Freeze-drier for fruit product processing

Abstract

The application belongs to the technical field of fruit product freeze-drying, and particularly relates to a freeze dryer for fruit product processing, which comprises a box body, a feeding port is formed in the upper wall of the box body, a hollow rotating rod is rotationally connected to the inside of the box body, a plurality of storage cages are fixedly connected to the hollow rotating rod, a motor is installed on the inner wall of the box body, a driving rod is fixedly connected to the output shaft of the motor, first gears are arranged on the driving rod and the hollow rotating rod, and the two first gears are in mesh with each other; and an ice removing assembly is arranged, which is used for centrally conveying ice residues in one direction to improve the ice removing effect. Through the arrangement of the ice removing assembly, the piston cylinder can move forward and backward, and the piston block in the piston cylinder can also move up and down, so that the grid scraper can make a similar sweeping action, and the scraper is prevented from being in contact with the ice surface all the time, and the thin ice layer on the ice surface can be effectively removed.

Description

Technical Field

[0001] This invention belongs to the field of freeze-drying technology for fruit products, and in particular relates to a freeze dryer for processing fruit products. Background Technology

[0002] In the production and processing of fruit products, freeze dryers can be used to freeze-dry the fruit products. This involves using advanced freezing and vacuum drying technology to significantly improve the shelf life, convenience of consumption, and nutritional quality of fruit products.

[0003] Freeze-drying of products generally involves three stages: freezing, sublimation, and re-drying. In traditional freeze-drying equipment, after the product is frozen, the solid ice condensed inside the fruit product vaporizes into gaseous water vapor during the heating and drying process. The water vapor adheres to the bottom or side wall of the equipment cavity (near the inner wall of the condenser tube) at a lower temperature and gradually forms an ice layer. The ice layer covers the inner wall of the equipment cavity, making it difficult for the low temperature generated by the condenser tube to penetrate the ice layer and conduct to the inside of the equipment. As a result, before the next batch of fruit products is freeze-dried, time needs to be spent observing and cleaning the ice layer covering the inner cavity of the equipment. For freeze dryers with condenser tubes at the bottom, the traditional de-icing method uses a motor-driven scraper to move back and forth. However, with this method, the scraper is always in contact with the icing surface, making it impossible to transport and concentrate the scraped ice in one direction. This not only greatly limits the de-icing effect, but also causes the ice to accumulate and, if not removed from the icing surface in time, easily form larger ice blocks during the freezing of the next batch of products, affecting the subsequent freeze-drying process. In addition, during the re-drying stage, when heating the fruit products, traditional electric heating wires are used. However, because the defrosting machine is close to a vacuum and lacks a heat transfer medium, the heat generated by the heating wires can only be transferred to the fruit products through thermal radiation. This method results in slow heating of the fruit products, and the uniformity of heating is difficult to guarantee due to the influence of the heating element's position. Summary of the Invention

[0004] The purpose of this invention is to address the problems mentioned in the background art by providing a freeze dryer for fruit processing that enables the grid scraper to perform a sweeping motion, avoiding the scraper from being in constant contact with the icy surface and thus failing to remove ice slag, thereby effectively removing a thin layer of ice from the icy surface.

[0005] To achieve the above objectives, the present invention adopts the following technical solutions:

[0006] A freeze dryer for fruit product processing includes a housing, an inlet on the upper wall of the housing, a hollow rotating rod rotatably connected inside the housing, a plurality of storage cages fixedly connected to the hollow rotating rod, a motor installed on the inner wall of the housing, a drive rod coaxially fixedly connected to the output shaft of the motor, and a first gear coaxially fixed on both the drive rod and the hollow rotating rod, with two first gears meshing with each other;

[0007] A de-icing assembly is used to concentrate and transport ice debris in one direction to improve the de-icing effect. The de-icing assembly includes a transmission rod rotatably connected to the inner wall of the housing, the transmission rod being driven by a hollow rotating rod. A piston cylinder is slidably connected inside the housing, and a piston block is slidably and sealingly connected to the inner wall of the piston cylinder. A second gear is fixedly connected to the portion of the transmission rod extending into the piston cylinder. A toothed groove that meshes with the second gear is provided in the middle of the piston block. An extension rod is fixedly connected to the bottom end of the piston block. A grid scraper is connected to the portion of the extension rod extending below the piston cylinder. A slide rail is fixedly connected to the inner wall of the housing, and a roller that cooperates with the slide rail is rotatably connected to the side wall of the extension rod.

