through. The quick-freezing chamber is mounted on the upper layer of the first conveyor belt. The upper layer of the first conveyor belt enters the quick-freezing chamber through one opening and exits the quick-freezing chamber through the other opening. A refrigeration mechanism is installed inside the quick-freezing chamber. An automatic peeling system is installed above the upper layer of the first conveyor belt and downstream of the quick-freezing system. The automatic peeling system includes a motor and a transmission mechanism connected to the motor. The output end of the transmission mechanism includes a forward transmission shaft and a reverse transmission shaft with opposite directions. The reverse transmission shaft is hollow inside and open at both ends. The forward transmission shaft coaxially passes through the center of the reverse transmission shaft. Both the forward and reverse transmission shafts are perpendicular to the upper layer of the first conveyor belt. A plurality of forward-rotating blades are evenly arranged circumferentially at the lower end of the forward transmission shaft, and a plurality of reverse-rotating blades are evenly arranged circumferentially at the lower end of the reverse transmission shaft. The cutting edges of the forward-rotating blades and the reverse-rotating blades are opposite to each other to cut the surface of the material in the groove.

[0005] Preferably, the automatic peeling system further includes a telescopic mechanism disposed above the transmission mechanism, the output rod of the telescopic mechanism being perpendicular to the first conveyor belt, and the transmission mechanism being disposed on the output rod of the telescopic mechanism.

[0006] Preferably, each material holding area is provided with several grooves, and the grooves are distributed in a matrix. The transmission mechanism is provided with two rows of output end groups in the width direction of the first conveyor belt. The two rows of output end groups are respectively positioned for two rows of grooves in the groove matrix. Each row of output end groups has one output end arranged with a groove spaced apart, and the positions of each output end in one row of output end groups are staggered from those in the other row of output end groups.

[0007] Preferably, the transmission mechanism includes a primary transmission mechanism and a secondary transmission mechanism; The primary transmission mechanism includes two first transmission shafts distributed along the width direction of the first conveyor belt. A driving gear is provided on the output shaft of the motor. A first driven gear is provided at one end of each of the two first transmission shafts. The two first driven gears are located on both sides of the driving gear and mesh with the driving gear. The two first transmission shafts correspond to two rows of output end groups. Each first transmission shaft is provided with a number of worm gears corresponding to the number of output ends in the corresponding output end group. Each worm gear meshes with a worm perpendicular to the first conveyor belt for transmitting power to the output end. The secondary transmission mechanism includes a second driven gear located at the lower end of the worm, third driven gears meshing on both sides of the second driven gear, a fourth driven gear coaxially connected below the third driven gear, a fifth driven gear coaxially arranged on the reverse transmission shaft, the fourth driven gear meshing with the fifth driven gear, and another third driven gear coaxially arranged on the forward transmission shaft.

[0008] Preferably, the secondary transmission mechanism further includes a housing for accommodating the second driven gear to the fifth driven gear, the outer wall of the housing is connected to an infrared generator that emits signal light downwards, and an infrared receiver for receiving the signal light emitted by the infrared generator is provided between the upper and lower belts of the first conveyor belt. Each connecting section of the first conveyor belt has a window at its front end that allows the signal light to pass through; The motor is a variable frequency motor, which is communicatively connected to the infrared receiver. It is used to increase the rotation speed within a preset time after the infrared receiver receives the signal light, so that the forward and reverse blades can throw off the fruit peel.

[0009] Preferably, the refrigeration mechanism includes: A cooling air outlet duct extends through the top of the rapid cooling chamber to the top of the upper belt of the transmission belt; A return air duct extends through the bottom of the rapid cooling chamber to below the upper belt of the transmission belt. The opening of the quick-freezing compartment is also equipped with a windproof curtain made of flexible material.

[0010] Preferably, the cooling air outlet duct is equipped with an air volume regulating valve.

[0011] Preferably, it also includes: The material feeding system includes a second conveyor belt, which is positioned above the head end of the first conveyor belt; The post-peeling material collection system includes a third conveyor belt located below the end of the first conveyor belt.

[0012] Preferably, the first conveyor belt has a downward-sloping head end, and a material recycling system is provided below the head end of the first conveyor belt, the material recycling system including a fourth conveyor belt.

[0013] This invention offers at least the following advantages: The designed rotary blade peeler enables automatic pre-peeling of blueberries, with the number and depth of peeling points adjustable according to actual conditions. These peeled portions serve as areas for the outward diffusion of internal moisture during vacuum freeze-drying. This solves the problem of tissue collapse during existing blueberry vacuum freeze-drying techniques, achieving rapid pre-freezing and peeling of blueberries in a unified pre-treatment process with automatic collection.

