A quick freezing unit, a quick freezing device, and an impact quick freezer and a control method thereof

Abstract

The application discloses a quick freezing unit, a quick freezing device, an impact quick freezing machine and a control method thereof. The quick freezing unit comprises a library body, a conveying belt and a jet air flow generating device arranged above the conveying belt. The jet air flow generating device uses a compression cylinder to compress gas to generate jet air flow groups and spray them at high speed to the conveying belt. The application uses the jet air flow generating device to generate jet air flow groups with certain temperature and high pressure, which are sprayed at high speed to the food on the conveying belt. The flow speed of the jet air flow groups can be not less than 30 m / s, so that the food can be quickly frozen or thawed. The quick freezing device can provide continuous operation. The upward and downward movement of the piston plate can provide jet air flow groups sprayed at high speed to the surface of the conveying belt, so that the food can be quickly frozen or thawed. Compared with the traditional technology, the freezing time is shorter, and the freezing quality of the food is better. The heat energy generated by the power mechanism in the library body is avoided, the energy consumption is low, and the energy efficiency of the unit is improved.

Description

Technical Field

[0001] This invention relates to the field of quick-frozen food technology, and in particular to a quick-freezing unit, quick-freezing device, and impact freezer and its control method. Background Technology

[0002] As people's living standards improve, their pursuit of food quality also increases. Some foods require quick-freezing to ensure longer storage, longer transport distances, and freshness and safety. Currently, quick-freezing technology is widely used in the food processing industry. This technology typically employs a high-speed fan to spray cold air, cooled by an evaporator, onto the food for rapid freezing. The airflow velocity is approximately 15 m / s. The high-speed airflow strikes the top and bottom surfaces of the food, breaking through the layer of hot air on the surface and carrying it away, thereby increasing the convective heat transfer efficiency between the product surface and the cold air, freezing the food at a very high speed.

[0003] A key step in the food freezing process is the formation of ice crystals, and the size, shape, and distribution of these ice crystals are major factors affecting the quality of quick-frozen food. Freezing speed is particularly important for ice crystal diameter and the degree of cell damage. The relationship between freezing speed and ice crystal diameter and the degree of cell damage is as follows: Figure 1 As shown, the faster the freezing speed, the smaller the diameter of the ice crystals formed in the food, and the less damage to the food cells. Since a higher wind speed blowing onto the food surface results in a higher heat transfer coefficient, the freezing speed is also faster. Therefore, ensuring a sufficiently high wind speed blowing onto the food surface is crucial. Traditional quick-freezing machines use fans as the air delivery device, and the wind speed of these fans is typically 10-20 m / s. Increasing the wind speed further requires using larger, more powerful fans, which not only increases size and cost but also leads to higher power consumption and heat generation, resulting in reduced energy efficiency of the unit. An existing tunnel-type quick-freezing machine… Figure 2The diagram shows the cross-sectional structure of the quick-freezing machine tunnel. The quick-freezing machine includes a conveyor belt 13 for conveying items, a quick-freezing tunnel 02 through which the conveyor belt passes, and a refrigeration device installed inside the quick-freezing tunnel. The refrigeration device includes an evaporator 03 for cooling the airflow and a fan 04 for realizing airflow circulation. A motor drives the conveyor belt to rotate cyclically. Items are placed at the feed end of the conveyor belt, and after being frozen by the airflow, they are sent out from the discharge port of the conveyor belt. A guide shroud 06 covers the conveyor belt to guide the freezing airflow to the items on the conveyor belt. The fan is installed on the upper part of the guide shroud, connecting the inner and outer spaces of the guide shroud. The air inlet 401 of the fan is connected to the lower space of the conveyor belt through an external air duct 07 located outside the guide shroud; that is, the external air duct is between the outside of the guide shroud and the tunnel. The evaporator is installed on the external air duct. The fan causes the airflow entering through its air inlet to be cooled by the evaporator and then transported back to the conveyor belt inside the guide shroud. The evaporator is connected to the external refrigeration unit through the liquid supply port 301 and the steam return port 302. The evaporator is located at the top of the external air duct, and a spray pipe 08 for defrosting the evaporator is provided above the evaporator pipe. The external air duct consists of two ducts on both sides of the conveyor belt, and each external air duct is equipped with evaporator pipes, making the structure symmetrical. The fan is located between the two evaporators. The fan is a centrifugal fan with its air inlet facing upward and its centrifugal outlet 402 facing downward and located inside the guide shroud. The airflow passing through the conveyor belt from top to bottom enters the external air duct through the guide port 010 below the guide shroud to form a heat exchange cycle.