[0008] Preferably, each of the multiple storage cages has a material placement opening on its peripheral sidewall, and the material placement opening is hinged to a closed door.

[0009] Preferably, both the transmission rod and the hollow rotating rod are provided with synchronous pulleys, and a synchronous belt is sleeved between the two synchronous pulleys.

[0010] Preferably, the slide rail includes a straight section and two semicircular sections, with the two semicircular sections connected to the two ends of the straight section. The roller rolls along the slide rail for one revolution, and the second gear also rolls along the tooth groove for one revolution.

[0011] Preferably, the housing is provided with a guide rod inside, the guide rod is horizontally arranged, and its two ends are respectively fixed to two side walls opposite to the housing, and the piston cylinder is slidably connected to the lower end of the guide rod.

[0012] Preferably, the device further includes a heating assembly for providing the heat required for the sublimation of ice crystals in the fruit product. The heating assembly includes a heating box fixedly connected to the outer wall of the box body. The upper end of the heating box is provided with an oil inlet pipe, which is rotatably and sealed to one end of a hollow rotating rod. The heating box is connected to the interior of the hollow rotating rod through the oil inlet pipe. An oil outlet pipe is provided on the side wall of the heating box. The oil outlet pipe extends into the piston cylinder and is located above the piston block. The end of the piston cylinder away from the oil outlet pipe is sealed and connected to an oil delivery pipe. The oil delivery pipe is rotatably and sealed to the other end of the hollow rotating rod. The piston cylinder is connected to the interior of the hollow rotating rod through the oil delivery pipe.

[0013] Preferably, the heating box and the hollow rotating rod are filled with silicone oil, and the heating box has an opening that is sealed by an elastic rubber sheet.

[0014] Preferably, the oil outlet pipe and the oil delivery pipe are both configured as flexible hoses at the ends near the piston cylinder, and each flexible hose is equipped with a one-way valve. The piston cylinder is configured as a flat cylindrical shape, and a vent hole is provided at its lower end.

[0015] Compared with existing technologies, the freeze dryer for fruit product processing has the following advantages:

[0016] 1. This invention, by setting up a de-icing component, utilizes a motor to drive a drive rod during freeze-drying. This drive rod rotates via two first gears, which in turn drive a hollow rotating rod. The hollow rotating rod then drives a transmission rod, which in turn drives a second gear. Through a slide rail on the inner wall of the chamber and rollers that cooperate with the piston block, the piston cylinder moves back and forth, and the piston block moves up and down alternately. This allows the grid scraper to perform a sweeping motion, preventing the scraper from constantly contacting the icy surface and failing to remove ice slag. This effectively removes the thin layer of ice from the icy surface. Compared to scrapers that can only move back and forth, this invention can not only scrape away ice slag but also concentrate it in one direction, preventing ice slag from forming larger ice blocks near the condenser tube during the freezing process of the next batch of products.

[0017] 2. This invention utilizes a hollow rotating rod and storage cages, employing silicone oil as a heat transfer medium. Silicone oil has a large heat capacity, which can buffer temperature fluctuations to a certain extent, thus maintaining temperature stability. Multiple storage cages are installed on the hollow rotating rod, transferring the heat from the silicone oil to the storage cages via thermal conduction. From there, the heat is transferred to the fruit products. Compared to traditional radiative heating, the fruit products can directly contact the storage cages for heat conduction, resulting in faster heating. Furthermore, during the rotation of the storage cages, different surfaces of the storage cages contact the fruit products, ensuring uniform heating and preventing uneven heating that could affect the sublimation rate.

[0018] 3. This invention, through the setting of a heating component, utilizes a motor-driven hollow rotating rod to rotate, simultaneously driving the transmission rod and the second gear to rotate. Simultaneously, the piston block inside the piston cylinder moves up and down, forming a suction pump structure. When the piston block moves upward, it draws silicone oil from the heating chamber into the piston cylinder; when the piston block moves downward, it pumps the silicone oil from the piston cylinder into the hollow rotating rod. The hollow rotating rod then conducts the heat of the silicone oil to the storage cage to heat the material. The silicone oil flows through the hollow rotating rod and, under the negative pressure inside the heating chamber, flows back into its interior, replenishing the silicone oil with heat. This achieves cyclic conductive heating, ensuring a continuous supply of heat. This heating method is fast and has high temperature controllability, further improving the heating effect on fruit products.

