Low-temperature crushing method for preventing flavor deterioration of coffee

Abstract

The invention discloses a low-temperature crushing method for preventing coffee flavor deterioration, relates to the technical field of food processing and coffee processing, and is based on cooperative control of a rotor, an inert gas circulation loop, an annular injection nozzle, a purification unit, a phase change temperature limiting assembly and an aroma temporary storage and recharge branch. The method comprises the following steps: S1, acquiring rotating speed and power to calculate a stability index of a river guard, locking an outward discharge boundary and forming annular sheath laminar flow; s2, parameters of a circulating power part are collected to obtain a purification load index, a temperature rise platform index is obtained through power accumulation, smashing is conducted according to a temperature limiting track, and main purification / bypass is distributed in a self-adaptive mode; s3, triggering the adsorption sheet to desorb according to an aroma residence window index, and refilling the aroma into a powder outlet mainstream area; and S4, keeping inert powder discharge. And the swept flow of the sealing gap is discharged outwards from inside to outside.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of food processing and coffee processing, and particularly relates to a low-temperature crushing method for preventing deterioration of coffee flavor. BACKGROUND

[0002] During the crushing process of coffee, the specific surface area increases rapidly, the contact interface between the powder and the gas increases significantly, and the friction heat generated by crushing causes local temperature rise, thereby accelerating the escape of volatile flavor substances and the occurrence of oxidation reaction, and further causing the decrease of aroma and the weakening of flavor, and even the appearance of unpleasant odor. In addition, the crushing device usually has structure boundaries such as powder outlet channel and sealing gap, and the exhaust and backflow of the crushing cavity are prone to pressure fluctuation under different working conditions. External air may flow back into the crushing cavity or the powder outlet area through the sealing gap, so that the powder is exposed to an oxygen-containing environment during the crushing and powdering stages, further aggravating the deterioration of flavor.

[0003] In order to reduce the above deterioration risk, the following measures are usually adopted in the prior art: reducing the crushing temperature or pre-cooling the raw materials to reduce the temperature rise caused by friction heat; flushing inert gas into the crushing cavity or the powder outlet area to reduce the oxygen content; setting oxygen and water removal devices to purify the circulating gas to obtain an atmosphere with low oxygen content and low dew point; and reducing the probability of external air entering by improving the sealing structure or setting an exhaust system.

[0004] However, the above prior art still has certain limitations. Specifically, although the prior art can reduce the temperature rise or the oxygen content to a certain extent, the following deficiencies may still occur in actual operation: when relying only on pre-cooling or simple inert gas flushing, the crushing efficiency and temperature rise suppression cannot be considered simultaneously, and the transient friction heat during crushing may still cause temperature rise peaks; the sealing gap of the crushing device is prone to change in backflow direction under different flow rates and pressure differentials, and external air may still flow back when the outward sweeping flow is unstable, especially during backflow and powdering stages; the purification unit is prone to problems such as increased pressure loss in the loop, unstable circulation under high flow conditions, and difficulty in balancing oxygen and water removal depth and loop supply and discharge under low flow conditions, making it difficult to continuously and stably obtain low-oxygen and low-dew-point conditions; most schemes only focus on temperature reduction or inert protection, and lack a mechanism for capturing and backflowing volatile flavor substances carried by the gas flow, making it difficult to achieve aroma reattachment on the surface of the crushed powder; some schemes often need to additionally configure sensors such as temperature, oxygen content, pressure, and flow rate, and actuators such as electric control valves, in order to achieve temperature control, atmosphere control, and state switching, which increases the system complexity and cost, and lacks adaptability and reproducibility for different devices.

[0005] Therefore, there is an urgent need for a low-temperature grinding method to prevent coffee flavor degradation. This method should be able to stabilize the outward flow of laminar flow through a sealed gap and suppress backflow of external air without introducing new sensor data or actuator control. It should be based on the coordinated scheduling of a rotor, an inert gas circulation loop, an annular ejector nozzle, a purification unit, an annular phase change temperature limiting component, and an aroma storage and recirculation branch. This would reduce the risk of flavor degradation during the coffee grinding process and improve the product's flavor retention. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and propose a low-temperature pulverization method for preventing the deterioration of coffee flavor, so as to solve the above-mentioned problems.

[0007] The objective of this invention is achieved through the following technical solution: a low-temperature grinding method for preventing coffee flavor deterioration, based on the coordinated scheduling of the rotor, inert gas circulation loop, annular ejector nozzle, purification unit, annular phase change temperature limiting component, and aroma temporary storage and recirculation branch of a low-temperature grinding device, the method comprising: S1 boundary locking collects rotor speed and rotor drive power and generates moat stability index accordingly. It controls the rotor speed to increase along the boundary locking speed trajectory to the boundary locking speed range and maintains it until the moat stability index reaches the boundary locking threshold. This causes the sweeping jet formed by the rotor exhaust to generate ejector negative pressure at the throat of the annular ejector nozzle and draws inert gas from the exhaust end of the purification unit through the ejector intake port. This causes the inert gas to form an annular sheath laminar flow from the annular nozzle outlet along the sealing gap, thereby locking the loop boundary of the inert gas circulation loop as an outward release boundary. The annular sheath laminar flow continuity is maintained through the throttling branch between the gas supply section and the ejector gas supply manifold so that the sweeping flow direction at the sealing gap remains from inside the cavity to outside the cavity. The S2 aroma-catching and pulverizing unit collects the rotational speed and driving power of the circulating power component and generates a purification load index accordingly. It also generates a temperature rise plateau index based on the time accumulation of the rotor driving power. The rotor speed is controlled to change according to the fine-tuning rules along the temperature-limited pulverizing speed trajectory within the temperature-limited pulverizing speed range so that the annular phase change temperature-limiting component absorbs peak frictional heat through the directional thermal channel and keeps the temperature rise plateau index within the temperature-limited plateau range. At the same time, under the condition that the loop boundary is locked as the outward discharge boundary and the purification load index does not exceed the purification load threshold, the porous inert adsorption sheet of the aroma temporary storage and reinjection branch adsorbs and temporarily stores the volatile flavor substances carried by the inert gas in the low-temperature stage of the same thermal coupling link as the annular phase change temperature-limiting component. The purification unit adaptively allocates the main purification channel and the bypass channel under the action of the differential pressure valve. S3 recharge triggers the rotor speed to decrease from the temperature-limited pulverizing speed range to the recharge trigger speed range along the recharge trigger speed trajectory and maintain it until the aroma retention window index generated based on the temperature rise plateau index and the rotor speed trajectory switches from the adsorption window to the desorption window. This causes the porous inert adsorption sheet to desorb during the temperature rise phase of the outer wall of the chamber and injects the desorbed volatile flavor substances into the mainstream powder area of ​​the powder outlet channel through the recharge guide pipe. This allows the powder to be recharged and adsorbed onto the powder surface under the inert atmosphere supplied by the gas outlet of the purification unit. During the recharge process, when the moat stability index is lower than the maintenance threshold, the rotation speed trajectory of the circulating power component is increased and the baseline gas supply pressure difference is provided by the throttling branch to maintain the laminar flow continuity of the annular sheath. S4 inertial powder discharge maintenance controls the rotor speed to enter the powder discharge maintenance speed range along the powder discharge maintenance speed trajectory and maintain the powder discharge maintenance time, so that the air supply port and the annular ejector nozzle are continuously supplied with inert gas after deoxygenation and dehydration from the air outlet of the purification unit, so as to complete the inert powder discharge and make the aroma retention window index enter the refill completion window.