[0004] When the tunnel-type quick-freezing machine is working, the fan rotates and draws in the freezing airflow from the outer air duct through its air inlet. The centrifugal outlet of the fan then blows the freezing airflow rapidly onto the items on the conveyor belt, causing the items to freeze quickly and maintain freshness. The airflow blowing over the items travels from top to bottom through the conveyor belt and enters the outer air duct through the guide port below the guide shroud. It is then drawn back into the evaporator for cooling and heat exchange. The freezing airflow passing through the evaporator is then drawn back into the air inlet, creating a continuous quick-freezing process for the items.

[0005] As shown above, the freezing airflow blowing onto items for quick freezing is driven by a fan. However, the rated power of a fan is fixed, and commonly used fans produce wind speeds not exceeding 20 m / s. To achieve wind speeds higher than 20 m / s, a high-power fan must be selected. Large fans are bulky, expensive, consume a lot of electricity, and generate a lot of heat. Moreover, large fans are located inside air ducts, with heat dissipating within the tunnel. Overall, this leads to a reduction in the unit's energy efficiency.

[0006] Therefore, overcoming the shortcomings of existing tunnel-type quick-freezing machines, such as low air velocity in frozen foods, inability to meet the requirements of quick-freezing quality, and reduced energy efficiency of the unit, is a problem that needs to be solved in this field. Summary of the Invention

[0007] This invention addresses the problems of low airflow velocity in existing tunnel-type quick-freezing machines, which fails to meet the requirements for quick-freezing quality, and reduced energy efficiency of the units. It provides a quick-freezing unit, quick-freezing device, and impact quick-freezing machine with high airflow velocity and high energy efficiency, along with their control method.

[0008] The present invention provides a quick-freezing unit, including a storage chamber and a conveyor belt disposed within the storage chamber, characterized in that it further includes a jet airflow generator disposed above the conveyor belt, wherein the jet airflow generator uses a compression cylinder to compress gas to generate a jet airflow group with high pressure and sprays it at high speed toward the conveyor belt.

[0009] Preferably, the jet airflow generating device includes a piston compression mechanism, a first heat exchanger, and an orifice plate arranged in sequence; the piston compression mechanism draws in gas from the tank, compresses it, passes it through the first heat exchanger, and then through the orifice plate to generate a jet airflow group, which is then sprayed at high speed toward the conveyor belt.

[0010] Preferably, the diameter of the through holes on the perforated plate is 3-5 mm; the opening ratio of the perforated plate is 2.5%-3.3%; and the displacement speed of the piston plate is not less than 1 m / s.

[0011] Preferably, the piston compression mechanism includes a cylinder and a piston plate disposed in the inner cavity of the cylinder that reciprocates, thereby drawing in and compressing gas through the reciprocating movement of the piston plate.

[0012] Preferably, the volume between the piston plate and the first heat exchanger is used to draw gas from the reservoir through a first one-way valve; while a second one-way valve for air intake is provided on one side of the cylinder wall above the piston plate, and a third one-way valve for air exhaust is provided on the other side.

[0013] Preferably, a second proximity switch is provided in the cylinder body near the first one-way valve, and a first proximity switch is provided near the second one-way valve.

[0014] Preferably, the power mechanism that drives the piston plate to move up and down is located outside the tank body.

[0015] This invention provides a quick-freezing device, including the aforementioned quick-freezing unit, an adjusting plate above an orifice plate, and an adjusting mechanism that drives the adjusting plate to close or open an airflow passage through a first heat exchanger. The volume above the piston plate draws in and compresses gas; the compressed gas is discharged through a second heat exchanger in an independent chamber and then flows directly through the orifice plate to generate a jet airflow group, which is then sprayed at high speed onto the conveyor belt; the adjusting mechanism causes the adjusting plate to close the airflow passage through the first heat exchanger.

[0016] Preferably, the volume on the upper side of the piston plate draws in gas through the second one-way valve and then discharges compressed gas through the third one-way valve, with the compressed gas flowing through the second heat exchanger.

[0017] The present invention also provides an impact freezer, comprising two sets of freezers symmetrically installed above and below the conveyor belt.

[0018] Preferably, the power mechanism drives the piston plates in the two quick-freezing devices to move up and down synchronously.

[0019] This invention provides a control method for an impact freezer, comprising the following steps:

[0020] Step 1: Based on whether the first proximity switch A1 and the second proximity switch A2 detect the piston plate in the upper quick-freezing device, drive the piston plates in the upper and lower quick-freezing devices to move up and down in linkage.