[0014] Other advantages, objectives and features of this invention will be partly apparent from the following description, and partly understood by those skilled in the art through study and practice of this invention. Attached Figure Description

[0015] Figure 1 This is a side view of the continuous peeling device of this utility model; Figure 2 This is a top view of the primary transmission mechanism of this utility model. Figure 3 This is a side view of the secondary transmission mechanism described in this utility model; Figure 4 This is a schematic diagram illustrating the operation of the forward-rotating blade and the reverse-rotating blade described in this utility model; Figure 5 This is a side view of the material conveying system of the present invention. Figure 6 This is a top view of the structure of the first conveyor belt of this utility model; Figure 7 This is a side view of the material feeding system and material recovery system described in this utility model; Figure 8 This is a side view of the material collection system after peeling as described in this utility model; Figure 9 This is a side view of the quick-freezing system described in this utility model; Figure 10 A schematic diagram showing the appearance and interior of blueberries after direct vacuum freeze-drying. Figure 11 A schematic diagram showing the appearance of blueberries after they have been processed by the continuous peeling device and then subjected to vacuum freeze-drying. Figure 12 This is an internal schematic diagram of blueberry fruit after it has been processed by the continuous peeling device and then subjected to vacuum freeze-drying.

[0016] Among them, there are automatic peeling system-1, material conveying system-2, quick freezing system-3, material feeding system-4, material recycling system-5, and peeled material collection system-6; Hydraulic cylinder-11, variable frequency motor-12, first drive shaft-13, drive gear-14, first driven gear-15, worm gear-16, worm-17, second driven gear-18, third driven gear-19, fourth driven gear-110, fifth driven gear-111, forward drive shaft-112, reverse drive shaft-113, forward rotating blade-114, reverse rotating blade-115, infrared generator-116, infrared receiver-117; First conveyor belt-21, equipment support-22, front drive roller-23, rear drive roller-24, pallet-25, vibrating table-26, groove-27, window-28, corner roller-29; Quick-freezing compartment-31, refrigeration air outlet duct-32, return air duct-33, wind deflector-34, air volume regulating valve-35. Detailed Implementation

[0017] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0018] It should be noted that in the description of this utility model, the terms "horizontal", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0019] like Figures 1-12As shown, this utility model relates to a continuous peeling device for pretreatment of berries before vacuum freeze-drying. This device is mainly used in berry processing to freeze and peel berries before vacuum freeze-drying, thereby improving drying effect and product quality. The structure, usage process, and technical effects of the device will be described in detail below. The continuous peeling device includes: The material conveying system 2 includes a first conveyor belt 21, which is composed of an alternating material holding area and a connecting area. The material holding area is provided with a groove 27 for holding materials. The quick-freezing system 3 includes a quick-freezing chamber 31. Each of the two opposite walls of the quick-freezing chamber 31 has an opening for the first conveyor belt 21 to pass through. The quick-freezing chamber 31 is mounted on the upper part of the first conveyor belt 21. The upper part of the first conveyor belt 21 enters the quick-freezing chamber 31 through one opening and exits the quick-freezing chamber 31 through the other opening. A refrigeration mechanism is provided inside the quick-freezing chamber 31. An automatic peeling system 1 is mounted above the upper layer of the first conveyor belt and located downstream of the quick-freezing system. The automatic peeling system 1 includes a motor and a transmission mechanism connected to the motor. The output end of the transmission mechanism includes a forward transmission shaft 112 and a reverse transmission shaft 113 with opposite directions of rotation. The reverse transmission shaft 113 is hollow inside and open at both ends. The forward transmission shaft 112 coaxially passes through the center of the reverse transmission shaft 113. Both the forward transmission shaft 112 and the reverse transmission shaft 113 are perpendicular to the upper layer of the first conveyor belt. A plurality of forward-rotating blades 114 are evenly arranged circumferentially at the lower end of the forward transmission shaft 112, and a plurality of reverse-rotating blades 115 are evenly arranged circumferentially at the lower end of the reverse transmission shaft. The cutting edges of the forward-rotating blades 114 and the reverse-rotating blades 115 are opposite to each other to cut the surface of the material in the groove.

[0020] Specifically, in addition to the first conveyor belt 21, the material conveying system 2 also includes a necessary equipment support 22, left and right side plates mounted on the equipment support 22 and located outside the left and right sides of the first conveyor belt 21, a front drive roller 23 disposed between the front ends of the left and right side plates, a rear drive roller 24 disposed between the rear ends of the left and right side plates, and a motor for driving the front drive roller 23 or the rear drive roller 24 to rotate. The first conveyor belt 21 is wound around the front drive roller 23 and the rear drive roller 24.

[0021] More preferably, a support plate 25 connected between the upper and lower belts of the first conveyor belt 21 can be provided at a position between the left and right side plates. A bracket for supporting the upper belt and a vibration table 26 for micro-vibrating the upper belt of the first conveyor belt 21 can be provided on the support plate 25.

[0022] The first conveyor belt 21 includes at least one horizontal conveying section to facilitate the arrangement of the quick-freezing system 3 and the automatic peeling system 1.