[0008] The control output of the coordinated scheduling only includes the rotor speed trajectory and the circulating power component speed trajectory. The moat stability index, purification load index, temperature rise plateau index, and aroma residence window index are generated only by the rotor speed, rotor drive power, circulating power component speed, circulating power component drive power, and running time. The rotor speed and rotor drive power are read from the operating parameters output by the rotor driver, and the circulating power component speed and circulating power component drive power are read from the operating parameters output by the circulating power component driver. Therefore, no new sensor data acquisition or new actuator control data is introduced in the entire process.

[0009] The moat stability index is determined by the combination of rotor speed and rotor drive power to characterize the suction intensity of the annular ejector nozzle on the inert gas at the outlet of the purification unit and the stability of the sweep flow direction of the sealing gap. The boundary locking threshold corresponds to limiting the minimum suction intensity at the sealing gap to maintain the sweep flow direction from inside the cavity to outside the cavity.

[0010] The temperature rise plateau index is determined by the combination of the equivalent energy accumulation of rotor drive power over time and the calibration parameters of the heat absorption capacity of the annular phase change temperature limiting component. This is used to characterize the degree to which the annular phase change temperature limiting component is in a heat absorption plateau state. The fine-tuning rules for the temperature limiting crushing speed trajectory include segmented maintenance and segmented ramp changes of the rotor speed to keep the temperature rise plateau index within the temperature limiting plateau range and suppress the temperature rise peak of the outer wall of the cavity.

[0011] The purification load index is determined by the combination of the rotation speed of the circulating power component, the driving power of the circulating power component, and the running time. It characterizes the load margin of the solid phase deoxygenation bed and the solid phase dehydration bed of the purification unit. The purification load threshold corresponds to the minimum margin required to maintain the deoxygenation and dehydration depth at the outlet of the purification unit.

[0012] The adaptive allocation of the main purification channel and the bypass channel by the purification unit is achieved by the displacement of the differential pressure valve plate under the pressure difference between the main purification channel and the bypass channel, resulting in a change in opening degree. The adaptive allocation process does not use an electronically controlled valve to participate in the allocation. The adaptive allocation is used to reduce the pressure loss of the loop under high flow conditions to maintain the powder output cycle and to increase the proportion of the main purification channel under low flow conditions to improve the deoxygenation and dehydration depth, thereby meeting the low oxygen and low dew point conditions of the adsorption and temporary storage stage of the porous inert adsorption sheet.

[0013] The aroma retention window index is determined by the combination of the temperature rise plateau index and the rotor speed trajectory to characterize the working state of the porous inert adsorption sheet in the same thermal coupling link as the annular phase change temperature limiting component. It is configured to switch continuously in the order of adsorption window, desorption window, and recharge completion window, with the appearance of the desorption window as a necessary condition for entering the recharge trigger and the appearance of the recharge completion window as a necessary condition for exiting the recharge trigger.

[0014] The coordinated scheduling involves pre-storing the moat stability index threshold, purification load index threshold, temperature rise platform index platform interval, and aroma retention window index window sequence as a set of state transition conditions and a set of rotation speed corridors. Then, it generates boundary locking rotation speed trajectory, temperature limiting pulverization rotation speed trajectory, recharge triggering rotation speed trajectory, and powder output maintaining rotation speed trajectory using deterministic rules that only include comparison operations and table lookup operations, thereby forming the necessary state sequence from S1 to S4.

[0015] The entry conditions for capturing and crushing incense include the moat stability index reaching the boundary locking threshold and the purification load index not exceeding the purification load threshold. The entry conditions for triggering recharge include the capture duration reaching the capture threshold and the temperature rise plateau index being in the temperature limit plateau range. During the recharge triggering period, the moat stability index is continuously constrained to not be lower than the maintenance threshold.

[0016] Before executing S1, the method includes reading the rotor speed, rotor drive power, and circulating power unit speed and driving power from the rotor driver and circulating power unit driver under no-feeding conditions, and completing baseline acquisition. Based on the baseline acquisition results, the threshold values ​​of the moat stability index, the purification load index, and the temperature rise plateau index are calibrated to eliminate the influence of device differences on the set of state transition conditions. When the moat stability index generated based on the rotor speed and rotor drive power is lower than the maintenance threshold during S2 or S3, the circulating power unit speed trajectory is increased and the baseline gas supply pressure difference is provided by the throttling branch to maintain the laminar flow continuity of the annular sheath. When the moat stability index is still lower than the maintenance threshold, the rotor speed trajectory is switched to the powder outlet maintenance speed trajectory and the gas supply port is supplied with inert gas from the gas outlet of the purification unit to maintain the loop boundary as an outward venting boundary.

[0017] The beneficial effects of this invention are: The rotor, inert gas circulation loop, annular ejector nozzle, purification unit, annular phase change temperature limiting component, and aroma storage and reinjection branch of the cryogenic pulverizing device are coordinated and scheduled. The rotor speed and rotor drive power are collected by the S1 boundary locking to generate the moat stability index and control the rotor speed to enter the boundary locking speed range along the boundary locking speed trajectory. The sweeping jet formed by the rotor exhaust generates ejection negative pressure at the throat of the annular ejector nozzle and draws inert gas from the outlet of the purification unit through the ejector intake port. From the annular nozzle outlet, an annular sheath laminar flow is formed along the sealing gap to lock the loop boundary of the inert gas circulation loop as an outward venting boundary. The continuity of the annular sheath laminar flow is maintained by the throttling branch between the gas supply section and the ejector gas supply manifold. The sweeping flow direction at the sealing gap is kept from inside the cavity to outside the cavity. Thus, during the entire pulverizing process, the backflow of outside air into the pulverizing cavity through the sealing gap is suppressed and the risk of oxidation and deterioration caused by the oxygen-containing environment is reduced.

[0018] In the S2 aroma-catching and pulverizing process, the rotational speed and driving power of the circulating power component are collected to generate a purification load index. Based on the time accumulation of the rotor driving power, a temperature rise plateau index is generated. The rotor speed is controlled to vary along the temperature-limited pulverizing speed trajectory within the temperature-limited pulverizing speed range according to a fine-tuning rule. This allows the annular phase-change temperature-limiting component to absorb peak frictional heat through directional thermal channels and keeps the temperature rise plateau index within the temperature-limited plateau range. This suppresses temperature rise spikes on the outer wall of the chamber and reduces the possibility of volatile flavor substances escaping due to heat. Simultaneously, the loop boundary is locked as an outward venting boundary, and the purification... Under the condition that the chemical load index does not exceed the purification load threshold, the porous inert adsorption plate of the aroma temporary storage and reinjection branch adsorbs and temporarily stores the volatile flavor substances carried by the inert gas in the low-temperature stage of the same thermal coupling link as the annular phase change temperature limiting component. The purification unit adaptively allocates the main purification channel and the bypass channel under the action of the differential pressure valve plate, so as to reduce the loop pressure loss under high flow conditions and improve the deoxygenation and dehydration depth under low flow conditions. Thus, without introducing an electronically controlled valve to participate in the allocation, both circulation stability and purification depth are taken into account, and the stability and availability of inert atmosphere are improved.