[0021] Step 2: When the first proximity switch A1 detects the piston plate in the upper quick-freezing device, it drives the piston plates of the upper and lower quick-freezing devices to move downwards simultaneously.

[0022] The compressed air from the piston plate of the upper quick-freezing device passes through the first heat exchanger and then through the perforated plate before being sprayed onto the conveyor belt; the compressed air from the lower piston plate of the lower quick-freezing device passes through the lower second heat exchanger and then through the lower perforated plate before being sprayed onto the conveyor belt; at this moment, the channel flowing down to the lower first heat exchanger is closed.

[0023] Step 3: When the second proximity switch A2 detects the piston plate in the upper quick-freezing device, it drives the piston plates of the upper and lower quick-freezing devices to move upward simultaneously.

[0024] The compressed air from the piston plate of the upper quick-freezing device passes through the second heat exchanger and then through the perforated plate before being sprayed onto the conveyor belt, at which point the channel flowing to the first heat exchanger is blocked; the compressed air from the lower piston plate of the lower quick-freezing device passes through the lower first heat exchanger and then through the lower perforated plate before being sprayed onto the conveyor belt.

[0025] This invention provides a novel impact-type quick-freezing device that utilizes the vertical displacement of a piston plate within a cylinder to compress air. The compressed air, after heat exchange in a heat exchanger, is then passed through a perforated plate to generate a jet stream with a certain temperature and high pressure, which is then sprayed at high speed onto the food on a conveyor belt. The flow velocity of this jet stream is not less than 30 m / s, enabling rapid freezing or thawing of the food. The quick-freezing unit provided by this invention has a simple structure and is easy to operate. The quick-freezing device can provide continuous operation, meaning that the vertical movement of the piston plate can consistently provide a high-speed jet stream sprayed onto one surface of the conveyor belt. The impact-type quick-freezing machine provided by this invention can drive the piston plates in two symmetrically arranged quick-freezing devices to move synchronously up and down. Each compression movement of the piston plate provides a continuous high-speed jet stream sprayed onto both sides of the conveyor belt, resulting in high working efficiency. Compared to traditional quick-freezing machines, this invention offers higher airflow, shorter freezing time, smaller ice crystals, and superior food quality. Furthermore, the power mechanism can be located outside the freezer, avoiding the generation of heat energy inside the freezer compared to traditional quick-freezing machines, resulting in lower energy consumption and improved unit energy efficiency. If the heat exchanger in the quick-freezing machine is selected as an evaporator, it can be used for rapid and high-quality freezing of food; if the heat exchanger is a condenser, it can also be used for rapid and high-quality thawing of food. This invention is flexible in use and has a wide range of applications. Attached Figure Description

[0026] Figure 1 It is a graph showing the relationship between the freezing speed of food and the diameter of ice crystals and the degree of cell damage;

[0027] Figure 2 This is a cross-sectional structural diagram of an existing tunnel-type quick-freezing machine;

[0028] Figure 3 This is a schematic diagram of the structure of an embodiment of the quick-freezing unit of the present invention;

[0029] Figure 4 yes Figure 3 A schematic diagram illustrating the working principle of the piston plate during downward compression in the embodiment;

[0030] Figure 5 yes Figure 3 A schematic diagram illustrating the working principle of the piston plate during upward compression in the embodiment;

[0031] Figure 6 This is a schematic diagram of the structure of an embodiment of the quick-freezing device of the present invention;

[0032] Figure 7 yes Figure 6 A schematic diagram illustrating the working principle of the piston plate during downward compression in the embodiment;

[0033] Figure 8 yes Figure 6 A schematic diagram illustrating the working principle of the piston plate during upward compression in the embodiment;

[0034] Figure 9 This is a schematic diagram of the structure of an embodiment of the impact freezer of the present invention;

[0035] Figure 10 yes Figure 9 Schematic diagram illustrating the working principle of the piston plate of the quick-freezing machine during downward compression;

[0036] Figure 11 yes Figure 9 Schematic diagram illustrating the working principle of the piston plate of the quick-freezing machine during upward compression;

[0037] Figure 12 This is a schematic diagram of the working process control of the impact freezer of the present invention.

