Coffee cold extraction liquid low-temperature vacuum concentration equipment

Abstract

The invention relates to the technical field of coffee concentration and separation, in particular to low-temperature vacuum concentration equipment for coffee cold extraction liquid. The device comprises a concentration cavity, a supporting frame is fixedly connected to the surface of the concentration cavity, a buffering discharging assembly is fixedly connected to the top of the concentration cavity, a filtering assembly is arranged at the bottom of an inner cavity of the buffering discharging assembly, and a spiral discharging frame is rotationally arranged in the inner cavity of the buffering discharging assembly and used for slowing down the coffee falling speed. And the particles are uniformly distributed on the surface of the filter assembly. The spiral discharging frame is driven to rotate by utilizing driving force for initial coffee discharging, meanwhile, the driving assembly provides auxiliary power to ensure stable operation, and at the moment, the spiral discharging frame synchronously drives the stirring assembly to rotate, so that coffee liquid starts to be stirred at the moment of entering the concentration cavity, small molecule particles are rapidly dispersed and prevented from being precipitated or layered at the bottom of the cavity, and the concentration effect is improved. And uniform and stable components of the concentrated solution are ensured, and automatic linkage of'discharging and stirring 'is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of coffee concentrate separation, and more specifically, to a low-temperature vacuum concentration device for cold-brewed coffee liquid. Background Art

[0002] In the field of coffee processing, the traditional high-temperature concentration process, with its relatively high evaporation efficiency, used to be the mainstream method for concentrating cold-brewed coffee liquid. However, in a high-temperature environment, a large amount of heat-sensitive aroma components in coffee will volatilize, and components such as tannic acid may decompose to produce a burnt bitter taste, seriously damaging the flavor quality of coffee and making it difficult to meet consumers' pursuit of high-quality coffee. As consumers' requirements for coffee quality and taste continue to increase, cold-brewed coffee is becoming increasingly popular in the market due to its unique flavor and taste. To meet the needs of large-scale production and market supply, an efficient concentration device is required to process cold-brewed liquid; For example, Chinese Patent No. CN221412486U, a coffee liquid freezing concentration device, includes a box body. A partition is fixedly connected inside the box body, and a refrigerator is fixedly connected inside the partition. For this coffee liquid freezing concentration device, the coffee liquid is poured into the box body, and the coffee liquid is cooled on the partition. After cooling, the coffee liquid can quickly crystallize in the crystallization tube, and after crystallization, it falls into the filter screen for filtration and separation. After filtration, the coffee liquid is inspected by the inspection component inside the box body. If it is qualified, it will flow into the collection tank for collection by opening the valve. If it is unqualified, the circulation pump will be started to make the unqualified coffee liquid enter the water inlet pipe and then be discharged from the water outlet pipe to the inside of the box body for circulation. When it is necessary to clean the filter screen, the motor drives the threaded rod to rotate, and is limited by the limit rod, so that the moving rod drives the cleaning brush to move back and forth, thereby cleaning the residue on the filter screen into the trash can; Considering the above device in the filtration link, generally, the coffee liquid is directly poured into the inside of the box body and filtered by relying on gravity naturally. At this time, impurities such as suspended particles and colloids in the coffee liquid are extremely easy to penetrate the filter holes of the filter screen and flow out directly under the action of gravity, affecting the clarity and purity of the concentrated liquid. Summary of the Invention

[0003] The purpose of the present invention is to provide a low-temperature vacuum concentration device for cold-brewed coffee liquid to solve the problems raised in the above background art.

[0004] To achieve the above purpose, the present invention provides a low-temperature vacuum concentration device for cold-brewed coffee liquid, including a concentration cavity. A support frame is fixedly connected to the surface of the concentration cavity, a buffer feeding component is fixedly connected to the top of the concentration cavity, and a filtering component is arranged at the bottom of the inner cavity of the buffer feeding component; A spiral feeding rack is rotatably arranged in the inner cavity of the buffer feeding assembly, which is used to slow down the falling speed of coffee and make it evenly distributed on the surface of the filtering assembly. The filtering assembly is used to intercept macromolecular impurities and permeate small molecular flavor substances; A vacuum pump is fixedly connected to the outer wall of the concentration cavity, and a stirring assembly is arranged in its inner cavity. A driving assembly is fixedly connected to the top of the concentration cavity. The driving assembly simultaneously drives the spiral feeding rack to rotate and drives the stirring assembly to rotate in the concentration cavity to realize the uniform mixing of coffee liquid; A scraper is arranged at the bottom of the spiral feeding rack. When the driving assembly drives the spiral feeding rack to rotate, the scraper scrapes the surface of the filtering assembly to prevent impurities from blocking the filtering assembly.