[0019] 4. This application uses a single motor as a power source, which can simultaneously drive the rotation of the storage cage, the de-icing of the grid scraper, and the circulating heating of the silicone oil, simplifying the product structure while ensuring the freeze-drying effect of the materials. Attached Figure Description

[0020] Figure 1 This is a three-dimensional structural diagram of the freeze dryer for fruit product processing provided by the present invention;

[0021] Figure 2 This is a cross-sectional view of the freeze dryer for fruit product processing provided by the present invention;

[0022] Figure 3 yes Figure 2 Enlarged view of point A in the middle;

[0023] Figure 4 yes Figure 2 Enlarged view of point B in the middle;

[0024] Figure 5 This is a cross-sectional view of the piston cylinder in the freeze dryer for fruit product processing provided by the present invention.

[0025] In the diagram, 1. Box body; 11. Feed inlet; 12. Hollow rotating rod; 13. Storage cage; 14. Motor; 15. Drive rod; 16. First gear; 2. De-icing assembly; 21. Transmission rod; 22. Piston cylinder; 23. Piston block; 24. Second gear; 25. Tooth groove; 26. Extension rod; 27. Grille scraper; 28. Slide rail; 29. ​​Roller; 3. Synchronous pulley; 4. Synchronous belt; 5. Heating assembly; 51. Heating box; 52. Oil inlet pipe; 53. Oil outlet pipe; 54. Oil delivery pipe. Detailed Implementation

[0026] The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0027] Example: Refer to Figures 1 to 5 A freeze dryer for fruit processing includes a housing 1, with a feed inlet 11 on the upper wall of the housing 1 and a sealing cover at the feed inlet 11. A hollow rotating rod 12 is rotatably connected inside the housing 1, and multiple storage cages 13 are fixedly connected to the hollow rotating rod 12. A motor 14 is installed on the inner wall of the housing 1, and a drive rod 15 is coaxially fixedly connected to the output shaft of the motor 14. A first gear 16 is coaxially fixed on both the drive rod 15 and the hollow rotating rod 12, and the two first gears 16 mesh with each other.

[0028] The bottom wall of the chamber 1 is equipped with a condenser coil (not shown in the figure). The condenser coil is connected to the refrigeration system of the freeze dryer. The condenser coil can cool the inside of the chamber 1. The refrigeration system is the same as that of a traditional freeze dryer and will not be described here.

[0029] Each of the storage cages 13 has a material placement opening on its perimeter wall, and the material placement opening is hinged to a closed door (not shown in the figure). The material is placed in through the placement opening, and the closed door is closed and locked after placement.

[0030] To address the problems in existing technologies where traditional electric heating wires are used to heat fruit products after freeze-drying, but the near-vacuum environment inside the defrosting machine lacks a heat transfer medium, resulting in slow heating and uneven heating due to the layout of the heating elements, this invention addresses these issues. By incorporating a hollow rotating rod 12 and storage cages 13, silicone oil is used as the heat transfer medium after freeze-drying. Silicone oil has a large heat capacity, which can buffer temperature fluctuations and maintain temperature stability. Multiple storage cages 13 on the hollow rotating rod 12 transfer the heat from the silicone oil to the cages. Compared to the radiative heating of traditional heating wires and electric heating tubes, the fruit products can directly contact the storage cages 13 for heat conduction, resulting in faster heating. During rotation, the storage cages 13 contact different surfaces of the fruit products, ensuring uniform heating and preventing uneven heating that could affect the sublimation rate.

[0031] The de-icing assembly 2 is used to concentrate and transport ice slag in one direction to improve the de-icing effect. The de-icing assembly 2 includes a transmission rod 21 rotatably connected to the inner wall of the housing 1, a piston cylinder 22 slidably connected inside the housing 1, a piston block 23 slidably connected to the inner wall of the piston cylinder 22, a second gear 24 fixedly connected to the part of the transmission rod 21 extending into the piston cylinder 22, a tooth groove 25 meshing with the second gear 24 in the middle of the piston block 23, an extension rod 26 fixedly connected to the bottom end of the piston block 23, a grid scraper 27 fixedly connected to the part of the extension rod 26 extending below the piston cylinder 22, a slide rail 28 fixedly connected to the inner wall of the housing 1, the slide rail 28 being horizontally arranged, and a roller 29 cooperating with the slide rail 28 on the side wall of the extension rod 26.