[0023] The first conveyor belt 21 is composed of alternating material receiving areas and connecting areas. The material receiving area has grooves 27 for holding materials such as berries. The design of the grooves 27 prevents materials from rolling or falling during conveying, ensuring stable material transport. The connecting areas connect the various receiving areas, ensuring continuous operation of the conveyor belt. For example, the grooves 27 can be arranged in a rectangular array, with each groove 27 corresponding to one berry, so that each berry can be precisely positioned and processed during conveying.

[0024] The quick-freezing chamber 31 is equipped with a refrigeration mechanism. As the berries pass through the quick-freezing chamber 31 with the conveyor belt, the refrigeration mechanism rapidly freezes the berries, controlling the temperature to drop to approximately -1 to -10°C. The water in the berries forms ice crystals, while the unfrozen areas approach or enter a vitrified state. However, the whole fruit is not completely frozen, creating favorable conditions for subsequent peeling. This step enhances the rigidity of the berries, reducing mechanical damage during subsequent conveying and material transfer, and helps maintain the integrity of the pulp during peeling, minimizing juice loss.

[0025] An automatic peeling system 1 is mounted above the upper layer of the first conveyor belt and downstream of the quick-freezing system, responsible for peeling the quick-frozen berries. The system includes a motor and a transmission mechanism connected to it. The output end of the transmission mechanism has a unique structure: it includes a reverse drive shaft 113 and a forward drive shaft 112, which rotate in opposite directions. The reverse drive shaft 113 is hollow inside and open at both ends, while the forward drive shaft 112 passes coaxially through the central hole of the reverse drive shaft 113. Both drive shafts are mounted perpendicular to the plane of the conveyor belt. At the lower end of the forward drive shaft 112, multiple forward-rotating blades 114 are evenly mounted circumferentially; at the lower end of the reverse drive shaft 113, multiple reverse-rotating blades 115 are also evenly mounted circumferentially. The cutting edges of these blades are arranged opposite each other, forming a shearing structure similar to scissors.

[0026] As the berries move along the groove to the peeling station, the forward-rotating blade 114 and the reverse-rotating blade 115 rotate in opposite directions driven by a motor, using the relative motion between the blades to shear the berry skin. Because the blades are evenly distributed circumferentially, they can contact the peel from two directions, achieving a fast and uniform peeling effect. The combination of forward and reverse rotating blades not only improves peeling efficiency but also avoids problems such as tearing of the pulp or peel residue that may occur with unidirectional rotation.

[0027] The entire process of the device is as follows: berries are placed in the groove of the first conveyor belt and enter the quick-freezing chamber for freezing; then, the conveyor belt sends the berries to the bottom of the automatic peeling system 1, where the forward and reverse blades 115 rotate in coordination to precisely cut the berry skin; the peeled berries continue to be transported out by the conveyor belt, received by the collection system, and enter the subsequent vacuum freeze-drying process.

[0028] The continuous peeling device offers significant technological advantages. Firstly, it automates and continuously peels berries, greatly improving production efficiency and making it suitable for large-scale processing. Secondly, the process of quick-freezing followed by peeling effectively reduces damage to the pulp during peeling, preserving the integrity and nutritional components of the berries. Thirdly, targeting the dense outer skin and thick waxy layer of berries, the device employs a shearing peeling method, effectively breaking down the epidermal barrier. This facilitates water sublimation during subsequent freeze-drying, shortens freeze-drying time, and avoids fruit collapse and shrinkage caused by increased internal pressure, ultimately improving the quality of the freeze-dried berries.

[0029] Furthermore, the automatic peeling system 1 also includes a telescopic mechanism disposed above the transmission mechanism, the output rod of the telescopic mechanism being perpendicular to the first conveyor belt, and the transmission mechanism being disposed on the output rod of the telescopic mechanism.

[0030] Specifically, the telescopic mechanism can be fixed to a truss spanning the first conveyor belt. The telescopic mechanism can be implemented using a linear drive device such as an electric actuator, hydraulic cylinder 11, or pneumatic cylinder. Its core function is to provide precise vertical displacement control for the peeling unit. For example, when processing different varieties or sizes of berries, such as blueberries and raspberries, the individual sizes differ. By controlling the extension or retraction of the output rod of the telescopic mechanism, the height of the forward drive shaft 112, the reverse drive shaft 113, and all the blades mounted on them from the conveyor belt groove can be adjusted as a whole, thereby ensuring that the blades can contact the berry skin at the most suitable cutting depth.

[0031] In addition, when multiple automatic peeling systems 1 are set on the moving path of the first conveyor belt, the height of all the blades in the automatic peeling system 1 below from the groove of the conveyor belt can be controlled by the telescopic mechanism. One or more automatic peeling systems 1 can be selected to participate in the peeling work. With the slight vibration of the vibration table on the first conveyor belt, the berries are tumbled, so that one or more pieces of skin can be removed from the surface of the berries.