[0005] When the coffee stock solution enters the inner cavity of the buffer feeding assembly, the liquid will contact the surface of the spiral structure of the spiral feeding rack. The coffee liquid flows along the spiral blade and applies a tangential thrust to the spiral surface to form a rotational moment. At this time, the driving assembly provides auxiliary power to further enhance the rotational stability of the spiral feeding rack, so that the coffee liquid spreads evenly on the surface of the filtering assembly at a controllable flow rate, avoiding local concentrated impact resulting in impurities penetrating the filter screen. At the same time, the scraper fixed at the bottom of the spiral feeding rack continuously scrapes the surface of the filtering assembly during rotation, timely removing the deposited impurities, preventing the filter holes from being blocked, and ensuring the long-term stable filtration efficiency.

[0006] As a further improvement of this technical solution, a jacket is opened in the inner cavity of the concentration cavity, a water inlet pipe is opened on the surface of the concentration cavity, a water outlet pipe is opened on the surface of the concentration cavity, and the water inlet pipe and the water outlet pipe are communicated with the jacket. The water inlet pipe is located on the upper surface of the concentration cavity, and the water outlet pipe is located on the lower surface of the concentration cavity, forming a circulation path of low-temperature water flowing from top to bottom in the jacket. The jacket is arranged around the inner wall of the concentration cavity for one week, and a temperature sensor is fixedly connected to the surface of the concentration cavity; As a further improvement of this technical solution, a feeding device is fixedly connected to the surface of the spiral feeding rack. The top of the feeding device is provided with a feeding port. The feeding device is located above the concentration cavity, and the bottom of the feeding device is fixedly connected with a feeding pipe. The end of the feeding pipe is communicated with the inner cavity of the concentration cavity. The top of the inner cavity of the feeding device is rotatably connected with a rotating shaft through a bearing. A transmission gear meshing with the output gear of the driving assembly is arranged on the outer circumference of the rotating shaft. The spiral feeding rack is in an inclined downward spiral structure and is fixedly wound around the surface of the rotating shaft. An annular limiting groove is opened on the inner wall of the feeding device. A sliding block is fixedly connected to the surface of the spiral feeding rack, and the surface of the sliding block slides on the inner wall of the annular limiting groove. The annular limiting groove is annularly arranged around the inner wall of the feeding device; The spiral feeding rack is of a spiral structure, which converts the poured coffee liquid from concentrated impact into slow flow along the spiral track, effectively slowing down the falling speed of the liquid and making it evenly spread on the surface of the lower filtering component. The tangential thrust generated by the coffee liquid flowing along the spiral track drives the spiral feeding rack to drive the rotating shaft to rotate. At the same time, when the spiral feeding rack rotates due to the operation of the driving component, it remains stable, realizing liquid dispersion. The sliding fit between the annular limiting groove and the slider provides a stable guide for the rotation of the spiral feeding rack and restricts its radial displacement.

[0007] As a further improvement of this technical solution, the filtering component includes a filtering support fixedly connected to the inner wall of the feeding device. The inner wall of the filtering support includes an upper microfiltration membrane and a lower precision filtration membrane. The upper microfiltration membrane is used to intercept visible suspended matters such as coffee powder residues to prevent blocking the lower precision filtration membrane. The lower precision filtration membrane is used to selectively intercept macromolecules while allowing small molecule aroma components to pass through. The filtering support is vertically installed directly below the spiral feeding rack, and the surface of the scraping plate slides on the surface of the upper microfiltration membrane, and the bottom of the filtering support is suspended, leaving a space from the bottom of the inner cavity of the feeding device; The coffee liquid is evenly spread along the spiral of the spiral feeding rack on the surface of the lower upper microfiltration membrane. Since the filtering support is vertically installed directly below the spiral feeding rack, the liquid falling path is short and concentrated, which can reduce splashing. The upper microfiltration membrane intercepts large particle impurities in the coffee liquid, and the lower precision filtration membrane selectively intercepts macromolecular substances while allowing small molecule aroma components to pass through, which can effectively improve the purity of the coffee concentrate and retain the aroma components of the coffee.