[0032] Both the transmission rod 21 and the hollow rotating rod 12 are equipped with synchronous pulleys 3, and a synchronous belt 4 is sleeved between the two synchronous pulleys 3. Therefore, when the motor 14 drives the hollow rotating rod 12 to rotate, the hollow rotating rod 12 can drive the transmission rod 21 to rotate with the synchronous belt 4, so that the second gear 24 in the piston cylinder 22 can rotate continuously, thus eliminating the need for an additional drive source to scrape away ice shavings.

[0033] The slide rail 28 includes a straight section and two semicircular sections, with the two semicircular sections connected to the two ends of the straight section. The roller 29 rolls one revolution along the slide rail 28, and the second gear 24 also rolls one revolution along the tooth groove 25. Therefore, through the continuous movement of the roller 29 and the slide rail 28, the piston block 23 inside the piston cylinder 22 always moves along a predetermined trajectory. When the roller 29 rolls along the straight section of the slide rail 28, the second gear 24 also meshes along the straight section of the tooth groove 25. Since the second gear 24 is rotatably connected to the inner wall of the housing 1 via the transmission rod 21, it can only rotate. Rotating the piston block 23 drives it to move horizontally, which in turn drives the piston cylinder 22 to move horizontally. When the roller 29 rolls along the semicircular section of the slide rail 28, the second gear 24 also meshes along the semicircular section of the tooth groove 25. Since the movement trajectory of the roller 29 is a semicircular arc, it can drive the piston cylinder 22 to move slightly horizontally while simultaneously driving the piston block 23 to move vertically. The piston block 23 drives the grid scraper 27 to move up and down synchronously through the extension rod 26. When the roller 29 rolls one revolution along the slide rail 28, the corresponding grid scraper 27 can achieve a sweeping-like action.

[0034] The housing 1 has a guide rod inside, and the piston cylinder 22 is slidably connected to the lower end of the guide rod, which ensures that the piston block 23 can drive the piston cylinder 22 to make horizontal displacement, but the piston block 23 can make vertical displacement relative to the piston cylinder 22.

[0035] Specifically, the scraper blades of the grid scraper 27 should be set perpendicular to the direction of its horizontal displacement in order to remove the ice layer. At the same time, the extension rod 26 can be elastically connected to the grid scraper 27 through a spring to avoid long-term contact and friction wear between the grid scraper 27 and the ice surface, thus extending its maintenance cycle.

[0036] To address the problems of traditional de-icing methods requiring additional drive components, where scrapers move back and forth and remain in constant contact with the icing surface, failing to concentrate ice debris in one direction, and causing it to clump together and form larger blocks, thus significantly limiting de-icing efficiency, this invention addresses these issues by incorporating a de-icing component 2. During the material heating stage, a motor 14 drives a drive rod 15 to rotate, which in turn drives a hollow rotating rod 12 via two first gears 16. The hollow rotating rod 12 then rotates the storage cage 13 above it, rapidly and evenly cooling the fruit products within. Simultaneously, the hollow rotating rod 12 is driven by a synchronous pulley 3 and a synchronous belt 4. When rod 21 rotates, the second gear 24 on transmission rod 21 rotates. Through the mutual cooperation between the second gear 24 and the tooth groove 25 on piston block 23, and through the restriction of the movement trajectory by slide rail 28, the grid scraper 27 can both move horizontally to complete the action of scraping off the ice layer, and lift itself up so that it does not contact the ice surface during the return process, passing over the scraped ice slag and avoiding bringing the ice slag back. When the scraping action of the next cycle begins, and because the ice slag scraped off in the previous cycle has a certain motion inertia, the ice slag will move a certain distance in the opposite direction of the scraping, which can be pushed by the grid scraper 27 in one direction, and finally push the scraped ice slag out of the coverage area of ​​the condenser coil, so as to avoid affecting the cooling effect of the condenser coil on the cabinet 1.