[0038] Existing technology Figure 2 In the middle: 13-conveyor belt, 02-quick-freezing tunnel, 03-evaporator, 301-liquid supply port, 302-steam return port, 04-fan, 401-air inlet, 402-centrifugal outlet, 06-guide hood, 07-external air duct, 08-spray pipe, guide port 010;

[0039] In the figures of this invention: 1-tank body; 2-piston plate; 3-third check valve; 4-second check valve; 5-first check valve; 6-first heat exchanger; 7-second heat exchanger; 8-adjusting plate; 9-fixed plate; 10-adjusting mechanism; 11-orifice plate; 12-food; 13-conveyor belt;

[0040] 14-Lower adjusting plate; 15-Lower fixed plate; 16-Lower adjusting mechanism; 17-Lower first heat exchanger; 18-Lower second heat exchanger; 19-Lower piston plate; 20-Fourth check valve; 21-Fifth check valve; 22-Sixth check valve; 23-Lower orifice plate; 24-Cylinder body; 25-Lower cylinder body. Detailed Implementation

[0041] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0042] Current traditional quick-freezing machines use fans as air delivery devices, and the air speed generated by these fans is typically 10-20 m / s. Increasing the air speed further requires larger, more powerful fans, which not only increases size and cost but also leads to higher power consumption and heat generation, resulting in reduced energy efficiency. For example, an existing tunnel-type quick-freezing machine… Figure 2The diagram shows the cross-sectional structure of the quick-freezing machine tunnel. The quick-freezing machine includes a quick-freezing tunnel 02, a conveyor belt 13, and a refrigeration unit. The refrigeration unit includes an evaporator 03 and a fan 04. A guide shroud 06 covers the conveyor belt to direct the freezing airflow onto the items on the conveyor belt. The fan, connecting the inner and outer spaces of the guide shroud, is located on the upper part of the guide shroud. The fan's air inlet 401 is connected to the lower space of the conveyor belt through an external air duct 07 located outside the guide shroud; that is, the external air duct is located between the outside of the guide shroud and the inner wall of the tunnel. An evaporator is located on the upper part of the external air duct. The airflow cooled by the evaporator is drawn into the guide shroud by the fan and blown onto the conveyor belt. The airflow passes through the conveyor belt from top to bottom and then enters the external air duct from the guide port 010 below the guide shroud to form a heat exchange cycle.

[0043] When a tunnel-type quick-freezing machine is operating, a fan rapidly blows a freezing airflow onto the items on the conveyor belt, causing them to freeze quickly and maintain freshness. As we can see, the freezing airflow blowing onto the items for quick freezing is driven by a fan. However, the rated power of a fan is fixed, and commonly used fans produce wind speeds not exceeding 20 m / s. To achieve wind speeds higher than 20 m / s, a high-power fan must be selected. Large fans are bulky, expensive, consume a lot of electricity, and generate a lot of heat. Moreover, large fans are located inside the tunnel, and the heat from the fans dissipates within the tunnel. In short, this leads to a reduction in the overall energy efficiency of the unit.

[0044] like Figure 3 As shown, an embodiment of a quick-freezing unit provided by the present invention includes a storage chamber 1 and a conveyor belt 13 disposed within the storage chamber. The storage chamber can be understood as a closed tunnel, and food 12 can be placed on the conveyor belt. A jet airflow generator is also provided above the conveyor belt. This jet airflow generator uses a compression cylinder mechanism to compress gas to generate a jet airflow group with a certain temperature and high pressure, which is then sprayed at high speed onto the conveyor belt, i.e., onto the food on the conveyor belt, for rapid freezing or thawing.

[0045] In this embodiment, the jet gas generating device includes a piston compression mechanism, a first heat exchanger 6, and an orifice plate 11 arranged sequentially. The piston compression mechanism draws in gas from the storage body, compresses it, exchanges heat through the first heat exchanger below, and then generates a jet gas stream with a certain temperature and high pressure through the orifice plate, which is then sprayed at high speed onto the food on the conveyor belt for rapid freezing or thawing.