[0032] The introduction of a telescopic mechanism brings several beneficial effects. First, it greatly enhances the adaptability and flexibility of the device, allowing the same machine to process berries of different sizes through simple parameter adjustments, thus broadening its application range. Second, precise height control ensures that the blade cuts at a constant optimal depth, avoiding damage to the pulp from excessive cutting and preventing peel residue from insufficient cutting, thereby significantly improving the consistency of peeling operations and product quality. Finally, this height-adjustable design allows the peeling unit to be moved to a safe height during off-peak hours or maintenance, facilitating blade cleaning, replacement, or equipment maintenance, improving operational safety and maintenance convenience.

[0033] Furthermore, each material holding area is provided with several grooves, which are distributed in a matrix. The transmission mechanism is provided with two rows of output end groups in the width direction of the first conveyor belt. The two rows of output end groups are respectively positioned for two rows of grooves in the groove matrix. Each row of output end groups has one output end arranged with a groove spaced apart, and the positions of each output end in one row of output end groups are staggered from those in the other row of output end groups.

[0034] This clarifies that each material receiving area is not equipped with a single groove, but rather with multiple grooves arranged in a regular matrix. For example, a receiving area can have five rows and twelve columns of grooves, totaling sixty grooves, allowing the area to hold sixty berries at a time. This design significantly improves the material capacity per transfer and overall processing efficiency.

[0035] Corresponding to the matrix distribution of the grooves, the output ends of the transmission mechanism responsible for driving the blades to perform the peeling action are also designed with a corresponding layout in the width direction of the first conveyor belt. For example, suppose a row of the groove matrix has twelve grooves, numbered 1 to 12. The output end group for that row might arrange the output ends above grooves 1, 3, 5, 7, 9, and 11, while skipping grooves 2, 4, 6, 8, 10, and 12. The output end group in the other row, which is staggered, will adopt a complementary arrangement strategy for the corresponding row of grooves, for example, arranging the output ends above grooves 2, 4, 6, 8, 10, and 12. In this way, from an overall top-down view, all output ends present a staggered arrangement in the width direction of the conveyor belt.

[0036] During operation, when the material receiving area carrying the matrix-arranged berries moves to the peeling station, the blades in the first row of output units peel the berries below them in odd-numbered positions, while the second row of output units simultaneously peels the berries below them in even-numbered positions. As the first conveyor belt advances, the berries in the grooves of all rows of the material receiving area have their skins removed. Afterward, the material receiving area moves out, passes through the connecting area, and then enters the next material receiving area, thus achieving continuous operation in a cyclical manner.

[0037] This arrangement, through the staggered layout of the output end groups, ensures that all berries in the receiving area are processed without omission in a single work cycle, guaranteeing 100% processing coverage and ensuring production efficiency. At the same time, the staggered layout provides more ample lateral installation and maintenance space for each output end and its transmission components, avoiding potential structural interference between adjacent units, which is beneficial for stable equipment operation and daily maintenance.

[0038] Furthermore, the transmission mechanism includes a primary transmission mechanism and a secondary transmission mechanism; The primary transmission mechanism includes two first transmission shafts 13 distributed along the width direction of the first conveyor belt. A drive gear 14 is provided on the output shaft of the motor. A first driven gear 15 is provided at one end of each of the two first transmission shafts 13. The two first driven gears 15 are located on both sides of the drive gear 14 and mesh with the drive gear 14. The two first transmission shafts 13 correspond to two rows of output end groups. Each first transmission shaft 13 is provided with a number of worm gears 16 corresponding to the number of output ends in the corresponding output end group. Each worm gear 16 meshes with a worm 17 perpendicular to the first conveyor belt for transmitting power to the output end. The secondary transmission mechanism includes a second driven gear 18 disposed at the lower end of the worm gear 17, with third driven gears 19 meshing on both sides of the second driven gear 18, a fourth driven gear 110 coaxially connected below the third driven gear 19, a fifth driven gear 111 coaxially disposed on the reverse transmission shaft 113, the fourth driven gear 110 meshing with the fifth driven gear 111, and another third driven gear 19 coaxially disposed on the forward transmission shaft 112.

[0039] Specifically, the primary transmission mechanism is mainly responsible for the initial distribution of power and the conversion of direction. When the motor starts, the driving gear 14 simultaneously drives two first driven gears 15, thereby causing the two first transmission shafts 13 to rotate at the same speed and direction. Each first transmission shaft 13 is also equipped with a number of worm gears 16 equal to the number of output ends in its corresponding row of output end groups. Each worm gear 16 meshes with a worm 17 mounted perpendicular to the plane of the first conveyor belt. In this way, the rotational motion of the first transmission shaft 13 is converted into the rotational motion of each worm 17 through the worm gear 16 and worm 17 pair, realizing the initial transmission of power to the lower secondary transmission mechanism and the conversion of spatial direction.