[0037] The present invention also includes a heating assembly 5, which provides the heat required for the sublimation of ice crystals in fruit products. The heating assembly 5 includes a heating box 51 fixedly connected to the outer wall of the box body 1. The heating box 51 is equipped with an adjustable electric heating element, which can set a suitable heating temperature according to the heating requirements of different materials. The upper end of the heating box 51 is provided with an oil inlet pipe 52, which is sealed and rotatably connected to one end of the hollow rotating rod 12. The heating box 51 is connected to the interior of the hollow rotating rod 12 through the oil inlet pipe 52. The side wall of the heating box 51 is provided with an oil outlet pipe 53, which extends to the part of the piston cylinder 22 located above the piston block 23. The end of the piston cylinder 22 away from the oil outlet pipe 53 is sealed and connected to an oil delivery pipe 54. The oil delivery pipe 54 is sealed and rotatably connected to the other end of the hollow rotating rod 12. The piston cylinder 22 is connected to the interior of the hollow rotating rod 12 through the oil delivery pipe 54.

[0038] The heating chamber 51 and the hollow rotating rod 12 are filled with silicone oil. The oil outlet pipe 53 and the oil delivery pipe 54 are both made into flexible hoses near the piston cylinder 22. The hoses are made of low-temperature resistant hoses. The hoses are designed to avoid affecting the movement of the piston cylinder 22. Each hose is equipped with a one-way valve. The piston cylinder 22 is a flat cylindrical shape with a vent at its lower end. The one-way valve ensures that when the piston block 23 moves downward relative to the piston cylinder 22, the silicone oil in the heating chamber 51 can only be delivered to the piston cylinder 22 through the oil outlet pipe 53. When the piston block 23 moves upward relative to the piston cylinder 22, the silicone oil in the piston cylinder 22 can only be pumped to the hollow rotating rod 12 through the oil delivery pipe 54. It is worth mentioning that the heating chamber 51 has an opening, which is sealed by an elastic rubber sheet. The elastic rubber sheet acts like a breathing diaphragm, allowing the volume of the heating chamber 51 to change, ensuring that the silicone oil can circulate normally within the heating assembly.

[0039] To further improve the heating effect on fruit products, this invention incorporates a heating component 5. While the motor 14 drives the hollow rotating rod 12 to rotate, simultaneously rotating the transmission rod 21 and the second gear 24, the piston block 23 inside the piston cylinder 22 moves up and down, forming a suction pump structure. When the piston block 23 moves upward, it draws the silicone oil from the heating chamber 51 into the piston cylinder 22. When the piston block 23 moves downward, it pumps the silicone oil from the piston cylinder 22 into the hollow rotating rod 12. The hollow rotating rod 12 then conducts the heat from the silicone oil to the storage cage 13 to heat the material. The silicone oil, flowing through the hollow rotating rod 12, is returned to its interior under the negative pressure within the heating chamber 51, replenishing its heat and achieving cyclic conductive heating, further improving the heating effect on fruit products.

[0040] The functional principle of this invention can be explained through the following operational methods:

[0041] After the material is frozen, the vacuum drying heating stage begins. The motor 14 drives the drive rod 15 to rotate, which in turn drives the hollow rotating rod 12 to rotate via the two first gears 16. The hollow rotating rod 12 drives the storage cage 13 on it to rotate, uniformly cooling the fruit products inside the storage cage 13. At the same time, the hollow rotating rod 12 drives the transmission rod 21 to rotate via the synchronous pulley 3 and the synchronous belt 4. The second gear 24 on the transmission rod 21 rotates. Through the interaction between the second gear 24 and the tooth groove 25 on the piston block 23, the piston cylinder 22 moves back and forth while the piston block 23 inside moves up and down. This allows the grid scraper 27 to make a sweeping motion, preventing the grid scraper 27 from always being in contact with the ice surface and thus failing to remove the ice slag, effectively removing the thin layer of ice on the ice surface.

[0042] After freeze-drying, silicone oil is used as a heat transfer medium. It has a large heat capacity and can buffer temperature fluctuations to a certain extent, thereby maintaining temperature stability. Through multiple storage cages 13 set on the hollow rotating rod 12, the heat of the silicone oil is transferred to the storage cages 13. Compared with traditional heat radiation heating, the fruit products can directly contact the storage cages 13 for heat conduction, which makes the heat conduction speed faster. During the rotation of the storage cages 13, different surfaces of the fruit products are in contact, which makes the fruit products heat up evenly.