[0046] Please combine Figure 4 , Figure 5The piston compression mechanism includes a cylinder 24 and a piston plate 2 that reciprocates within the cylinder cavity. The reciprocating movement of the piston plate draws in and compresses gas. A first one-way valve 5 for air intake is located on the cylinder wall between the lower side of the piston plate and the first heat exchanger. A second one-way valve 4 for air intake is located on the left side of the cylinder wall above the piston plate, while a third one-way valve 3 for air exhaust is located on the right side. When the piston plate moves upward, the cylinder volume below the piston plate can draw in gas from the storage chamber through the first one-way valve to store the gas. Then, when the piston plate moves downward, it compresses the air downward, forcing it through the first heat exchanger and orifice plate below to generate a jet of air with a certain temperature, which is then sprayed at high speed onto the food on the conveyor belt. Simultaneously, the second one-way valve draws in gas from the storage chamber to store it. When the piston plate moves upward, the second one-way valve closes, and the third one-way valve 3 discharges pressurized gas into the storage chamber. At the same time, the first one-way valve draws in gas from the storage chamber to store it, thus performing a gas intake and compression cycle. The perforated plate has a diameter of 3-5 mm and an opening ratio of 2.5%-3.3%. The piston plate has a displacement velocity of not less than 1 m / s. The gas is first compressed by the piston plate of the compression cylinder and then further pressurized by the perforated plate, resulting in a jet stream velocity of ≥30 m / s. This is more than 50% higher than the wind speed of ≤20 m / s generated by existing fans, significantly improving the quality of frozen foods. Therefore, the jet stream of this invention is a high-speed airflow group composed of many parallel airflow columns, which is first compressed and then ejected through the perforated plate.

[0047] To achieve automatic control of the quick-freezing unit, a second proximity switch A2 is located near the first one-way valve within the cylinder, and a first proximity switch A1 is located near the second one-way valve. The power mechanism driving the piston plate to move up and down can be a high-power pneumatic or hydraulic transmission mechanism, and this power mechanism is located outside the freezer body to dissipate the heat it generates. The power mechanism, as well as the first and second proximity switches, are electrically connected to the unit's controller for automatic control. When the first proximity switch within the quick-freezing unit cylinder detects the piston plate of the quick-freezing device, the controller controls the power mechanism to drive the piston plate downwards. When the second proximity switch within the quick-freezing unit cylinder detects the piston plate, the controller controls the power mechanism to drive the piston plate upwards. The quick-freezing unit provided by this invention has a simple structure, low cost, convenient operation, and high energy efficiency.

[0048] like Figure 6As shown, an embodiment of a quick-freezing device provided by the present invention includes the aforementioned quick-freezing unit, namely, a storage chamber and a conveyor belt disposed within the storage chamber. Food can be placed on the conveyor belt. A jet airflow generator is provided above the conveyor belt. This jet airflow generator uses a compressor cylinder to compress gas to generate a jet airflow group with a certain temperature and high pressure, which is then sprayed at high speed onto the conveyor belt, i.e., onto the food on the conveyor belt, for rapid freezing or thawing.

[0049] The jet gas generating device includes a piston compression mechanism, a first heat exchanger, and an orifice plate arranged sequentially. Preferably, the piston compression mechanism includes a cylinder and a piston plate that reciprocates within the cylinder cavity, drawing in and compressing gas through the reciprocating movement of the piston plate. A first one-way valve for air intake is provided on the cylinder wall between the lower side of the piston plate and the first evaporator, and a second one-way valve for air intake is provided on the left side of the cylinder wall above the piston plate, while a third one-way valve for air exhaust is provided on the right side.

[0050] like Figure 7 As shown, when the piston plate moves upward, the cylinder volume below the piston plate can draw in gas from the storage chamber through the first one-way valve to store the gas. When the downward compression of air through the piston plate forces the air to exchange heat through the first heat exchanger below, and then through the perforated plate, it generates a jet stream with a certain temperature and high pressure, which is then sprayed at high speed onto the food on the conveyor belt. While the piston plate moves downward to compress, the second one-way valve draws in gas from the storage chamber to store the gas. The first and third one-way valves are closed. When the piston plate moves upward to compress, the pressurized gas is discharged through the third one-way valve, and the second one-way valve closes. Simultaneously, gas is drawn in from the storage chamber through the first one-way valve, storing the gas, thus performing a gas intake and compression cycle. The orifice diameter on the perforated plate is 3-5 mm; the orifice ratio is 2.5%-3.3%; and the displacement velocity of the piston plate is not less than 1 m / s. This allows the velocity of the jet stream generated through the perforated plate to be increased to ≥30 m / s. Compared to existing fans that produce wind speeds of ≤20m / s, this represents an increase of more than 50%.

[0051] In this embodiment, an adjusting plate 8 and an adjusting mechanism 10 for driving the adjusting plate to close or open the channel are provided above the perforated plate of the quick-freezing unit. The adjusting mechanism is electrically connected to the unit's controller. A fixing plate 9 for fixing the adjusting plate is also provided below the adjusting plate. During operation, as the piston plate moves downward, the cylinder volume above the piston plate first draws in gas from the storage chamber through the second one-way valve to store the gas.