[0040] The secondary transmission mechanism is precisely mounted at the lower end of each worm 17. Its core function is to convert the single rotation of an input shaft (worm 17) into the opposite rotational motion of a pair of output shafts (forward transmission shaft 112 and reverse transmission shaft 113). Specifically, a second driven gear 18 is fixedly mounted at the lower end of the worm 17. On both sides of this second driven gear 18, a third driven gear 19 is meshed. A fourth driven gear 110 is coaxially connected to the lower part of the third driven gear 19 on one side via a shaft system. A fifth driven gear 111 is coaxially fixedly mounted on the reverse transmission shaft 113, and this fifth driven gear 111 directly meshes with the aforementioned fourth driven gear 110. The third driven gear 19 on the other side is directly coaxially mounted to the upper end of the forward transmission shaft 112. Through the meshing relationship of this series of gears, the second driven gear 18 drives the two third driven gears 19 to rotate in the same direction, thereby causing the forward drive shaft 112 connected to it and the reverse drive shaft 113 driven by the fourth and fifth gear pairs to obtain opposite rotation directions, ultimately realizing the opposite shearing motion of the forward rotating blade 114 and the reverse rotating blade 115.

[0041] Furthermore, the secondary transmission mechanism also includes a housing for accommodating the second driven gear 18 to the fifth driven gear 111. An infrared generator 116 for emitting signal light downwards is connected to the outer wall of the housing. An infrared receiver 117 for receiving the signal light emitted by the infrared generator 116 is provided between the upper and lower belts of the first conveyor belt. Each connecting section of the first conveyor belt has a window 28 at its front end that allows the signal light to pass through; The motor is a variable frequency motor 12, which is communicatively connected to the infrared receiver 117. The motor is used to increase the rotation speed within a preset time after the infrared receiver 117 receives the signal light, so that the forward-rotating blade 114 and the reverse-rotating blade 115 can throw off the fruit peel.

[0042] The housing not only encloses the precision gear set but also serves to protect against dust and foreign objects. Similarly, a housing for enclosing the drive shaft and gear set is also provided in the primary transmission mechanism. The output rod of the telescopic mechanism is connected to the housing of the primary transmission mechanism, and the housing of the secondary transmission mechanism is connected to the housing of the primary transmission mechanism via a connecting rod. In this way, the telescopic mechanism can drive the transmission mechanism to move up and down.

[0043] As the first conveyor belt continues to move, the material receiving area carrying the berries passes below the peeling station. Due to the obstruction of the berries and the groove structure, the infrared signal light cannot penetrate to reach the receiver below. However, when a connecting area moves directly below the infrared generator 116, its front window 28 provides a channel for the signal light, allowing the infrared light to instantly pass through the window 28 and be captured by the infrared receiver 117 below. Upon receiving this light signal, the receiver immediately generates an electrical signal and sends it to the motor control unit.

[0044] Because the motor is a variable frequency motor 12, and it has established a communication connection with the infrared receiver 117, the control unit, upon receiving a signal from the infrared receiver 117, sends a specific command to the variable frequency motor 12: within a preset, extremely short time period (less than the time it takes for the connection area to pass through the infrared generator 116), significantly increase the motor's speed. This instantaneous surge in motor speed is transmitted through the transmission mechanism to each forward and reverse drive shaft 113, causing a sudden increase in the rotational speed of all forward-rotating blades 114 and reverse-rotating blades 115. The high-speed rotation of the blades generates a powerful centrifugal force, which quickly dislodges small pieces of fruit peel adhering to the blade surface or stuck in the blade gaps, thus achieving self-cleaning of the blades.

[0045] The technical benefits of this solution are remarkable. First, it achieves complete automation and precision in blade cleaning. The cleaning action is triggered by the structural movement of the conveyor belt itself, synchronized with the production cycle, requiring no manual intervention or additional cleaning steps, thus ensuring production continuity. Second, this infrared-sensor-based triggering mechanism is highly accurate and reliable; cleaning is only triggered when the window 28 representing the connection zone with no material gaps passes through, avoiding accidental activation during normal peeling and preventing excessive accumulation of peel on the blade, which could affect subsequent cutting quality and efficiency. Finally, periodic, instantaneous high-speed peeling operations effectively maintain the cleanliness and working condition of the blade edge, reducing the risk of bacterial growth or cross-contamination caused by peel residue, thus contributing to improved hygiene and safety of the final food product. It also extends the blade maintenance cycle and reduces equipment operation and maintenance costs.

[0046] Furthermore, the refrigeration mechanism includes: A cooling air outlet duct 32 extends through the top of the rapid cooling chamber 31 to the upper layer of the transmission belt; Return air duct 33 extends through the bottom of the quick-cooling chamber 31 to below the upper belt of the transmission belt; The opening of the quick-freezing compartment is also equipped with a windproof curtain 34 made of flexible material.