[0019] In the S3 recharge triggering process, the rotor speed is controlled to decrease from the temperature-limited pulverizing speed range to the recharge triggering speed range along the recharge triggering speed trajectory. Based on the temperature rise plateau index and the rotor speed trajectory, an aroma retention window index is generated, causing it to switch from the adsorption window to the desorption window. This allows the porous inert adsorption sheet to desorb during the temperature rise phase of the outer wall of the chamber, and the desorbed volatile flavor substances are injected into the mainstream powder area of ​​the powder outlet channel through the recharge guide pipe. Recharge is completed under the inert atmosphere supplied by the gas outlet of the purification unit, and the substances are adsorbed on the powder surface to reduce aroma loss and improve the flavor retention of the finished powder. Furthermore, when the moat stability index is lower than the maintenance threshold during the recharge process, the rotation speed trajectory of the circulating power component is increased and the baseline gas supply pressure difference is provided by the throttling branch to maintain the laminar flow continuity of the annular sheath. This ensures that the outward sweeping flow direction does not reverse within the recharge window, improving the reliability of the recharge process.

[0020] In the S4 inert powder discharge holding process, the rotor speed is controlled to enter the powder discharge holding speed range along the powder discharge holding speed trajectory and maintain the powder discharge holding time. This ensures that the air supply port and the annular ejector nozzle are continuously supplied with inert gas after deoxygenation and dehydration from the air outlet of the purification unit, and the outward sweeping flow direction is kept from reversing to complete the inert powder discharge. In this way, the inert atmosphere is maintained during the powder discharge stage, and the risk of re-oxidation of the powder during the discharge process is reduced. This ensures the consistency of the process and the stability of the product when the aroma retention window index enters the refill completion window.

[0021] The collaborative scheduling control output includes only the rotor speed trajectory and the circulating power component speed trajectory. The moat stability index, purification load index, temperature rise plateau index, and aroma retention window index are generated only by the rotor speed, rotor drive power, circulating power component speed, circulating power component drive power, and running time. Thus, no new sensor data acquisition or actuator control data is introduced in the entire process. Thresholds, plateau intervals, and window sequences can be pre-stored as a set of state transition conditions and a set of speed corridors. Deterministic rules containing only comparison operations and table lookup operations are used to generate boundary locking speed trajectories, temperature-limited pulverizing speed trajectories, recharge triggering speed trajectories, and powder discharge holding speed trajectories. This makes S1 to S4 a necessary state sequence, improving the reproducibility, verifiability, and engineering adaptability of the implementation. Attached Figure Description

[0022] Figure 1 The process of this invention Figure 1 ; Figure 2 The process of this invention Figure 2 ; Figure 3 The process of this invention Figure 3 . Detailed Implementation

[0023] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1 like Figure 1 As shown, this embodiment is based on the coordinated scheduling of the rotor of the low-temperature pulverizing device, the inert gas circulation loop, the annular ejector nozzle, the purification unit, the annular phase change temperature limiting component, and the aroma temporary storage and refill branch, so as to maintain an inert atmosphere and suppress temperature rise peaks throughout the entire process of pulverizing, aroma capture, refilling, and powder discharge, thereby reducing the escape and oxidation of volatile flavor substances.

[0025] The cryogenic pulverizing device described in this embodiment includes: a pulverizing chamber and a rotor assembly, the rotor being driven by a rotor driver; an inert gas circulation loop, including a gas supply section, a return section, a circulation power component, and a throttling branch between the gas supply section and the ejector gas supply manifold; an annular ejector nozzle, having a throat, an ejector intake port, and an annular ejector outlet arranged along a sealing gap; a purification unit, having a main purification channel and a bypass channel, wherein a solid-phase deoxygenation bed and a solid-phase dehydration bed are sequentially arranged in the main purification channel, and a differential pressure valve is arranged between the main purification channel and the bypass channel to form an adaptive distribution under the action of pressure difference; an annular phase change temperature limiting component, surrounding or attached to the pulverizing chamber and forming a thermal coupling link with the pulverizing chamber through a directional thermal channel; and an aroma temporary storage and recharge branch, including a porous inert adsorption sheet and a recharge guide pipe, the outlet of which is connected to the main powder flow zone of the powder outlet channel.

[0026] In this embodiment, the inert gas is preferably nitrogen or argon, and the inert gas circulation loop is a closed loop that allows controlled outward release when the loop boundary is locked as an outward release boundary. The porous inert adsorption sheet is preferably an inert carrier (e.g., porous alumina, silica gel, or porous carbon material) loaded with a hydrophobic inert coating, and its pore size is preferably... to The preferred thickness to This allows for the physical adsorption of volatile flavor compounds carried by the inert gas during the low-temperature stage and desorption during the temperature recovery stage. The phase change material of the annular phase change temperature limiting component preferably has… to The phase transition temperature range, with the latent heat per unit mass preferably being... to The preferred quality of phase change materials to And through directional heat channels, it preferentially absorbs the peak frictional heat of the crushing chamber.

[0027] For ease of understanding and implementation, the circuit boundary lock in this specification is defined as an outward venting boundary, meaning that at the sealed gap, the sweeping airflow formed by the annular ejector nozzle and the air supply port statistically remains directed from inside the cavity to outside the cavity, thereby inhibiting outside air from flowing back into the crushing cavity through the sealed gap; correspondingly, the outward sweeping flow direction not reversing means that the mainstream direction of the sweeping airflow at the sealed gap does not undergo a reverse change from outward to inward.

[0028] In this embodiment, control and data processing are performed by a controller, which is communicatively connected to the rotor driver and the circulating power component driver. The data sources are the rotor speed and rotor drive power output from the rotor driver, and the circulating power component speed and circulating power component drive power output from the circulating power component driver. The controller reads these operating parameters at a fixed sampling period and continuously updates the runtime timer in memory. To ensure continuous and uninterrupted data processing, this embodiment sets a sampling period. for to It performs index calculation, condition judgment, and speed trajectory update once for each sampling period.

[0029] To characterize the suction intensity of the annular ejector nozzle on the inert gas at the outlet of the purification unit and the stability of the outward sweeping flow through the sealing gap, the controller is based on the rotor speed. With rotor drive power Generate moat stability index In one possible implementation, the rotor speed and rotor drive power are first normalized: Let the reference speed during the boundary locking phase be... The reference power is ,but ; The moat stability index is determined using a weighted combination relationship: Among them, weight and satisfy In this embodiment, take , The boundary locking threshold for the moat stability index is set to... The minimum suction intensity required to maintain the outward sweeping flow without reversal is defined as the minimum suction intensity; the maintenance threshold of the moat stability index is set to... This is used to continuously constrain the outward sweeping flow direction from reversing during the recharge process. In this embodiment, Pick to , Pick to .

[0030] To characterize the degree to which the annular phase change temperature limiting component is in an endothermic plateau state, the controller generates a temperature rise plateau index based on the time accumulation of rotor drive power. In this embodiment, the cumulative frictional heat index (equivalent energy accumulation) per unit time is first defined as follows: ; The heat absorption capacity calibration value of the annular phase change temperature limiting component is set to... (It can be taken as the product of the latent heat of phase change and the effective utilization coefficient), then the temperature rise plateau index is defined as follows: ; in In this embodiment, take to The temperature limiting platform range is set to... This is used to constrain the rotor speed to change along the temperature-limited crushing speed trajectory according to fine-tuning rules, so that the annular phase change temperature-limiting component absorbs peak frictional heat through the directional thermal channel and suppresses the temperature rise peak of the outer wall of the cavity; in this embodiment, Pick to , Pick to .

[0031] To characterize the load margin of the solid-phase deoxygenation bed and solid-phase dewatering bed in the purification unit, the controller collects the rotational speed of the circulating power components. With the driving power of the circulating power components And generate a purification load index In one possible implementation, a reference rotational speed for the circulating power component is set. With reference power and runtime After scaling, we obtain ; The purification load index is determined using a combination relationship: in In this embodiment, , , , Pick to The purification load threshold is set to... This is used to limit the minimum margin required to maintain the deoxygenation and dehydration depth at the outlet of the purification unit. In this embodiment... Pick to And in the fragrance extraction and pulverization stage, requirements are made .