[0052] like Figure 8As shown, when the piston plate moves upward to compress, the compressed gas can be discharged through the third one-way valve. The discharged compressed gas enters an independent cavity and is heated by the second heat exchanger 7 located in this independent cavity. The pressurized gas with a certain temperature then enters the cavity between the fixed plate and the perforated plate of the quick-freezing unit. It generates a downward jet of gas through the perforated plate and is sprayed at high speed onto the food on the conveyor belt. At this moment, the controller controls the regulating plate through the adjusting mechanism to close the channel for the gas to enter the inner cavity of the cylinder through the first heat exchanger. That is, the pressurized gas after being heated by the second heat exchanger cannot enter the inner cavity of the cylinder upward and can only be sprayed downward. Similarly, when the piston plate compresses the air downward, forcing the air to generate a jet of gas with a certain temperature and pressure through the first heat exchanger and the perforated plate below and spray it at high speed onto the food on the conveyor belt, the controller controls the regulating plate through the adjusting mechanism to open the channel, allowing the pressurized gas to pass through the through holes of the perforated plate. That is, the pressurized gas after being heated by the first heat exchanger can pass downward through the perforated plate and be sprayed onto the food on the conveyor belt. Depending on the requirements, the regulating mechanism can be selected from solenoid valves, pneumatic transmission mechanisms, or hydraulic transmission mechanisms.

[0053] This quick-freezing device can operate continuously, meaning that the upward or downward movement of the piston plate can provide a high-speed jet of airflow directed onto a surface of the conveyor belt. This improves the efficiency of defrosting food and facilitates automated control.

[0054] like Figure 9 As shown, the present invention provides an impact freezer comprising two sets of freezers symmetrically installed above and below a conveyor belt. Specifically, the upper freezer faces downwards toward the front of the conveyor belt, and the lower freezer faces upwards toward the back of the conveyor belt. The lower freezer includes: a lower cylinder 25, a lower piston plate 19, a lower perforated plate 23 facing the conveyor belt, a lower adjusting plate 14 located below the lower perforated plate, a lower adjusting mechanism 16, and a lower fixed plate 15. A lower first heat exchanger 17 is provided between the lower fixed plate and the lower piston plate. A fourth one-way valve 20 for air intake is provided on the wall of the lower cylinder above the upper surface of the lower piston plate, and a fifth one-way valve 21 for air intake and a sixth one-way valve 22 for air exhaust are respectively provided on the side walls of the lower cylinder below the lower surface of the lower piston plate. The sixth one-way valve connects to an independent cavity, in which a lower second heat exchanger 18 is provided. After passing through the second heat exchanger, the gas flows into the space between the lower orifice plate and the lower regulating plate, and then rises through the lower orifice plate to generate a jet stream with a certain temperature and high pressure, which is then sprayed at high speed toward the back of the conveyor belt.

[0055] The two quick-freezing devices of this invention are symmetrically arranged vertically, and can simultaneously spray airflow onto the upper and lower surfaces of the conveyor belt. The conveyor belt can be designed with a mesh structure to allow airflow to pass through. A power mechanism located outside the freezer can simultaneously drive the piston plates in the two quick-freezing devices to move up and down synchronously.

[0056] This invention provides a control method for an impact freezer, comprising the following steps: Figure 12 As shown:

[0057] Step 1: Based on whether the first proximity switch A1 and the second proximity switch A2 detect the piston plate in the upper quick-freezing device, drive the piston plates in the upper and lower quick-freezing devices to move up and down in linkage.

[0058] Step 2: When the first proximity switch A1 detects the piston plate in the upper quick-freezing device, it drives the piston plates of the upper and lower quick-freezing devices to move downwards simultaneously.

[0059] The compressed air from the piston plate of the upper quick-freezing device passes through the first heat exchanger and then through the perforated plate before being sprayed onto the conveyor belt; the compressed air from the lower piston plate of the lower quick-freezing device passes through the lower second heat exchanger and then through the lower perforated plate before being sprayed onto the conveyor belt, at which point the channel flowing down to the lower first heat exchanger is blocked.

[0060] Step 3: When the second proximity switch A2 detects the piston plate in the upper quick-freezing device, it drives the piston plates of the upper and lower quick-freezing devices to move upward simultaneously.

[0061] The compressed air from the piston plate of the upper quick-freezing device passes through the second heat exchanger and then through the perforated plate before being sprayed onto the conveyor belt; at this moment, the channel flowing to the first heat exchanger is closed; the compressed air from the lower piston plate of the lower quick-freezing device passes through the lower first heat exchanger and then through the lower perforated plate before being sprayed onto the conveyor belt.