[0047] The refrigeration outlet duct 32 passes through the top wall panel of the blast freezer and extends downwards to above the upper section of the first conveyor belt 21. This duct is responsible for directly delivering the low-temperature air generated by the refrigeration system and blowing it onto the surface of the berries on the conveyor belt. The return air duct 33 passes through the bottom wall panel of the blast freezer and extends upwards to below the upper section of the conveyor belt. Its main function is to draw in and recover the cold air that has been heated after heat exchange, and send it back to the refrigeration system for further cooling, thereby realizing the recycling of the refrigerant.

[0048] To maintain the low-temperature environment inside the blast freezer and reduce energy waste, air curtains 34 made of flexible material are installed at both openings of the freezer. These air curtains 34 are typically made of PVC or silicone strips and are suspended at the openings in an alternating or overlapping manner. When the first conveyor belt 21 carries berries through the opening, the air curtains 34 are gently pushed open by the conveyor belt and its frame, forming a channel that allows the material to pass through. After the conveyor belt and its load have passed, the flexible air curtains 34 quickly swing back and close again under their own weight, effectively preventing large-scale air exchange between the inside and outside of the freezer.

[0049] In actual operation, the refrigeration unit runs continuously, blowing low-temperature cold air into the quick-freezing chamber through the top refrigeration exhaust duct 32. The cold air envelops the berries on the conveyor belt from top to bottom, rapidly freezing them. After the berries are cooled, the slightly warmer cold air is collected by the bottom return air duct 33 and flows back to the refrigeration unit. In this cycle, the baffle curtain 34 at the chamber opening is crucial, minimizing the intrusion of warm, humid outside air and the escape of internal cold air. For example, without the baffle curtain 34, a large opening would form at the chamber opening, causing a significant loss of cold air, resulting in temperature fluctuations inside the quick-freezing chamber, a significant increase in energy consumption, and even severe frost or ice formation near the opening, affecting the normal operation of the conveyor belt.

[0050] The benefits of this technical solution are multifaceted. It establishes an efficient, closed-loop cold air circulation path, significantly improving refrigeration efficiency and reducing energy consumption. Simultaneously, this structure helps maintain temperature uniformity and stability within the quick-freezing chamber, providing consistent quick-freezing conditions for the berries and ensuring product quality. The flexible windbreak curtain 34 cleverly resolves the contradiction between dynamic conveying and static sealing, ensuring continuous material passage while effectively preserving the cold air within the chamber, preventing cold bridging and icing problems, and ensuring the long-term stable and reliable operation of the entire quick-freezing system 3.

[0051] Furthermore, an airflow regulating valve 35 is installed inside the refrigeration air outlet duct 32. This valve is a movable component installed in the refrigeration air outlet duct 32, and its core function is to change the cross-sectional area of ​​airflow within the duct, thereby precisely controlling the flow rate and speed of the cold air blown from the air outlet onto the material on the conveyor belt.

[0052] The airflow regulating valve 35 can be implemented in various ways. For example, it can be a mechanism similar to a louver, changing the ventilation area by adjusting the angle of the blades; or it can be a component similar to a gate, partially or completely blocking the air duct by raising and lowering it. This regulating valve can be operated manually, for example, by installing a handwheel or lever on the outside of the duct for direct adjustment by the operator; or it can be automatically controlled, for example, by equipping it with an electric or pneumatic actuator that receives signals from a temperature control system or central controller to automatically adjust the opening.

[0053] In actual production operations, operators can flexibly utilize this regulating valve to optimize the quick-freezing effect according to specific process requirements. The required freezing intensity may differ depending on the variety of berries being processed. For example, strawberries with delicate skin and high water content may require a gentler freezing process to prevent skin cracking; in this case, the regulating valve can be closed slightly to reduce the airflow. Conversely, for larger blueberries that require rapid freezing, the regulating valve can be opened wider to achieve maximum airflow for powerful freezing. Furthermore, when ambient temperature changes or production line speed is adjusted, the airflow can be fine-tuned to maintain a stable temperature within the quick-freezing chamber.

[0054] This technical solution has yielded significant benefits. It greatly enhances the controllability and adaptability of the refrigeration system, enabling a single quick-freezing device to flexibly handle the processing requirements of different materials and production capacities, thus improving the equipment's versatility. By precisely controlling the airflow, energy waste caused by over-refrigeration can be avoided, achieving energy conservation and consumption reduction in the production process. Simultaneously, it ensures that materials receive the appropriate freezing intensity, preventing both slow freezing and quality degradation due to insufficient airflow, and avoiding surface drying or mechanical damage to products caused by excessive airflow, thereby effectively guaranteeing and improving the quality of the final product.

[0055] Furthermore, the continuous peeling device also includes: The material feeding system 4 includes a second conveyor belt, which is located above the head end of the first conveyor belt 21; The peeled material collection system 6 includes a third conveyor belt located below the end of the first conveyor belt 21.