[0032] To characterize the working state of the porous inert adsorption sheet in the same thermal coupling link as the annular phase change temperature limiting component and to achieve sequential and continuous switching of the adsorption window, desorption window, and recharge completion window, the controller is based on the temperature rise plateau index. Aroma Retention Window Index Based on Rotor Speed ​​Trajectory In this embodiment, a desorption trigger threshold is set. ,in Pick to And set the recharge trigger speed range. This is used to promote the recovery of the outer wall temperature of the chamber and the desorption of the adsorbent sheet after the rotation speed decreases. In this embodiment... Pick to , Pick to In addition, the controller measures the recharge dwell time based on whether the rotor speed is within the recharge trigger speed range. Update: When season Accumulate according to the sampling period, otherwise let Reset; and set the minimum maintenance duration for power-back. In this embodiment, to The aroma retention window index is obtained by taking discrete state values ​​using the following formula: in Corresponding adsorption window, Corresponding desorption window, The corresponding window for the complete reflow. Control logic requirement: Only when... from Switch to Only when the time is right can the refeedback triggering phase be entered; only when from Switch to Only when the recharge trigger is triggered will the inert powder output be maintained.

[0033] In this embodiment, the rotor speed trajectory includes a boundary-locking speed trajectory, a temperature-limited pulverizing speed trajectory, a recharge-triggered speed trajectory, and a powder-maintaining speed trajectory. The rotational speed trajectory of the circulating power component is linked to the rotor speed trajectory to maintain the supply and exhaust balance of the inert gas circulation loop and to provide compensation when the moat stability index is insufficient. For ease of implementation, the boundary-locking speed range is set as follows: In this embodiment Pick to , Pick to The temperature-limited pulverizing speed range is set to... In this embodiment Pick to , Pick to The powder output speed range is set to [specify]. In this embodiment Pick to , Pick to .

[0034] During implementation, before feeding begins, the purification unit's outlet supplyes deoxygenated and dehydrated inert gas to the inert gas circulation loop. The controller then activates the circulation power unit to the pre-circulation speed range (e.g., to This allows the loop to form a stable cycle, after which it enters the boundary locking phase. In step S1, boundary locking, the controller reads data at sampling intervals. and And calculate in real time Simultaneously, a boundary-locking speed trajectory is sent to the rotor driver, causing the rotor speed to change from the initial speed (e.g., ...). to )by to The ramp is raised to the boundary lock speed range and maintained; when Continuous satisfaction to The boundary locking is determined to be complete at this time. After the boundary locking is completed, the sweeping jet formed by the rotor exhaust generates an ejector negative pressure at the throat of the annular ejector nozzle. The ejector intake port draws inert gas from the outlet of the purification unit. The inert gas flows through the annular nozzle and forms an annular sheath laminar flow along the sealing gap, locking the loop boundary of the inert gas circulation loop as an outward discharge boundary. To prevent the outward sweeping flow from reversing, the controller simultaneously maintains the rotational speed of the circulating power component within the boundary-locked air supply range (e.g., to The annular sheath laminar flow continuity is maintained through the throttling branch between the gas supply section and the ejector gas supply manifold, so that the outward sweeping flow direction does not reverse.

[0035] In step S2, during the fragrance-catching and pulverizing process, the boundary locking is completed and... After the entry conditions are met, the controller begins to execute the temperature-limited pulverizing speed trajectory and continuously updates it at the sampling period throughout the entire aroma-collecting and pulverizing stage. and The fine-tuning rules for the temperature-limited pulverizer speed trajectory include segmented maintenance and segmented ramp changes of the rotor speed: when At that time, the controller will adjust the rotor speed according to... to Adjust the ramp upwards until it approaches the upper part of the temperature-limited pulverizing speed range (e.g., to To improve pulverization efficiency; when At that time, the controller performs segmented hold, that is, in to The holding section maintains a constant rotor speed, and between adjacent holding sections... to Fine-tuning the small slope to make Maintain within the temperature limiting range; when At that time, the controller will adjust the rotor speed according to... to The ramp should be adjusted to the lower part of the temperature-limited pulverizing speed range (e.g., to This reduces frictional heat input, allowing the annular phase change temperature limiting component to absorb peak frictional heat through directional thermal channels and suppress the temperature rise peak of the outer wall of the cavity.

[0036] During the aroma capture and pulverization stage, the inert gas circulation loop continuously operates under the outward venting boundary. The purification unit adaptively allocates the main purification channel and bypass channel through a differential pressure valve: when the rotational speed of the circulation power component increases, leading to an increase in the loop flow rate, the pressure difference between the main purification channel and the bypass channel increases. The differential pressure valve moves under the action of the pressure difference, increasing the opening of the bypass channel, thereby reducing the loop pressure loss under high flow conditions to maintain the powder output cycle. When the rotational speed of the circulation power component decreases or the loop flow rate decreases, the pressure difference decreases, the differential pressure valve returns to its original position, increasing the proportion of the main purification channel, thereby increasing the deoxygenation and dehydration depth under low flow conditions to meet the low-oxygen and low-dew-point conditions of the porous inert adsorption sheet adsorption and storage stage. At the same time, the porous inert adsorption sheet is in the low-temperature stage of the same thermal coupling link as the annular phase change temperature limiting component, and the volatile flavor substances carried by the inert gas are adsorbed and temporarily stored in the pores and surface of the porous inert adsorption sheet.

[0037] During step S3, when the recharge is triggered, the controller reaches the fragrance capture threshold after the fragrance-capturing and pulverizing process has continued for a certain duration. and Once the entry conditions are met, a recirculation trigger speed trajectory is sent to the rotor driver, causing the rotor speed to decrease from the temperature-limited crushing speed range to the recirculation trigger speed range and maintain it; in this embodiment Pick to As the rotational speed decreases, the heat input to the pulverizing chamber reduces, the annular phase change temperature-limiting component's heat absorption platform gradually withdraws, and the temperature of the outer wall of the chamber enters a recovery phase. The porous inert adsorption sheets desorb as the temperature of the thermal coupling link rises. The controller continuously calculates... and with Switching from the adsorption window to the desorption window is a necessary condition for the start of reinjection; when When switched to the desorption window, the desorbed volatile flavor substances are injected into the mainstream powder area of ​​the powder outlet channel through the reinjection guide pipe. Under the inert atmosphere supplied at the outlet of the purification unit, they fully contact the powder and are adsorbed onto the powder surface, thereby achieving aroma reinjection.

[0038] During the recharge process, the controller continuously constrains... To maintain laminar flow continuity in the annular sheath and ensure that the outward sweeping flow direction does not reverse; when detected At that time, the controller prioritizes increasing the rotational speed trajectory of the cyclic power component (e.g., in...). Internal adjustment to In addition, the throttling branch provides a baseline air supply pressure difference, so that the ejector air supply and the air supply from the make-up air port can jointly maintain the laminar flow continuity of the annular sheath, thereby inhibiting the backflow of outside air into the pulverizing chamber through the sealed gap.

[0039] Step S4: Inert powder dispensing continues, when... When the refilling is completed, the controller switches the rotor speed to the powder output holding speed trajectory and enters the powder output holding speed range, maintaining the powder output holding time. To achieve inert powder discharge; in this embodiment Pick to During this stage, the air supply port and the annular ejector nozzle are continuously supplied with inert gas after deoxygenation and dehydration from the air outlet of the purification unit. The outward sweeping flow direction is kept constant and does not reverse, so that the powder outlet channel and the mainstream powder area are always under an inert atmosphere. The final output powder completes the aroma re-adhesion during the inert powder outlet process and reduces the risk of oxidation and deterioration.