[0062] The embodiment of the impact freezer of the present invention operates as follows:

[0063] like Figure 10 As shown, when the first proximity switch A1 located in the cylinder of the upper quick-freezing device detects the piston plate of the upper quick-freezing device, the controller of the quick-freezing machine controls the power mechanism to drive the two piston plates in the upper and lower quick-freezing devices to move down in linkage, that is, to move down simultaneously.

[0064] For the upper quick-freezing unit, the downward movement of the piston plate opens the second one-way valve, drawing in and storing gas from the storage chamber, while the first and third one-way valves remain closed. The piston plate compresses the air downwards, forcing it through the first heat exchanger below for heat exchange, and then through the orifice plate to generate a jet of gas with a specific temperature and pressure, which is then sprayed at high speed onto the food on the conveyor belt. After exchanging heat with the food, the gas flows back into the storage chamber. At this time, the controller opens the regulating plate via the adjusting mechanism. This means that the pressurized gas, after heat exchange in the first heat exchanger, can only be ejected downwards through the orifice plate and cannot flow in other directions.

[0065] Simultaneously, in the lower quick-freezing unit, the lower piston plate moves downward, causing the fourth one-way valve to open and draw in gas from the storage chamber, storing the gas, while the fifth one-way valve closes. The lower piston plate compresses the air downward, forcing the air to open the sixth one-way valve below to expel the gas. The expelled pressurized gas passes through the lower second heat exchanger and exchanges heat, then through the through-holes of the lower perforated plate to generate a jet of gas with a certain temperature and pressure, which is then sprayed upward at high speed onto the lower surface of the conveyor belt and through the conveyor belt onto the food. After exchanging heat with the food, it flows back into the storage chamber. At this moment, the controller has already controlled the lower regulating mechanism to drive the lower regulating plate to close the channel for gas to flow down to the lower first heat exchanger, meaning that the pressurized gas cannot enter the lower first heat exchanger downwards, but can only be sprayed upwards through the lower perforated plate.

[0066] like Figure 11 As shown, when the second proximity switch A2 located in the cylinder of the upper quick-freezing device detects the piston plate of the upper quick-freezing device, the controller controls the power mechanism to drive the two piston plates in the upper and lower quick-freezing devices to move upward in linkage, that is, to move upward simultaneously.

[0067] For the upper quick-freezing unit, the upward movement of the piston plate opens the first one-way valve, drawing in and storing gas from the storage chamber. The second one-way valve closes, and the third one-way valve discharges compressed gas. This discharged compressed gas, after being heated by the second heat exchanger, reaches a certain temperature and pressure, which is then sprayed at high speed through the orifice plate onto the food on the conveyor belt. After exchanging heat with the food, it flows back into the storage chamber. At this moment, the controller, through the adjusting mechanism, controls the adjusting plate to close the channel through which gas flows upward through the first heat exchanger into the inner cavity of the cylinder. That is, the pressurized gas, after being heated by the second heat exchanger, cannot enter the inner cavity of the cylinder upwards; it can only be sprayed downwards through the orifice plate.

[0068] Simultaneously, in the lower quick-freezing unit, the upward movement of the lower piston plate opens the fifth one-way valve, drawing in and storing gas from the storage chamber. At this time, the fourth and sixth one-way valves close. The upward compression of the air by the lower piston plate forces the air through the upper lower first heat exchanger for heat exchange, and then through the lower orifice plate to generate a jet of gas with a certain temperature and pressure, which is then sprayed at high speed onto the conveyor belt and the food. After exchanging heat with the food, it flows back into the storage chamber. At this time, the controller controls the lower regulating plate to open via the lower regulating mechanism. That is, the pressurized gas after heat exchange in the lower first heat exchanger can only be sprayed upward through the lower orifice plate and cannot flow in other directions.

[0069] When the impact freezer of this invention is used for quick-freezing food, the heat exchangers in the freezer are all evaporators of the refrigeration system. After air exchanges heat with the evaporator, it becomes lower-temperature refrigerated air for preserving the frozen food. Conversely, when the impact freezer is used for rapidly thawing food, the heat exchangers in the freezer are all condensers of the refrigeration system. After air exchanges heat with the condenser, it becomes higher-temperature hot air for rapidly thawing the food. This invention has a wide range of applications and high energy efficiency.