[0008] As a further improvement of this technical solution, a chute is opened at the top of the feeding device. A rotating plate is slidably connected to the inner wall of the chute. The inner cavity of the concentration cavity is rotatably connected to a rotating shaft by means of a bearing. The end of the rotating shaft penetrates through the bottom of the feeding device and is fixedly connected to the rotating shaft. A stirring rod is fixedly connected to the surface of the rotating shaft. The bottom of the concentration cavity is fixedly communicated with a discharge pipe; Move the rotating plate to slide along the chute so that its bottom fits on the surface of the feeding port to seal the device. During this process, the remaining coffee liquid in the spiral feeding rack will continuously drive the rotating shaft to rotate, so that the stirring component continuously mixes and stirs the coffee liquid entering the inner cavity of the concentration cavity.

[0009] Compared with the prior art, the beneficial effects of the present invention are: 1. In this low-temperature vacuum concentration equipment for coffee cold extraction liquid, by rotatably arranging the spiral feeding rack inside the feeding device, when the coffee liquid flows along the spiral track on the surface of the spiral feeding rack, the tangential force generated drives its rotation, enabling the coffee liquid to be evenly distributed on the surface of the upper microfiltration membrane. Initial rotation is achieved by relying on the hydrodynamic action of the coffee liquid flow. At the same time, a driving component is provided to supply auxiliary power to ensure stable operation, preventing the coffee liquid from being poured only from one position and ensuring that the surface of the filtration component is fully covered, improving the filtration efficiency. Meanwhile, the rotating spiral feeding can reduce the impact force of the liquid, preventing large particle impurities from directly penetrating the upper microfiltration membrane. The scraper rotates with the spiral feeding rack to continuously scrape the surface of the upper microfiltration membrane, preventing blockage and maintaining stable filtration. The sliding fit of the slider and the annular limiting groove is used to restrict the rotation position of the spiral feeding rack.

[0010] 2. In this low-temperature vacuum concentration equipment for coffee cold extraction liquid, by utilizing the driving force of the initial coffee feeding to drive the rotation of the spiral feeding rack, and at the same time, the driving component provides auxiliary power to ensure stable operation. At this time, the spiral feeding rack will synchronously drive the stirring component to rotate, causing the coffee liquid to start stirring instantly when it enters the concentration cavity, quickly dispersing small molecule particles, preventing them from precipitating or stratifying at the bottom of the cavity, ensuring the uniform and stable composition of the concentrated liquid, and achieving the automatic linkage of "feeding and stirring". Through the cooperation of the rotating plate at the top of the feeding device and the chute, the feeding port can be quickly sealed during equipment operation to prevent external air from entering the concentration cavity, ensuring that the vacuum pump maintains a stable negative pressure environment, guaranteeing the efficient progress of the low-temperature concentration process, and avoiding the influence of air pressure fluctuations on the concentration effect and flavor retention. Even after the rotating plate seals the feeding port, the residual coffee liquid in the spiral feeding rack can still drive the rotating shaft to continue rotating, keeping the stirring component in working state and continuously mixing the coffee liquid in the cavity, avoiding problems such as local concentration unevenness or precipitation caused by the suspension of feeding. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is the overall structure assembly schematic diagram of the present invention; Figure 2 It is the overall structure schematic diagram of the inner cavity of the feeding device of the present invention; Figure 3 It is the structure schematic diagram of the spiral feeding rack of the present invention; Figure 4 For the present invention Figure 2 The enlarged structure schematic diagram at position A; Figure 5 It is the structure schematic diagram of the scraper of the present invention; The meanings of each label in the figure are as follows: 100, concentration cavity; 101, discharge pipe; 102, jacket; 110, vacuum pump; 120, support frame; 1021, water inlet pipe; 1022, water outlet pipe; 200, Stirring assembly; 210, Rotating shaft; 220, Stirring rod; 300, Buffer feeding assembly; 310, Ring-shaped fixing frame; 320, Feeding device; 3201, Ring-shaped limiting groove; 3202, Rotating shaft; 3203, Chute; 3204, Rotating plate; 330, Spiral feeding frame; 3301, Scraper; 3302, Slide block; 340, Feed pipe; 400, Filtering assembly; 410, Filtering bracket; 4101, Upper microfiltration membrane; 4102, Lower precision filtration membrane; 500, Driving assembly. Specific embodiments

[0012] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention.