[0040] The outputs of this embodiment include: control outputs for the rotor driver and the circulating power component driver, i.e., continuous rotor speed trajectories and circulating power component speed trajectories; and process monitoring outputs, i.e., the moat stability index updated and recorded in each sampling period. Purification load index Temperature rise plateau index Aroma Retention Window Index The process output is the coffee powder that has completed inert powder dispensing during the inert powder holding stage. During the refilling stage, this powder receives volatile flavor compounds desorbed from the porous inert adsorption sheet and injected into the mainstream powder area, thereby inhibiting the deterioration of coffee flavor. In this embodiment, reference values ​​and thresholds are pre-stored in the controller, and the process is executed in the following order during each sampling cycle: parameter reading—exponential calculation—conditional judgment—trajectory update—execution output.

[0041] Example 2 like Figure 1 and Figure 2As shown, based on the device and process flow described in Example 1, a deterministic rule-based approach is used to generate boundary-locked speed trajectories, temperature-limited pulverizing speed trajectories, recharge-triggered speed trajectories, and powder-holding speed trajectories, without introducing new sensor data or actuator control data throughout the entire process. This approach only includes comparison and lookup table operations to form the necessary state sequence from S1 to S4. This embodiment still relies on the rotor, inert gas circulation loop, annular ejector nozzle, purification unit, annular phase change temperature-limited component, and aroma temporary storage and recharge branch of the cryogenic pulverizing device for coordinated scheduling. The difference lies in the strict limitation of the controller's data source, computation set, and control output, and the trajectory generation method is a reproducible deterministic state machine.

[0042] In this embodiment, the controller's data source is the rotor speed read from the operating parameters output by the rotor driver. With rotor drive power Read the rotational speed of the circulating power component from the operating parameters output by the circulating power component driver. With the driving power of the circulating power components The runtime is obtained from the controller's internal timing. In addition to the data sources mentioned above, the controller will not connect to any new sensors for temperature, oxygen content, dew point, pressure, flow rate, etc., nor will it connect to any new actuators or control signals used to adjust the allocation between the main purification channel and the bypass channel. The control output is limited to two types: rotor speed trajectory. Rotational speed trajectory of circulating power components The controller only sends the corresponding target speed change command to the rotor driver and the circulating power component driver. The other mechanisms (including the displacement opening change of the differential pressure valve plate) are all realized by themselves under the action of differential pressure and are not used as electrical control output objects.

[0043] To ensure continuous and uninterrupted data processing, the controller uses a fixed sampling period. (Preferred) to The following processing chain is executed in a loop: In each sampling period, read ( And update runtime The moat stability index is updated based on the above quantities. Purification load index Temperature rise plateau index Aroma Retention Window Index The system performs a comparison operation on each pre-stored set of state transition conditions to determine whether the current state meets the transition trigger. If the trigger is met, it obtains the next state and the corresponding speed corridor parameters through a lookup table and updates accordingly. and The next segment of the trajectory ensures that the control output is continuous, reproducible, and independent of random strategies.

[0044] In this embodiment, the above four indices are still determined solely by ( The generation process is as follows: Taking the moat stability index as an example, it characterizes the suction intensity of the annular ejector nozzle on the inert gas at the outlet of the purification unit and the stability of the outward sweeping flow direction of the sealing gap; taking the temperature rise plateau index as an example, it characterizes the degree to which the annular phase change temperature limiting component is in an endothermic plateau state; taking the purification load index as an example, it characterizes the load margin of the solid-phase deoxygenation bed and solid-phase dehydration bed of the purification unit; taking the aroma retention window index as an example, it characterizes the working state of the porous inert adsorption sheet in the same thermal coupling link as the annular phase change temperature limiting component and is configured to continuously switch in the order of adsorption window, desorption window, and recharge completion window. The calculation of the above indices can adopt the expression method given in Example 1, or adopt an equivalent deterministic calculation method consisting only of the above input quantities. In this embodiment, no additional quantities are introduced as calculation factors.

[0045] In one possible implementation, the aroma retention window index It can be combined with the recharge trigger speed range Construction Recharge Residence Time Quantity :when Accumulate according to the sampling period, otherwise reset; and use As a necessary condition for entering the desorption window, As a necessary condition for entering the recharge completion window, the sequential switching of the adsorption window, desorption window and recharge completion window can be achieved without introducing new sensor data collection.

[0046] To achieve deterministic cooperative scheduling that combines comparison-only and table lookup operations, the controller pre-stores two sets: a set of state transition conditions. With speed corridor set Among them, the set of state transition conditions. At least the following thresholds and window sequences should be included: the boundary locking threshold of the moat stability index. With maintenance threshold Purification load index threshold The plateau range of the temperature rise plateau index Window sequence of aroma retention window index and the fragrance capture threshold related to the duration of fragrance capture. and / or minimum duration of refill Rotational speed corridor set The allowable range and variation constraints for defining the four rotor speed trajectories and the corresponding cyclic power component speed trajectories include at least the boundary-locked speed range. Temperature-limited pulverizing speed range Recharge trigger speed range Maintain the powder output speed range and the slope change rate constraint for each segment. , With segmented duration set Rotational speed corridor set The parameters are stored in the controller's non-volatile memory or parameter area in tabular form, with each row corresponding to the corridor parameters and fine-tuning rule parameters for a certain state.

[0047] In one possible implementation, the set of state transition conditions With speed corridor set The threshold, interval, and corridor parameters can be obtained from the device's factory calibration, offline test calibration, and / or maintenance calibration, and written into the controller in the form of parameter files or parameter tables; during operation control, only comparisons and table lookups are performed to ensure the determinism and reproducibility of the scheduling rules.

[0048] In this embodiment, the controller internally sets state variables. and at discrete times with a fixed period Update. The next state is determined by a deterministic rule function. Given: in , , , The aforementioned This approach does not include continuous optimization solutions other than addition, subtraction, multiplication, and division, nor does it involve random sampling, probabilistic inference, or iterative search. Its operations consist of a finite number of comparison judgments and corresponding table lookup indices. As an implementable example, the necessary sequence of state transitions is enforced by the following comparison condition: if and only if and Continuously meet the preset confirmation time At that time, the table was consulted to obtain If and only if and and And the duration of fragrance capture and At that time, the table was consulted to obtain If and only if Furthermore, the aroma retention window index switches from the adsorption window to the desorption window and then further enters the refill completion window (i.e., When ), look up the table to get ;when And the powder dispensing timer reaches the preset powder dispensing duration. When the process ends, a table lookup is performed to determine whether the process has ended or the user has returned to standby mode. By using the above method of comparison and table lookup only, S1 to S4 are traversed in a predetermined order, avoiding jumps caused by external disturbances.

[0049] Within each state, the rotor speed trajectory and the cyclic power component speed trajectory are both generated from the corridor parameters obtained by looking up a table, and are limited and fine-tuned through comparison calculations. For the rotor speed trajectory, the controller at time... Based on the current state Target speed range obtained by looking up the table With rate of change constraint The target rotational speed for the next cycle is generated using a slope update method after the amplitude is limited. in The rules for fine-tuning segmented slopes are obtained by looking up a table and satisfy the following conditions: For temperature-limited pulverization state Specifically, the fine-tuning rule maintains the temperature rise plateau index within the plateau range through comparison calculations: when The table provides the positive slope increment when... The table is used to look up the parameters of the holding segment when... The table provides the negative ramp increment, thereby enabling segmented maintenance and segmented ramp changes of rotor speed without the need for an additional temperature sensor.