[0056] The material feeding system 4 and the peeled material collection system 6 are similar to the material conveying system 2. In addition to the conveyor belt, they also include other necessary components such as supports, left and right side plates, head rollers, tail rollers, and motors.

[0057] The second conveyor belt is responsible for receiving untreated berries from the previous process or storage bin and transporting them to the end at a certain speed. Its end outlet is aligned with the beginning of the first conveyor belt 21, allowing the berries to be poured into the groove 27 of the material receiving area, realizing automatic and continuous material feeding.

[0058] When the first conveyor belt 21, carrying berries that have undergone quick-freezing and peeling, reaches the end, the berries will naturally fall out of the groove 27 or be thrown out due to slight inertia. At this time, the third conveyor belt located directly below it is responsible for receiving these processed berries and smoothly transporting them to the next processing stage, such as a vacuum freeze dryer, or directly to the packaging area.

[0059] By introducing the material feeding system 4 and the post-peeling material collection system 6, automatic material loading and unloading are achieved. The previously independent continuous peeling device is perfectly integrated into the overall berry processing production line, significantly reducing material transfer links and the need for manual intervention between processes. This not only significantly improves the continuity and operational efficiency of the entire production line but also effectively reduces labor intensity and labor costs.

[0060] Furthermore, the first end of the first conveyor belt 21 is inclined downward, and a material recycling system 5 is also provided below the first end of the first conveyor belt 21, the material recycling system 5 including a fourth conveyor belt.

[0061] The downward slope at the beginning of the first conveyor belt 21 forms a gentle slope, which can be achieved by setting corner rollers 29 at the front of the horizontal conveying area of ​​the first conveyor belt 21, below the upper belt and the lower belt.

[0062] When berries are fed from the second conveyor belt above to the first conveyor belt 21, due to factors such as landing accuracy or material bouncing, some berries may not fall accurately into the groove 27 of the material receiving area, but instead fall onto the flat connecting area or edge of the conveyor belt. These misplaced berries will roll or slide down the downward-sloping surface of the conveyor belt due to gravity.

[0063] The material recovery system 5 is designed to collect these berries that failed to load. The fourth conveyor belt is installed directly below the inclined section at the beginning of the first conveyor belt 21, and its conveying direction is generally opposite to that of the first conveyor belt 21. When spilled berries roll off the inclined section of the first conveyor belt 21, they fall directly onto the waiting fourth conveyor belt below.

[0064] In practice, the entire feeding process can be carried out continuously without interruption due to individual spills. For example, during high-speed berry feeding, some berries may bounce off the edge of the first conveyor belt 21 and roll down the ramp. These berries will be caught by the fourth conveyor belt and transported back to the collection box near the start of the production line. Operators can periodically process these recovered berries, either by re-feeding them onto the second conveyor belt or by conducting centralized inspection and cleaning.

[0065] The second, third, and fourth conveyor belts can be set horizontally or at an angle, such as... Figure 1 , 6 As shown in Figures 7 and 8, the second and fourth conveyor belts are inclined downwards near the front end of the first conveyor belt 21, and the third conveyor belt is inclined downwards near the rear end of the first conveyor belt 21. Meanwhile, baffles can be installed on the second, third, and fourth conveyor belts to prevent material from rolling down the conveyor belts, allowing the material to move with the conveyor belts and achieving the purpose of material conveying.

[0066] The aforementioned technical solution, through simple mechanical structural innovation, effectively solves the problem of material spillage that is difficult to completely avoid during automated feeding, reducing pollution to the production environment and material waste. The inclined design utilizes natural gravity to automatically separate and collect substandard materials, while the recycling system enables the automatic collection and reuse of these materials. This not only improves raw material utilization and reduces production costs but also ensures the cleanliness and continuous stable operation of the main production line, reduces downtime caused by frequent manual cleaning of spilled materials, and enhances the overall production efficiency and automation level of the unit.

[0067] The appearance and internal condition of blueberries processed using the traditional direct vacuum freeze-drying method are as follows: Figure 10 As shown, the appearance and internal condition of blueberries obtained after peeling using the continuous peeling device described in this application and then undergoing vacuum freeze-drying are as follows. Figure 11 and 12 As shown. Comparison Figures 10-12 It is easy to see that blueberries processed using the traditional direct vacuum freeze-drying method suffer from increased internal pressure due to the obstruction of the outer skin, preventing water vapor from escaping during the freeze-drying sublimation stage. This increased pressure causes the internal tissues of the blueberry to melt, resulting in the collapse of the freeze-dried blueberry and the formation of an uneven, macroporous structure, which manifests as severe wrinkling. In contrast, blueberries processed by the continuous peeling device and then freeze-dried under vacuum exhibit uniform wrinkling, with no obvious collapse or macroporous structure inside the fruit.