[0013] Embodiment 1 Please refer to Figures 1-5 As shown, this embodiment provides a low-temperature vacuum concentration device for coffee cold brew liquid, including a concentration cavity 100. A support frame 120 is fixedly connected to the surface of the concentration cavity 100. A buffer feeding assembly 300 is fixedly connected to the top of the concentration cavity 100. A filtering assembly 400 is arranged at the bottom of the inner cavity of the buffer feeding assembly 300; A spiral feeding frame 330 is rotatably arranged in the inner cavity of the buffer feeding assembly 300, which is used to slow down the falling speed of coffee and make it evenly distributed on the surface of the filtering assembly 400. The filtering assembly 400 is used to intercept macromolecular impurities and permeate small molecular flavor substances; A scraper 3301 is arranged at the bottom of the spiral feeding frame 330. When the coffee liquid flows into the buffer feeding assembly 300, the liquid contacts the spiral structure of the spiral feeding frame 330 to generate a tangential component force, driving the spiral feeding frame 330 to rotate, and at the same time driving the scraper 3301 to scrape the surface of the filtering assembly 400; A vacuum pump 110 is fixedly connected and communicated to the surface of the concentration cavity 100. A stirring assembly 200 is arranged in the inner cavity of the concentration cavity 100. The rotation of the spiral feeding frame 330 synchronously drives the stirring assembly 200 to rotate in the inner cavity of the concentration cavity 100 to uniformly mix the coffee liquid in the inner cavity of the concentration cavity 100.

[0014] The vacuum pump 110 sucks the gas in the inner cavity of the concentration cavity 100 to quickly discharge it, reducing the pressure in the concentration cavity 100 to form a negative pressure environment; When the coffee liquid is poured into the buffer feeding assembly 300, After the coffee liquid enters the buffer feeding component 300, the driving component 500 drives the spiral feeding frame 330 to rotate. The rotational movement of the spiral structure causes the coffee liquid to be affected by the combined action of centrifugal force and gravity and slowly fall along the spiral trajectory, avoiding direct impact on the filtering component 400. At the same time, the uniform distribution design of the spiral feeding frame 330 enables the coffee liquid to be laid flat on the surface of the filtering component 400 in the form of a thin layer, ensuring the filtering uniformity; Considering that in the filtering process, generally, the coffee liquid is directly poured into the interior of the box and filtered naturally by gravity. At this time, impurities such as suspended particles and colloids in the coffee liquid are extremely likely to penetrate the filtering holes of the filter screen and flow out directly under the action of gravity, affecting the clarity and purity of the concentrated liquid. Therefore, when the coffee stock solution enters the inner cavity of the buffer feeding component 300, the liquid will contact the surface of the spiral structure of the spiral feeding frame 330. The coffee liquid flows along the spiral blade and applies a tangential thrust to the spiral surface, forming a rotational torque. At this time, the driving component 500 provides auxiliary power to further enhance the rotational stability of the spiral feeding frame 330, enabling the coffee liquid to be evenly spread on the surface of the filtering component 400 at a controllable flow rate, avoiding local concentrated impact resulting in impurities penetrating the filter screen. At the same time, the scraper 3301 fixed at the bottom of the spiral feeding frame 330 continuously scrapes the surface of the filtering component 400 during rotation, timely removing the deposited impurities and preventing the filter holes from being blocked, ensuring the long-term stability of the filtering efficiency.

[0015] At the same time, considering existing equipment, generally, stirring is carried out after the filtering is completed. At this time, some small molecular particles after filtering will precipitate at the bottom of the inner cavity of the concentration cavity 100. Therefore, the operation of the driving component 500 will synchronously drive the rotation of the spiral feeding frame 330 and synchronously drive the stirring component 200 to rotate in the inner cavity of the concentration cavity 100. In this way, stirring can be carried out immediately after the coffee liquid enters the concentration cavity 100, which can quickly break the local non-uniformity caused by raw material addition, concentration difference, etc., enabling the aromatic substances, sugars, acidic components, etc. in the coffee liquid to be fully integrated, reducing the precipitation or stratification of some components in the coffee liquid in the static state, which affects the concentration effect and product stability.