[0050] For the rotational speed trajectory of the cyclic power component, the controller determines the speed based on the state. With the moat stability index The comparison results were used to obtain the target speed range of the cyclic power components from the table. With compensation increment and generate When it is in the recharge triggered state And the comparison result is At that time, the table will be looked up Set as a positive compensation increment to improve the rotational speed trajectory of the circulating power component and, in conjunction with the throttling branch, provide a baseline supply pressure differential, thereby maintaining the laminar flow continuity of the annular sheath and ensuring that the outward sweeping flow direction remains non-reversible; when At that time, the table will be looked up Set to zero or a slowly decreasing negative increment to reduce unnecessary cycle power consumption. Since the above compensation is entirely based on... The comparison with the threshold is implemented without introducing any new actuator control variables.

[0051] Throughout the entire process of this embodiment, the adaptive allocation of the main purification channel and the bypass channel by the purification unit is still achieved by the differential pressure valve plate displacing under the pressure difference between the main purification channel and the bypass channel, resulting in a change in opening. The controller does not output any electronically controlled valve control quantity for this allocation process. The controller only... Adjust the flow rate and differential pressure level of the regulating loop, and compare the purification load index. With threshold To determine whether to allow entry into the fragrance capture and pulverization and fragrance capture stage, thereby reducing circuit pressure loss under high flow conditions and increasing deoxygenation and dehydration depth under low flow conditions, so as to meet the low oxygen and low dew point conditions of the porous inert adsorption plate adsorption temporary storage stage.

[0052] The output of this embodiment includes: the rotor speed trajectory continuously generated and distributed in each sampling period. Rotational speed trajectory of circulating power components ; and a sequence of process indicators that are updated synchronously and can be recorded. With state sequence The index sequence and state sequence are both determined by the driver's operating parameters and runtime, and the trajectory generation and state transition are determined by a pre-stored set of state transition conditions. With speed corridor set By using only comparison operations and table lookup operations, collaborative scheduling can achieve a repeatable and verifiable deterministic implementation.

[0053] Example 3 like Figures 1 to 3 As shown, based on the cryogenic pulverizing device, the coordinated scheduling object, and the moat stability index, purification load index, temperature rise plateau index, and aroma retention window index constructed solely by the rotor driver and the circulating power component driver described in Examples 1 and 2, a further embodiment is given. This embodiment is used to eliminate the influence of device differences on the set of state transition conditions before boundary locking is performed. During aroma pulverizing or recharge triggering, when the outward sweeping flow stability is insufficient, the laminar flow continuity of the annular sheath is maintained. If the maintenance conditions still cannot be met, a degraded powder discharge maintenance is performed to maintain the loop boundary as the outward venting boundary. This embodiment also performs coordinated scheduling based on the rotor of the cryogenic pulverizing device, the inert gas circulation loop, the annular ejector nozzle, the purification unit, the annular phase change temperature limiting component, and the aroma temporary storage and recharge branch. The difference lies in adding a baseline acquisition and calibration process for the no-feeding condition before S1, and introducing a deterministic switching strategy of maintenance-degradation during S2 or S3. Furthermore, the above acquisition, calibration, and switching do not introduce new sensor acquisition quantities or new actuator control quantities.

[0054] In this embodiment, the data source remains: reading the rotor speed from the rotor driver. With rotor drive power Read the rotational speed of the circulating power component from the circulating power component driver. With the driving power of the circulating power components ; and the runtime obtained from the controller's internal timing. The control output is still limited to two types: rotor speed trajectory. Rotational speed trajectory of circulating power components The adaptive allocation between the main purification channel and the bypass channel in the purification unit continues to be achieved by the displacement of the differential pressure valve plate under the action of differential pressure; the controller does not output the allocation amount of the electrically controlled valve. Inert gas is supplied from the gas outlet of the purification unit to the gas inlet and the annular ejector nozzle. A throttling branch is set between the gas supply section and the ejector gas supply manifold to provide a baseline gas supply pressure differential to maintain the laminar flow continuity of the annular sheath during gas supply fluctuations.

[0055] In this embodiment, baseline acquisition for a no-feed condition is performed before boundary locking. During the baseline acquisition phase, no coffee beans or other materials are added to the grinding chamber. The rotor and circulating power components operate at a preset baseline speed, and the controller operates at a fixed sampling period. Continuous reading , , , And complete the baseline window length. Baseline statistics within; among which Preferred to , Preferred to To ensure that the statistical results are not sensitive to transient fluctuations, the controller calculates the mean baseline for the operating parameters within the baseline window: ; ; in and The baseline acquisition results mentioned above are used to characterize the differences in bearing friction, sealing gap leakage characteristics, loop resistance, and zero-point offset of driver power readings in different devices, thereby providing consistent input for subsequent threshold and plateau range calibration.

[0056] Based on the baseline data collected above, the controller calibrates the threshold values ​​for the moat stability index, the purification load index, and the temperature rise plateau index, and writes the calibrated results into the state transition condition set. To maintain determinism and reproducibility, this embodiment limits the calibration process to table lookup and comparison: the controller pre-stores a baseline mapping table. The table is in , Using the base range and its sub-range as an index, the corresponding threshold correction amount and platform range correction amount are output; the controller obtains the correction item by looking up the table according to the base range into which the baseline mean falls, and obtains the final parameter by comparing the limit.

[0057] In one possible implementation, a baseline mapping table It can be obtained from the device's factory calibration and / or maintenance calibration, and can be updated after replacing seals, clean beds, or circulating power components; the calibration output correction items are constrained by pre-stored safety range limits, thereby improving the consistency of parameter judgment boundaries between different devices without introducing new sensor data acquisition quantities and new actuator control quantities.

[0058] In one implementation, the controller first calculates normalized baseline features for indexing: ; in and To store the reference power. The controller uses ( The corrected output is obtained by looking up a table in the range where the input falls. And update the calibrated state transition parameters as follows: in , , , , These are the initial parameters of the device after it left the factory or after the last maintenance. to To pre-store safety range limits. After calibration, the controller will... , , and Write the state transition condition set In subsequent collaborative scheduling, only the calibrated parameters are used for comparison and judgment, so that different devices can obtain consistent state transition decision boundaries under the same strategy.

[0059] After completing the baseline acquisition and calibration, the controller enters boundary locking and continues to execute the necessary state sequence from S1 to S4 as described in Examples 1 and 2. During the incense pulverization or recharge triggering, the controller continuously generates the moat stability index based on the rotor speed and rotor drive power. and the calibrated maintenance threshold A comparison is made. When the moat stability index is detected to be lower than the maintenance threshold, the controller prioritizes the maintenance strategy: increasing the rotational speed trajectory of the circulating power component and coordinating with the throttling branch to provide baseline air supply pressure difference to maintain the laminar flow continuity of the annular sheath, thereby keeping the outward sweeping flow direction from reversing.

[0060] To ensure that the maintenance strategy also satisfies deterministic implementation, this embodiment introduces a confirmation time for determining when the moat stability index falls below the maintenance threshold. Discrete counting is used for implementation. The controller calculates the comparison result in each sampling period. : And maintain a counter below the threshold ,when Increasing over time, when Reset to zero; when The system determines if the sustain trigger is successful. Once the sustain trigger is successful, the controller looks up the table to obtain the compensation increment for the cyclic power components. And increase the target speed of the circulating power components to maintain the air supply capacity within the corridor: in The baseline acquisition results are indexed to ensure that the compensation intensity matches the device loop resistance and sealing leakage characteristics. At the same time, the throttling branch provides the baseline gas supply pressure difference, so that the gas supply section and the ejector gas supply manifold can still maintain the laminar flow continuity of the annular sheath during the compensation stage.