[0043] While the second gear 24 rotates, the piston block 23 inside the piston cylinder 22 moves up and down, forming a suction pump structure. When the piston block 23 moves up, it can draw the silicone oil in the heating box 51 into the piston cylinder 22. When the piston block 23 moves down, it can pump the silicone oil in the piston cylinder 22 into the hollow rotating rod 12. The hollow rotating rod 12 conducts the heat of the silicone oil to the storage cage 13 to heat the material. The silicone oil flows through the hollow rotating rod 12 and, under the action of negative pressure in the heating box 51, flows back into its interior to replenish the heat of the silicone oil, realizing a circulating conduction heating.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A freeze dryer for processing fruit products, comprising a housing (1), characterized in that, The upper wall of the box (1) is provided with a feed inlet (11). A hollow rotating rod (12) is rotatably connected inside the box (1). Multiple storage cages (13) are fixedly connected to the hollow rotating rod (12). A motor (14) is installed on the inner wall of the box (1). A drive rod (15) is coaxially fixedly connected to the output shaft of the motor (14). A first gear (16) is coaxially fixed on both the drive rod (15) and the hollow rotating rod (12). The two first gears (16) mesh with each other. A de-icing assembly (2) is used to concentrate and transport ice slag in one direction to improve the de-icing effect. The de-icing assembly (2) includes a transmission rod (21) rotatably connected to the inner wall of the housing (1). The transmission rod (21) is connected to a hollow rotating rod (12). A piston cylinder (22) is slidably connected inside the housing (1). A piston block (23) is slidably connected to the inner wall of the piston cylinder (22). The transmission rod (21) extends into the piston cylinder (22). A second gear (24) is fixedly connected. The piston block (23) has a tooth groove (25) in the middle that meshes with the second gear (24). An extension rod (26) is fixedly connected to the bottom end of the piston block (23). A grid scraper (27) is connected to the part of the extension rod (26) that extends to the bottom of the piston cylinder (22). A slide rail (28) is fixedly connected to the inner wall of the box (1). A roller (29) that cooperates with the slide rail (28) is rotatably connected to the side wall of the extension rod (26). The slide rail (28) includes a straight section and two semicircular sections, with the two semicircular sections connected to the two ends of the straight section. The roller (29) rolls one revolution along the slide rail (28), and the second gear (24) also rolls one revolution along the tooth groove (25). It also includes a heating assembly (5), which provides the heat required for the sublimation of ice crystals in the fruit product. The heating assembly (5) includes a heating box (51) fixedly connected to the outer wall of the box body (1). The upper end of the heating box (51) is provided with an oil inlet pipe (52). The oil inlet pipe (52) is rotatably and sealed to one end of the hollow rotating rod (12), and the heating box (51) is connected to the inside of the hollow rotating rod (12) through the oil inlet pipe (52). The heating box (51) is provided with an oil outlet pipe (53) on its side wall. The oil outlet pipe (53) extends into the piston cylinder (22) and is located above the piston block (23). The piston cylinder (22) is connected to an oil supply pipe (54) through a sealed connection at one end away from the oil outlet pipe (53). The oil supply pipe (54) is rotatably connected to the other end of the hollow rotating rod (12) in a sealed manner. The piston cylinder (22) is connected to the interior of the hollow rotating rod (12) through the oil supply pipe (54). The oil outlet pipe (53) and the oil delivery pipe (54) are both configured as flexible hoses at the end near the piston cylinder (22), and each flexible hose is equipped with a one-way valve. The piston cylinder (22) is configured as a flat cylindrical shape, and a vent hole is provided at its lower end.

2. The freeze dryer for fruit product processing according to claim 1, characterized in that, Each of the multiple storage cages (13) has a material placement opening on its periphery wall, and the material placement opening is hinged to a closed door.

3. The freeze dryer for fruit product processing according to claim 1, characterized in that, Both the transmission rod (21) and the hollow rotating rod (12) are equipped with synchronous pulleys (3), and a synchronous belt (4) is sleeved between the two synchronous pulleys (3).

4. The freeze dryer for fruit product processing according to claim 1, characterized in that, The box (1) is provided with a guide rod inside. The guide rod is horizontally set and its two ends are fixed to the two side walls opposite to the box (1). The piston cylinder (22) is slidably connected to the lower end of the guide rod.

5. The freeze dryer for fruit product processing according to claim 1, characterized in that, The heating box (51) and the hollow rotating rod (12) are filled with silicone oil. The heating box (51) has an opening, which is sealed by an elastic rubber sheet.

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