[0016] On the above basis, the specific structure is disclosed in detail: In order to enable the vacuum pump 110 connected to the surface of the concentration cavity 100 to form a negative pressure during operation and concentrate the coffee liquid, a jacket 102 is provided in the inner cavity of the concentration cavity 100, a water inlet pipe 1021 is provided on the surface of the concentration cavity 100, a water outlet pipe 1022 is provided on the surface of the concentration cavity 100, and the water inlet pipe 1021 and the water outlet pipe 1022 are connected to the jacket 102; The jacket 102 is arranged around the inner wall of the concentration cavity 100 for one week; Low-temperature water flows into the inner cavity of the jacket 102 through the water inlet pipe 1021, forming a heat conduction channel surrounding the concentration cavity 100. The vacuum pump 110 extracts the air in the concentration cavity 100 to form a negative pressure environment. Under low pressure, the boiling point of the liquid will decrease significantly. For example, the boiling point of water is 100°C under standard atmospheric pressure, while at a vacuum degree of 0.09 MPa, the boiling point of water can drop to about 70°C or below. The water in the coffee liquid is more likely to vaporize under negative pressure, and the vaporization process will absorb heat, resulting in a decrease in the temperature of the coffee liquid. By reducing the boiling point through vacuum, concentration can be achieved at a relatively low temperature, such as 20 - 30°C, avoiding the destruction of aromatic substances in coffee due to high temperature.

[0017] Any solvent water in a solution, such as an aqueous solution, will diffuse into the air through evaporation, and its evaporation rate is directly related to the vapor pressure of the solution. When low-temperature water at 20 - 30°C comes into contact with the solution to be concentrated or through heat exchange, if the environmental pressure of the low-temperature water is low enough, such as in a vacuum environment, the water molecules in the solution will migrate to the low-temperature water or the gas phase due to the vapor pressure difference, thus realizing the separation of the solvent water and achieving the purpose of concentration.

[0018] The water inlet pipe 1021 is located on the upper surface of the concentration cavity 100, and the water outlet pipe 1022 is located on the lower surface of the concentration cavity 100, forming a flow path for low-temperature water to flow downward in the jacket 102. A temperature sensor is fixedly connected to the surface of the concentration cavity 100. Low-temperature water at 20 - 30°C enters the jacket 102 from the water inlet pipe 1021 and uniformly flows downward along the inner wall of the jacket 102 under the action of gravity. It exchanges heat with the coffee liquid in the inner cavity of the concentration cavity 100 through the inner side wall of the jacket 102, and finally discharges from the water outlet pipe 1022. The temperature sensor will continuously detect the temperature of the original coffee liquid in the concentration cavity 100 to ensure that it is always within a suitable range.

[0019] In order for the buffer feeding component 300 to receive the coffee liquid, it is necessary to further disclose the parts of the buffer feeding component 300. Therefore, a feeding device 320 is fixedly connected to the surface of the spiral feeding rack 330, and an annular fixing rack 310 is fixedly connected to the surface of the feeding device 320. The annular fixing rack 310 is fixed on the surface of the concentration cavity 100. An inlet is provided at the top of the feeding device 320. The feeding device 320 is located above the concentration cavity 100, and a feeding pipe 340 is fixedly connected to the bottom of the feeding device 320. The end of the feeding pipe 340 communicates with the inner cavity of the concentration cavity 100. The original coffee liquid is poured into the inner cavity of the feeding device 320 from the inlet. At this time, the liquid will contact the spiral structure surface of the spiral feeding rack 330, generating a tangential thrust to drive its rotation. At the same time, the driving component 500 will assist in driving the spiral feeding rack 330 to rotate. The rotating spiral feeding rack 330 drives the scraper 3301 to scrape the surface of the filtering component 400. The buffered coffee liquid enters the concentration cavity 100 through the feeding pipe 340 and is stirred and mixed evenly by the stirring component 200.

[0020] In order for the spiral feeding rack 330 to rotate in cooperation with the coffee liquid, therefore, a rotating shaft 3202 is rotatably connected to the top of the inner cavity of the feeding device 320 through a bearing. A transmission gear meshing with the output gear of the driving component 500 is provided on the outer circumference of the rotating shaft 3202. The spiral feeding rack 330 has an inclined downward spiral structure and is fixedly wound around the surface of the rotating shaft 3202, and the spiral angle is designed to be 30°-45° to ensure that the coffee liquid can flow along the spiral track and generate a tangential thrust. The coffee liquid is poured into the feeding device 320 from the inlet at the top. When the liquid flows along the inclined spiral track of the spiral feeding rack 330, a tangential thrust is applied to the spiral surface, forming a rotating moment, and this moment drives the spiral feeding rack 330 to drive the rotating shaft 3202 to rotate in the inner cavity of the feeding device 320.