[0068] Although the embodiments of this utility model have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for this utility model. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, this utility model is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A continuous peeling apparatus for pretreatment of berries before vacuum freeze-drying, characterized in that, include: A material conveying system includes a first conveyor belt, which is composed of an alternating material holding area and a connecting area, wherein the material holding area is provided with a groove for holding materials. A quick-freezing system includes a quick-freezing chamber. Each of the two opposite walls of the quick-freezing chamber has an opening for a first conveyor belt to pass through. The quick-freezing chamber is mounted on the upper layer of the first conveyor belt. The upper layer of the first conveyor belt enters the quick-freezing chamber through one opening and exits the quick-freezing chamber through the other opening. A refrigeration mechanism is installed inside the quick-freezing chamber. An automatic peeling system is installed above the upper layer of the first conveyor belt and downstream of the quick-freezing system. The automatic peeling system includes a motor and a transmission mechanism connected to the motor. The output end of the transmission mechanism includes a forward transmission shaft and a reverse transmission shaft with opposite directions. The reverse transmission shaft is hollow inside and open at both ends. The forward transmission shaft coaxially passes through the center of the reverse transmission shaft. Both the forward and reverse transmission shafts are perpendicular to the upper layer of the first conveyor belt. A plurality of forward-rotating blades are evenly arranged circumferentially at the lower end of the forward transmission shaft, and a plurality of reverse-rotating blades are evenly arranged circumferentially at the lower end of the reverse transmission shaft. The cutting edges of the forward-rotating blades and the reverse-rotating blades are opposite to each other to cut the surface of the material in the groove.

2. The continuous peeling apparatus as described in claim 1, characterized in that, The automatic peeling system also includes a telescopic mechanism disposed above the transmission mechanism, the output rod of the telescopic mechanism being perpendicular to the first conveyor belt, and the transmission mechanism being disposed on the output rod of the telescopic mechanism.

3. The continuous peeling apparatus as described in claim 2, characterized in that, Each material holding area is provided with several grooves, which are arranged in a matrix. The transmission mechanism is provided with two rows of output end groups in the width direction of the first conveyor belt. The two rows of output end groups are respectively positioned for two rows of grooves in the groove matrix. Each row of output end groups has one output end arranged with a groove spaced apart, and the positions of each output end in one row of output end groups are staggered from those in the other row of output end groups.

4. The continuous peeling apparatus as described in claim 3, characterized in that, The transmission mechanism includes a primary transmission mechanism and a secondary transmission mechanism; The primary transmission mechanism includes two first transmission shafts distributed along the width direction of the first conveyor belt. A driving gear is provided on the output shaft of the motor. A first driven gear is provided at one end of each of the two first transmission shafts. The two first driven gears are located on both sides of the driving gear and mesh with the driving gear. The two first transmission shafts correspond to two rows of output end groups. Each first transmission shaft is provided with a number of worm gears corresponding to the number of output ends in the corresponding output end group. Each worm gear meshes with a worm perpendicular to the first conveyor belt for transmitting power to the output end. The secondary transmission mechanism includes a second driven gear located at the lower end of the worm, third driven gears meshing on both sides of the second driven gear, a fourth driven gear coaxially connected below the third driven gear, a fifth driven gear coaxially arranged on the reverse transmission shaft, the fourth driven gear meshing with the fifth driven gear, and another third driven gear coaxially arranged on the forward transmission shaft.

5. The continuous peeling apparatus as described in claim 4, characterized in that, The secondary transmission mechanism also includes a housing for accommodating the second driven gear to the fifth driven gear. An infrared generator that emits signal light downwards is connected to the outer wall of the housing. An infrared receiver for receiving the signal light emitted by the infrared generator is provided between the upper and lower belts of the first conveyor belt. Each connecting section of the first conveyor belt has a window at its front end that allows the signal light to pass through; The motor is a variable frequency motor, which is communicatively connected to the infrared receiver. It is used to increase the rotation speed within a preset time after the infrared receiver receives the signal light, so that the forward and reverse blades can throw off the fruit peel.

6. The continuous peeling apparatus as described in claim 1, characterized in that, The refrigeration mechanism includes: A refrigeration air outlet duct extends through the top of the quick-freezing chamber to the upper part of the first conveyor belt. The return air duct passes through the bottom of the quick-freezing chamber and extends to the lower part of the upper belt of the first conveyor belt; The opening of the quick-freezing compartment is also equipped with a windproof curtain made of flexible material.

7. The continuous peeling apparatus as described in claim 6, characterized in that, The cooling air outlet duct is equipped with an air volume regulating valve.

8. The continuous peeling apparatus as described in claim 1, characterized in that, Also includes: The material feeding system includes a second conveyor belt, which is positioned above the head end of the first conveyor belt; The post-peeling material collection system includes a third conveyor belt located below the end of the first conveyor belt.

9. The continuous peeling apparatus as described in claim 1, characterized in that, The first conveyor belt has a downward-sloping head end, and a material recycling system is provided below the head end of the first conveyor belt, the material recycling system including a fourth conveyor belt.

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