[0070] The impact freezer provided by this invention utilizes the vertical displacement of a piston plate in the cylinder to compress air. The compressed gas, after heat exchange in a heat exchanger, is then propelled at high speed through a perforated plate to generate a jet stream that is sprayed onto the food on the conveyor belt. The flow velocity of the jet stream is ≥30 m / s, enabling rapid freezing or thawing of the food. Because it can drive the piston plates in two symmetrically arranged freezer units to move synchronously up and down, each compression of the piston plate provides a continuous high-speed jet stream that is sprayed onto both sides of the conveyor belt, resulting in high efficiency. Compared to traditional freezers, it offers higher airflow, shorter freezing time, smaller ice crystals, and superior food quality. Furthermore, the power mechanism can be located outside the freezer, avoiding heat generation inside the freezer compared to traditional freezers, resulting in lower energy consumption and improved unit energy efficiency.

[0071] The above description is merely an embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A quick-freezing device, comprising a storage chamber, a conveyor belt disposed within the storage chamber, and a jet airflow generator disposed above the conveyor belt, wherein the jet airflow generator uses a compression cylinder to compress gas and generate a jet airflow group that is sprayed at high speed toward the conveyor belt; the jet airflow generator includes a piston compression mechanism, a first heat exchanger, and an orifice plate arranged sequentially; the piston compression mechanism draws in gas from the storage chamber, compresses it, passes it through the first heat exchanger, and then through the through holes of the orifice plate to generate the jet airflow group, which is then sprayed at high speed toward the conveyor belt; the piston compression mechanism includes a cylinder and a piston plate disposed within the cavity of the cylinder that reciprocates, thereby drawing in and compressing gas; characterized in that... An adjusting plate and an adjusting mechanism for driving the adjusting plate to close or open the airflow passage through the first heat exchanger are provided above the orifice plate; the volume above the piston plate draws in and compresses gas, and the compressed gas is discharged through the second heat exchanger in the independent cavity and then flows directly through the orifice plate to generate the jet airflow group and is sprayed at high speed onto the conveyor belt; the adjusting mechanism causes the adjusting plate to close the airflow passage through the first heat exchanger.

2. The quick-freezing apparatus as described in claim 1, characterized in that, The volume between the piston plate and the first heat exchanger draws in gas from the tank through the first one-way valve; while the cylinder above the piston plate is provided with a second one-way valve for air intake on one side and a third one-way valve for air exhaust on the other side.

3. The quick-freezing apparatus as described in claim 2, characterized in that, Gas is drawn in through the second one-way valve and then discharged through the third one-way valve. The compressed gas then flows through the second heat exchanger.

4. The quick-freezing apparatus as described in claim 2, characterized in that, A second proximity switch is provided in the cylinder body near the first one-way valve, and a first proximity switch is provided near the second one-way valve.

5. The quick-freezing apparatus as described in claim 1, characterized in that, The diameter of the through hole is 3-5 mm; the opening ratio of the perforated plate is 2.5%-3.3%; and the displacement speed of the piston plate is not less than 1 m / s.

6. The quick-freezing apparatus as described in claim 1, characterized in that, The power mechanism that drives the piston plate to move up and down is located outside the tank body.

7. An impact freezer, characterized in that, It includes two quick-freezing devices as described in any one of claims 1 or 6, the two quick-freezing devices being installed symmetrically above and below the conveyor belt.

8. The impact freezer as described in claim 7, characterized in that, The power mechanism drives the piston plates in the two quick-freezing devices to move up and down synchronously.

9. A control method for an impact freezer as described in claim 7 or 8, characterized in that, Includes the following steps: Step 1: Based on whether the first proximity switch and the second proximity switch detect the piston plate in the upper quick-freezing device, drive the piston plates in the upper and lower quick-freezing devices to move up and down in unison. Step 2: When the first proximity switch detects the piston plate in the upper quick-freezing device, it drives the piston plates of the upper and lower quick-freezing devices to move downwards simultaneously. The compressed air from the piston plate of the upper quick-freezing device passes through the first heat exchanger and then through the perforated plate before being sprayed onto the conveyor belt; the compressed air from the lower piston plate of the lower quick-freezing device passes through the lower second heat exchanger and then through the lower perforated plate before being sprayed onto the conveyor belt, at which point the channel flowing down to the lower first heat exchanger is blocked. Step 3: When the second proximity switch detects the piston plate in the upper quick-freezing device, it drives the piston plates of the upper and lower quick-freezing devices to move upward simultaneously. The compressed air from the piston plate of the upper quick-freezing device passes through the second heat exchanger and then through the perforated plate before being sprayed onto the conveyor belt, at which point the channel flowing to the first heat exchanger is blocked; the compressed air from the lower piston plate of the lower quick-freezing device passes through the lower first heat exchanger and then through the lower perforated plate before being sprayed onto the conveyor belt.

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