[0021] In order for the spiral feeding rack 330 to remain stable when rotating in the inner cavity of the feeding device 320, therefore, an annular limiting groove 3201 is provided on the inner wall of the feeding device 320, and a slider 3302 is fixedly connected to the surface of the spiral feeding rack 330. The surface of the slider 3302 slides on the inner wall of the annular limiting groove 3201; The annular limiting groove 3201 is annularly provided around the inner wall of the feeding device 320. When the coffee liquid flows along the spiral feeding rack 330, a tangential thrust is generated to drive the spiral feeding rack 330 to rotate. The driving component 500 will assist in driving the spiral feeding rack 330 to rotate at the same time. At this time, the slider 3302 slides along the track of the annular limiting groove 3201, restricting the rotation position of the spiral feeding rack 330 to ensure a stable rotation trajectory. The rotating shaft 3202 bears the main axial load. The annular limiting groove 3201 cooperates with the slider 3302 to prevent the spiral feeding rack 330 from swinging or eccentrically rotating.

[0022] In order for the filtration component 400 to retain large-particle impurities on its surface and allow small molecules that retain the fragrance to flow into the inner cavity of the concentration cavity 100, it is necessary to further disclose the parts of the filtration component 400. Therefore, the filtration component 400 is made to include a filtration bracket 410 fixedly connected to the inner wall of the feeding device 320. The inner wall of the filtration bracket 410 includes an upper microfiltration membrane 4101 and a lower precision filtration membrane 4102; The upper microfiltration membrane 4101 is used to intercept visible suspended matters such as coffee grounds to prevent clogging of the lower precision filtration membrane 4102; The lower precision filtration membrane 4102 is used to selectively retain macromolecules while allowing small molecule aroma components to pass through; The upper microfiltration membrane 4101 is used to intercept large-particle impurities, and the lower precision filtration membrane 4102 selectively retains macromolecular substances while allowing small molecule aroma components to pass through, which can effectively improve the purity of the coffee concentrate and retain the aroma components of the coffee.

[0023] The filtration bracket 410 is vertically installed directly below the spiral feeding rack 330, and the surface of the scraper 3301 slides on the surface of the upper microfiltration membrane 4101, and the bottom of the filtration bracket 410 is suspended, leaving a space with the bottom of the inner cavity of the feeding device 320; the coffee liquid is evenly spread on the surface of the lower upper microfiltration membrane 4101 along the spiral of the spiral feeding rack 330. Since the filtration bracket 410 is vertically installed directly below the spiral feeding rack 330, the liquid falling path is short and concentrated, which can reduce splashing. The upper microfiltration membrane 4101 intercepts large-particle impurities in the coffee liquid. When the spiral feeding rack 330 rotates, the scraper 3301 fixed to its bottom rotates synchronously with the shaft and slides closely on the surface of the upper microfiltration membrane 4101 to timely remove impurities such as coffee residues and fibers attached to the membrane surface to prevent the filter holes from being blocked by particle accumulation. The bottom of the filtration bracket 410 is suspended, forming a space with the bottom of the inner cavity of the feeding device 320 for penetration.

[0024] Considering that when the vacuum pump 110 adsorbs the air in the inner cavity of the concentration cavity 100, it is necessary to make the equipment in a sealed state. Therefore, a chute 3203 is provided at the top of the feeding device 320, and a rotating plate 3204 is slidably connected to the inner wall of the chute 3203; when the equipment is running, manually move the rotating plate 3204 to slide along the chute 3203 so that its bottom fits on the surface of the feed port to seal the equipment. And during this process, the residual coffee liquid in the spiral feeding rack 330 will continuously drive the rotating shaft 3202 to rotate, so that the stirring component 200 continuously mixes and stirs the coffee liquid entering the inner cavity of the concentration cavity 100.

[0025] The coffee liquid passing through the filter screen can fall to the bottom of the feeding device 320 under the action of gravity and flow into the concentration cavity 100 through the feed pipe 340, avoiding the retention of the filtrate below the filtration bracket 410 or the formation of a dead water area.

[0026] In order to enable the stirring assembly 200 to rotate in cooperation with the spiral feeding rack 330, it is necessary to further disclose the parts of the stirring assembly 200. Therefore, a rotating shaft 210 is rotatably connected to the inner cavity of the concentration cavity 100 by means of a bearing. The end of the rotating shaft 3202 penetrates the bottom of the feeding device 320 and is fixedly connected to the rotating shaft 210. A stirring rod 220 is fixedly connected to the surface of the rotating shaft 210; A discharge pipe 101 is fixedly communicated with the bottom of the concentration cavity 100; when the driving assembly 500 works, it drives the spiral feeding rack 330 to rotate and simultaneously drives the rotating shaft 3202 to rotate. At this time, the rotating shaft 210 will follow the rotation of the rotating shaft 3202 to stir the coffee liquid entering the inner cavity of the concentration cavity 100.