[0061] If, after implementing the above maintenance strategy, the moat stability index remains below the maintenance threshold, the controller will execute a degradation strategy: switching the rotor speed trajectory to the powder outlet maintenance speed trajectory, and maintaining the supply of inert gas from the purification unit's outlet to keep the loop boundary as an outward venting boundary. To avoid false triggering, the controller uses a secondary confirmation time for determining if the index is still below the maintenance threshold. That is, to continue accumulating after the maintenance strategy is initiated. When the cumulative duration is below the threshold, When this occurs, the output is downgraded. The downgraded output includes: forcibly setting the state variable to the corresponding state for powder discharge maintenance, and updating the rotor target speed to the powder discharge maintenance speed range by looking up the table in the next sampling period. : Simultaneously, the target rotation speed of the circulating power component is maintained at no less than the minimum gas supply limit to ensure a continuous supply of inert gas from the outlet of the purification unit to the replenishment port and the annular ejector nozzle. Through this degradation strategy, even if insufficient ejector suction is caused by device disturbance during aroma capture and pulverization or recirculation triggering, inert powder discharge can still be completed under the continuous supply of inert gas and the maintenance of the outward venting boundary, reducing the risk of flavor deterioration caused by backflow of external air.

[0062] The output of this embodiment includes: baseline acquisition output. And the parameter output that is thus calibrated and written into the state transition condition set. Rotor speed trajectories are continuously generated and distributed during the operation phase. Rotational speed trajectory of circulating power components The outputs are recorded as follows: the sequence of events occurring during the sustaining and degrading phases of fragrance capture, pulverization, and recharge triggering. All outputs are obtained from the driver's operating parameters and the controller's timing. The calibration, sustaining, and degrading logics are all based on comparisons and table lookups, ensuring that the data processing is continuous and uninterrupted from baseline acquisition and threshold calibration to operational control.

[0063] Example 4 Based on the low-temperature pulverizing device and coordinated scheduling method described in Examples 1, 2, and 3, this example provides comparative and ablation experiment results to quantitatively illustrate the technical effects of the present invention in terms of temperature rise suppression, aroma retention, and overall sensory quality, and to verify the contribution of each technical component.

[0064] Test equipment: The low-temperature pulverizing device configured according to Example 1 includes an annular phase change temperature limiting component (1.2 kg of phase change material, phase change temperature range 20-30°C), an inert gas circulation loop, porous inert adsorption sheets, etc.

[0065] Testing instruments: K-type thermocouple temperature sensor (accuracy ±0.1°C), Agilent 7890B gas chromatograph-mass spectrometer, SCA standard sensory evaluation.

[0066] Experimental materials: Ethiopian Yirgacheffe G1 green coffee beans, per batch Each working condition was repeated 15 times, and the average value was taken. All comparison methods used the same batch of raw materials and the same target grinding fineness.

[0067] Statistical analysis notes: In one possible implementation, for continuous indicators such as temperature, aroma retention rate, and sensory scores, two independent samples can be used. Use a test of variance or one-way ANOVA to test differences between groups and set a significance level. (Preferred) When the data does not meet the assumptions of normality or homogeneity of variance, nonparametric methods such as the Mann-Whitney U test can be used. This statistical analysis is only used to illustrate the reproducibility and variability of the technical effects and does not constitute a limitation on any specific statistical method.

[0068] Note: The grinding uniformity in Table 1 is used to characterize the concentration of particle size distribution. It is preferred to use a method based on... The normalized index was obtained by conversion to Interval quantity (the larger the value, the more concentrated the particle size and the better the uniformity).

[0069] Comparative experimental results A quantitative comparison was made between the complete method of this invention and three comparative methods: Results of the comparative experiment on technical effects: Table 1

[0070] Technical Effect Analysis: Temperature Control: Compared to traditional high-speed grinding, peak temperature decreased by 48.6%, and average temperature decreased by 45.1%. Aroma Retention: Compared to low-temperature grinding, which showed higher aroma retention in the comparative method, aroma retention was improved by 13.7%. Sensory Quality: Compared to traditional high-speed grinding, sensory scores improved by 26.5%. Statistical Analysis: In... Under repeated conditions, the difference between temperature and aroma retention rate was statistically significant (preferred). The differences in sensory scores were statistically significant (preferred). ).

[0071] ablation experiment By gradually adding technical components, the independent contribution of each component is verified: Analysis of the contribution of each component in the ablation experiment: Table 2

[0072] Component contribution quantification (taking peak temperature as an example): Phase change temperature limiting component: Peak temperature is determined by... Reduce to The decline This is the main contributor to temperature rise suppression. Inert atmosphere and purification: Based on the phase transition limiting temperature, the peak temperature is further reduced. At the same time, it increases the aroma retention rate from Increase to This is used to inhibit aroma loss caused by oxidation. Aroma reinfusion: Based on an inert atmosphere, the aroma retention rate is further improved to... This is used to recover and reattach volatile flavor compounds that escape with the airflow. Coordinated scheduling: With the above hardware components in place, by timing the rotor speed trajectory and the rotational speed trajectory of the circulating power components, the peak temperature is further reduced to... And improve the aroma retention rate to .

[0073] This ablation experiment uses a step-by-step stacking of components. The improvement shown in Table 2 can be decomposed into stage increments. Furthermore, the role of coordinated scheduling is reflected in simultaneously satisfying the temperature rise platform constraint, the loop outward discharge boundary non-reversal constraint, and the aroma window switching constraint under the same complete configuration, so that temperature control and aroma retention can be balanced to achieve a better level under the same operating conditions.

[0074] Under the representative operating conditions of this embodiment, the frictional heat input during the crushing stage is approximately The upper limit of the latent heat absorption capacity of the phase change material used in the annular phase change temperature limiting component is approximately... Its capacity is sufficient to cover and reduce the peak heat input under this operating condition, thereby limiting the cavity temperature rise to near the phase transition temperature range. Approximately [amount missing] was observed in the experiment. The temperature plateau lasted for approximately 45 seconds, consistent with the phase change endothermic mechanism.

[0075] Porous inert adsorption sheets temporarily store volatile aroma compounds through physical adsorption at low temperatures, followed by desorption during the temperature recovery phase. Under a set of repeatable measurement conditions, the adsorption sheet... The adsorption capacity below is When the temperature rises to The desorption efficiency is It can increase the aroma density of the powder surface by about 156% after refilling compared to the unrefilled sample.

[0076] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be modified within the scope of the concept described herein by means of the above teachings or the technology or knowledge in related fields.