[0027] In summary, the working process of the present invention is as follows: The coffee concentrate is poured into the buffer feeding assembly 300 through the feeding port at the top of the feeding device 320, directly contacting the spiral feeding rack 330 surrounding the surface of the rotating shaft 3202. At this time, the spiral structure on the surface of the spiral feeding rack 330 guides the liquid to flow downward along the spiral track. When the coffee liquid flows along the spiral surface, gravity is decomposed into an axial component force to push the liquid downward and a tangential component force, and the tangential component force forms a rotating torque. At this time, the driving assembly 500 will assist in driving the rotation of the rotating shaft 3202 at the same time. The rotating shaft 3202 rotates in the inner cavity of the feeding device 320 through the top bearing. The rotating spiral feeding rack 330 evenly spreads the coffee liquid on the surface of the upper microfiltration membrane 4101 below at a low speed. After the filtrate penetrates through the upper microfiltration membrane 4101, it enters the lower precision filtration membrane 4102, selectively intercepting macromolecules such as proteins and colloids, and at the same time allowing small molecules such as caffeine and aromatic substances to pass through, improving the purity and flavor retention rate of the concentrated liquid. The scraper 3301 fixed to the bottom of the spiral feeding rack 330 rotates synchronously with the spiral feeding rack 330, and its surface slides closely against the upper microfiltration membrane 4101, continuously scraping off the attached impurities to avoid clogging of the filter holes. The bottom of the filter support 410 is suspended, forming a space with the bottom of the inner cavity of the feeding device 320. The permeated coffee liquid falls to the bottom of the feeding device 320 under the action of gravity and flows into the concentration cavity 100 through the feeding pipe 340. The lower end of the rotating shaft 3202 penetrates the bottom of the feeding device 320 and is fixedly connected to the rotating shaft 210 in the concentration cavity 100. When the spiral feeding rack 330 rotates, it synchronously drives the rotation of the rotating shaft 210 and the stirring rod 220 on its surface, radially stirring the coffee liquid flowing into the concentration cavity to break the concentration stratification and promote the uniform distribution of aromatic substances. Manually move the rotating plate 3204 to slide along the chute 3203 so that its bottom fits on the surface of the feeding port to seal the device. And during this process, the residual coffee liquid in the spiral feeding rack 330 will continuously drive the rotation of the rotating shaft 3202, so that the stirring assembly 200 continuously mixes and stirs the coffee liquid entering the inner cavity of the concentration cavity 100. The vacuum pump 110 extracts the air in the concentration cavity 100 to form a negative pressure environment, reducing the boiling point of the coffee liquid to avoid destroying flavor substances at high temperature. The low-temperature water at 20 - 30°C flows unidirectionally from top to bottom into the jacket 102 and flows around the inner wall of the cavity, transferring heat to the coffee liquid through heat conduction to compensate for the heat required for water vaporization and maintaining the stability of the concentration temperature. The coffee liquid after concentration will flow out from the discharge port at the bottom.

[0028] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only preferred examples of the present invention and are not used to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A low-temperature vacuum concentration device for coffee cold extraction liquid, comprising a concentration cavity (100), wherein a support frame (120) is fixedly connected to the surface of the concentration cavity (100), and is characterized in that: A buffer feeding component (300) is fixedly connected to the top of the concentration cavity (100), and a filtering component (400) is arranged at the bottom of the inner cavity of the buffer feeding component (300); A spiral feeding frame (330) is rotatably arranged in the inner cavity of the buffer feeding component (300) for slowing down the falling speed of coffee and making it evenly distributed on the surface of the filtering component (400), and the filtering component (400) is used for intercepting macromolecular impurities and permeating small molecular flavor substances; A vacuum pump (110) is fixedly communicated with the outer wall of the concentration cavity (100), a stirring component (200) is arranged in its inner cavity, and a driving component (500) is fixedly connected to the top of the concentration cavity (100). The driving component (500) simultaneously drives the spiral feeding frame (330) to rotate and drives the stirring component (200) to rotate in the concentration cavity (100) to realize the uniform mixing of coffee liquid; A scraper (3301) is arranged at the bottom of the spiral feeding frame (330). When the driving component (500) drives the spiral feeding frame (330) to rotate, the scraper (3301) scrapes the surface of the filtering component (400) to prevent impurities from blocking the filtering component (400).

2. The low-temperature vacuum concentration equipment for cold-brewed coffee liquid according to claim 1, wherein: A jacket (102) is arranged in the inner cavity of the concentration cavity (100), a water inlet pipe (1021) is arranged on the surface of the concentration cavity (100), a water outlet pipe (1022) is arranged on the surface of the concentration cavity (100), and the water inlet pipe (1021) and the water outlet pipe (1022) are communicated with the jacket (102); The jacket (102) is arranged around the inner wall of the concentration cavity (100) for one week.

3. The low-temperature vacuum concentration equipment for cold-brewed coffee liquid according to claim 2, wherein: The water inlet pipe (1021) is located on the upper surface of the concentration cavity (100), and the water outlet pipe (1022) is located on the lower surface of the concentration cavity (100), forming a circulation path of low-temperature water flowing from top to bottom in the jacket (102); A temperature sensor is fixedly connected to the surface of the concentration cavity (100).

4. The low-temperature vacuum concentration equipment for cold-brewed coffee liquid according to claim 1, wherein: A feeding device (320) is fixedly connected to the surface of the spiral feeding frame (330). An annular fixing frame (310) is fixedly connected to the surface of the feeding device (320). The annular fixing frame (310) is fixed on the surface of the concentration cavity (100). A feeding port is arranged at the top of the feeding device (320). The feeding device (320) is located above the concentration cavity (100), and a feeding pipe (340) is fixedly connected to the bottom of the feeding device (320). The end of the feeding pipe (340) is communicated with the inner cavity of the concentration cavity (100).

5. The low-temperature vacuum concentration equipment for cold-brewed coffee liquid according to claim 4, wherein: A rotating shaft (3202) is rotatably connected to the top of the inner cavity of the feeding device (320) through a bearing. A transmission gear meshing with the output gear of the driving component (500) is arranged on the outer circumference of the rotating shaft (3202). The spiral feeding frame (330) is in an inclined downward spiral structure and is fixedly arranged around the surface of the rotating shaft (3202).

6. The low-temperature vacuum concentration equipment for cold-brewed coffee liquid according to claim 4, characterized in that: The inner wall of the blanking device (320) is provided with an annular limiting groove (3201), and a slider (3302) is fixedly connected to the surface of the spiral blanking frame (330), and the surface of the slider (3302) slides on the inner wall of the annular limiting groove (3201); The annular limiting groove (3201) is annularly formed around the inner wall of the blanking device (320).

7. The low-temperature vacuum concentration equipment for cold-brewed coffee liquid according to claim 4, wherein: The filtering assembly (400) includes a filtering support (410) fixedly connected to the inner wall of the blanking device (320), and the inner wall of the filtering support (410) includes an upper microfiltration membrane (4101) and a lower precision filtration membrane (4102); The upper microfiltration membrane (4101) is used to intercept visible suspended matters such as coffee powder residues to prevent blocking the lower precision filtration membrane (4102); The lower precision filtration membrane (4102) is used to selectively retain macromolecules while allowing small molecule aroma components to pass through.

8. The low-temperature vacuum concentration equipment for cold-brewed coffee liquid according to claim 7, characterized in that: The filtering support (410) is vertically installed directly below the spiral blanking frame (330), and the surface of the scraper (3301) slides on the surface of the upper microfiltration membrane (4101), and the bottom of the filtering support (410) is suspended, leaving a space from the bottom of the inner cavity of the blanking device (320).

9. The low-temperature vacuum concentration equipment for cold-brewed coffee liquid according to claim 4, wherein: A chute (3203) is provided at the top of the blanking device (320), and a rotating plate (3204) is slidably connected to the inner wall of the chute (3203).

10. The low-temperature vacuum concentration equipment for cold-brewed coffee liquid according to claim 5, characterized in that: A rotating shaft (210) is rotatably connected to the inner cavity of the concentration chamber (100) by means of a bearing. The end of the rotating shaft (3202) penetrates through the bottom of the blanking device (320) and is fixedly connected to the rotating shaft (210), and a stirring rod (220) is fixedly connected to the surface of the rotating shaft (210); The bottom of the concentration chamber (100) is fixedly communicated with a discharge pipe (101).

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