Claims

1. A low-temperature grinding method for preventing coffee flavor deterioration, characterized in that, The method involves the coordinated scheduling of the rotor, inert gas circulation loop, annular ejector nozzle, purification unit, annular phase change temperature limiting component, and aroma temporary storage and reinjection branch of the cryogenic pulverizing device. S1 boundary locking: The rotor speed and rotor drive power are collected and a moat stability index is generated accordingly. The rotor speed is controlled to increase along the boundary locking speed trajectory to the boundary locking speed range and maintained until the moat stability index reaches the boundary locking threshold. The sweeping jet formed by the rotor exhaust generates an ejector negative pressure at the throat of the annular ejector nozzle and draws inert gas from the exhaust end of the purification unit through the ejector intake port. The inert gas forms an annular sheath laminar flow from the annular nozzle outlet along the sealing gap, thereby locking the loop boundary of the inert gas circulation loop as an outward release boundary. The continuity of the annular sheath laminar flow is maintained through the throttling branch between the gas supply section and the ejector gas supply manifold so that the sweeping flow direction at the sealing gap is kept from inside the cavity to outside the cavity. The S2 aroma-catching and pulverizing unit collects the rotational speed and driving power of the circulating power component and generates a purification load index accordingly. It also generates a temperature rise plateau index based on the time accumulation of the rotor driving power. The rotor speed is controlled to change according to the fine-tuning rules along the temperature-limited pulverizing speed trajectory within the temperature-limited pulverizing speed range so that the annular phase change temperature-limiting component absorbs peak frictional heat through the directional thermal channel and keeps the temperature rise plateau index within the temperature-limited plateau range. At the same time, under the condition that the loop boundary is locked as the outward discharge boundary and the purification load index does not exceed the purification load threshold, the porous inert adsorption sheet of the aroma temporary storage and reinjection branch adsorbs and temporarily stores the volatile flavor substances carried by the inert gas in the low-temperature stage of the same thermal coupling link as the annular phase change temperature-limiting component. The purification unit adaptively allocates the main purification channel and the bypass channel under the action of the differential pressure valve. S3 recharge triggers, controlling the rotor speed to decrease from the temperature-limited pulverizing speed range to the recharge trigger speed range along the recharge trigger speed trajectory and maintain it until the aroma retention window index generated based on the temperature rise platform index and the rotor speed trajectory switches from the adsorption window to the desorption window. This causes the porous inert adsorption sheet to desorb during the temperature rise phase of the outer wall of the chamber and injects the desorbed volatile flavor substances into the mainstream powder area of ​​the powder outlet channel through the recharge guide pipe. This allows the powder to be recharged and adsorbed onto the powder surface under the inert atmosphere supplied by the gas outlet of the purification unit. During the recharge process, when the moat stability index is lower than the maintenance threshold, the speed trajectory of the circulating power component is increased and the baseline gas supply pressure difference is provided by the throttling branch to maintain the laminar flow continuity of the annular sheath. S4 inertial powder discharge maintenance controls the rotor speed to enter the powder discharge maintenance speed range along the powder discharge maintenance speed trajectory and maintain the powder discharge maintenance time, so that the air supply port and the annular ejector nozzle are continuously supplied with inert gas after deoxygenation and dehydration from the air outlet of the purification unit, so as to complete the inert powder discharge and make the aroma retention window index enter the refill completion window.

2. The low-temperature pulverization method according to claim 1, characterized in that, The control output of the coordinated scheduling only includes the rotor speed trajectory and the circulating power component speed trajectory. The moat stability index, purification load index, temperature rise plateau index, and aroma retention window index are generated only by the rotor speed, rotor drive power, circulating power component speed, circulating power component drive power, and running time. The rotor speed and rotor drive power are read from the operating parameters output by the rotor driver, and the circulating power component speed and circulating power component drive power are read from the operating parameters output by the circulating power component driver. Thus, no new sensor data acquisition or new actuator control data is introduced in the entire process.

3. The low-temperature pulverization method according to claim 1, characterized in that, The moat stability index is determined by the combination of rotor speed and rotor drive power to characterize the suction intensity of the annular ejector nozzle on the inert gas at the outlet of the purification unit and the stability of the sweeping flow direction of the sealing gap. The boundary locking threshold corresponds to limiting the minimum suction intensity at which the sweeping flow direction at the sealing gap is kept from inside the cavity to outside the cavity.

4. The low-temperature pulverization method according to claim 1, characterized in that, The temperature rise plateau index is determined by the combination of the equivalent energy accumulation of rotor drive power over time and the calibration parameters of the heat absorption capacity of the annular phase change temperature limiting component, so as to characterize the degree to which the annular phase change temperature limiting component is in the heat absorption plateau state. The fine-tuning rules of the temperature limiting crushing speed trajectory include segmented maintenance and segmented slope changes of rotor speed, so as to keep the temperature rise plateau index within the temperature limiting plateau range and suppress the temperature rise peak of the outer wall of the cavity.

5. The low-temperature pulverization method according to claim 1, characterized in that, The purification load index is determined by the combination of the rotation speed of the circulating power component, the driving power of the circulating power component, and the running time to characterize the load margin of the solid phase deoxygenation bed and the solid phase dehydration bed of the purification unit. The purification load threshold corresponds to the minimum margin required to maintain the deoxygenation and dehydration depth at the outlet of the purification unit.

6. The low-temperature pulverization method according to claim 1, characterized in that, The adaptive allocation of the main purification channel and the bypass channel by the purification unit is achieved by the displacement of the differential pressure valve plate under the pressure difference between the main purification channel and the bypass channel, resulting in a change in opening degree. The adaptive allocation process does not use an electronically controlled valve to participate in the allocation. The adaptive allocation is used to reduce the circuit pressure loss under high flow conditions to maintain the powder output cycle and to increase the proportion of the main purification channel under low flow conditions to improve the deoxygenation and dehydration depth, thereby meeting the low oxygen and low dew point conditions of the adsorption and temporary storage stage of the porous inert adsorption sheet.

7. The low-temperature pulverization method according to claim 1, characterized in that, The aroma retention window index is determined by the combination of the temperature rise plateau index and the rotor speed trajectory to characterize the working state of the porous inert adsorption sheet in the same thermal coupling link as the annular phase change temperature limiting component. It is configured to switch continuously in the order of adsorption window, desorption window, and recharge completion window, with the appearance of the desorption window as a necessary condition for entering the recharge trigger and the appearance of the recharge completion window as a necessary condition for exiting the recharge trigger.

8. The low-temperature pulverization method according to claim 1, characterized in that, The coordinated scheduling includes pre-storing the moat stability index threshold, purification load index threshold, temperature rise platform index platform interval, and aroma retention window index window sequence as a set of state transition conditions and a set of rotation speed corridors, and generating boundary locking rotation speed trajectory, temperature limiting pulverization rotation speed trajectory, recharge triggering rotation speed trajectory, and powder output maintaining rotation speed trajectory using deterministic rules that only include comparison operations and table lookup operations, thereby forming the necessary state sequence from S1 to S4.

9. The low-temperature pulverization method according to claim 1, characterized in that, The entry conditions for the fragrance-catching and pulverizing process include the moat stability index reaching the boundary locking threshold and the purification load index not exceeding the purification load threshold. The entry conditions for the recharge triggering process include the fragrance-catching duration reaching the fragrance-catching threshold and the temperature rise plateau index being in the temperature limit plateau range. During the recharge triggering period, the moat stability index is continuously constrained to be no lower than the maintenance threshold.

10. The low-temperature pulverization method according to claim 1, characterized in that, Before executing S1, the method includes reading the rotor speed, rotor drive power, and circulating power component speed and driving power from the rotor driver and circulating power component driver under no-feeding conditions, and completing baseline acquisition. Based on the baseline acquisition results, the moat stability index threshold, purification load index threshold, and temperature rise plateau index plateau range are calibrated to eliminate the influence of device differences on the set of state transition conditions. When the moat stability index generated based on the rotor speed and rotor drive power is lower than the maintenance threshold during S2 or S3, the circulating power component speed trajectory is increased and the baseline gas supply pressure difference is provided by the throttling branch to maintain the laminar flow continuity of the annular sheath. When the moat stability index is still lower than the maintenance threshold, the rotor speed trajectory is switched to the powder outlet maintenance speed trajectory and the gas supply port is supplied with inert gas from the gas outlet of the purification unit to maintain the loop boundary as an outward venting boundary.

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