Fruit and vegetable dryer with air heat source heat pump

Abstract

The utility model discloses an air heat source heat pump fruit and vegetable dryer, which relates to the technical field of drying equipment and comprises a shell, a hot air pipeline system and a plurality of layers of vertically arranged drawer type bearing plates, grid holes are arranged at the bottom of each layer of bearing plate, and a pulse turnover device is correspondingly arranged below each layer of bearing plate. The pulse turning-over device adopts a main air pipe-branch air pipe air path layout, compressed air is periodically released through a pulse valve, is guided through a one-way valve and then enters a Venturi pipe to be accelerated, high-speed jet flow is formed to penetrate through grid holes to drive materials to turn over, and the technical problems that according to traditional drying equipment, materials are locally overheated, and drying is uneven are effectively solved.

Description

Technical Field

[0001] This utility model belongs to the technical field of drying equipment, specifically relating to an air heat source heat pump fruit and vegetable dryer. Background Technology

[0002] In the fruit and vegetable processing industry, drying is a crucial process for extending product shelf life and preserving nutritional components. Traditional drying technologies mainly rely on natural air drying or electric heating equipment, which suffer from low thermal efficiency, poor temperature control precision, and easy loss of nutrients. With the development of heat pump technology, air source heat pump dryers have gradually become the industry mainstream due to their energy-saving and environmentally friendly characteristics.

[0003] However, traditional tray-type drying equipment uses a static stacking method, which can easily lead to localized overheating or insufficient drying of fruits and vegetables due to differences in the rate of surface moisture evaporation. In particular, for leafy materials (such as mint leaves and tea leaves) or sliced ​​fruits and vegetables (such as apple slices and dried sweet potatoes), their flat structure tends to adhere to the bearing surface, which hinders the evaporation of moisture at the bottom and requires manual intervention to turn them over, which increases labor intensity and damages the integrity of the materials.

[0004] Therefore, a heat pump fruit and vegetable dryer that can turn the dried materials over is needed. Utility Model Content

[0005] In order to overcome the problems existing in the background art, the present invention provides a hot air circulation device for a fruit and vegetable dryer.

[0006] To achieve the above objectives, this utility model is implemented through the following technical solution: an air heat source heat pump fruit and vegetable dryer, comprising: a shell, a hot air duct system connected to the shell, multiple drawer-type support trays vertically distributed within the shell, and a pulse turning device disposed below each layer of the support trays; the bottom of the support trays is provided with grid holes;

[0007] The pulse turning device includes:

[0008] The main air pipe is fixed inside the housing, with one end extending out of the housing and connected to the pressure stabilizing tank.

[0009] Branch trachea, multiple symmetrically connected to both sides of the main trachea, each branch trachea is provided with several air holes pointing to the support plate;

[0010] The pulse valve is connected to the corresponding air holes through branch pipes;

[0011] A venturi tube is connected to the outlet of the one-way valve;

[0012] The gas pipeline has its inlet end connected to a gas storage tank and its branch ends connected to each of the aforementioned pressure stabilizing tanks.

[0013] The PLC controller controls the opening and closing sequence of the pulse valve.

[0014] Preferably, a pneumatic exhaust valve is used in conjunction with the pulse turning device.

[0015] Preferably, the housing is provided with a slide rail for supporting the support plate.

[0016] Preferably, the support plate has a square open structure with a mesh laid at the open part, and the edge of the support plate is provided with a detachable square pressure frame for fixing the mesh.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] This invention stores high-pressure gas in a gas storage tank. The high-pressure gas enters a pressure stabilizing tank and is distributed to the main gas pipe, and then distributed to the branch gas pipes. When the pressure reaches the set value, it is released by a pulse valve. After the airflow is accelerated and the pressure is converted by the venturi tube, it impacts the material in the bearing plate through the grid holes, causing it to turn over, thereby making the material dry evenly and improving the drying efficiency. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of an air-source heat pump fruit and vegetable dryer.

[0020] Figure 2 This is a schematic diagram of the pulse turning device;

[0021] Figure 3 This is a schematic diagram of the structure of the support plate.

[0022] In the diagram: 1. Shell; 2. Support plate; 3. Pulse turning device; 4. Main air pipe; 5. Pressure stabilizing tank; 6. Branch air pipe; 7. Pulse valve; 8. Venturi tube; 9. One-way valve; 10. Air supply pipe; 11. Air storage tank; 12. Pneumatic exhaust valve; 13. Gauze screen; 14. Square pressure frame. Detailed Implementation

[0023] To make the objectives, technical solutions, and beneficial effects of this utility model clearer, the preferred embodiments of this utility model will be described in detail below to facilitate understanding by those skilled in the art.

[0024] Please see Figures 1 to 3 This embodiment provides an air heat source heat pump fruit and vegetable dryer, including: a shell 1, and a hot air duct system connected to the shell 1. The hot air duct system is existing technology and will not be described in detail in this embodiment, nor will it be shown in the figure.

[0025] The drawer-type support trays 2 are vertically distributed in multiple layers within the housing 1, and a pulse turning device 3 is provided below each layer of the support tray 2; the bottom of the support tray 2 is provided with grid holes; the pulse turning device 3 impacts the material in the support tray 2 through the grid holes, causing it to turn over, thereby making the material dry evenly and improving the drying efficiency.

[0026] The pulse turning device 3 includes:

[0027] The main air pipe 4 is fixed inside the housing 1, with one end extending out of the housing 1 and connected to the pressure stabilizing tank 5. The pressure stabilizing tank 5 is an existing device, whose main function is to ensure the accuracy and consistency of the fruit and vegetable turning action by buffering air pressure fluctuations, filtering impurities, and stabilizing the flow rate.

[0028] Multiple branch air pipes 6 are symmetrically connected to both sides of the main air pipe 4, and each branch air pipe 6 has several air holes pointing to the support plate 2; pulse valves 7 are connected to the air holes one by one through the branch pipes; the pulse valves 7 form an array to uniformly spray the support plate 2. The pulse valves 7 are selected from high temperature resistant types.

[0029] The Venturi tube 8 is connected to the outlet of the one-way valve 9; the one-way valve 9 prevents debris and airflow from flowing back into the pulse valve 7. The Venturi tube 8 utilizes a contraction-expansion pipe structure to increase the velocity of the passing airflow at the throat section (according to Bernoulli's principle, fluid velocity is inversely proportional to the pipe cross-sectional area). Actual measurements show that when the pulse valve 7 releases 0.6 MPa compressed gas, the airflow, accelerated by the Venturi tube 8, can reach an outlet velocity of 80–100 m / s, forming a high-speed jet that penetrates the grid holes of the support plate 2, producing a significant material lifting effect.

[0030] The gas pipeline 10 has its inlet end connected to the gas storage tank 11 and its branch ends connected to each of the pressure stabilizing tanks 5 respectively; the gas storage tank 11 stores high-pressure gas for charging the pulse valve 7.

[0031] The PLC controller controls the opening and closing sequence of the pulse valve 7. The PLC controller sets the ejection air pressure and ejection interval of the pulse valve 7 according to different materials.

[0032] A pneumatic exhaust valve 12 is linked to the pulse turning device 3. When the device is turned by the pulse jet, the pneumatic exhaust valve 12 opens to prevent excessive pressure inside the dryer.

[0033] The housing 1 is provided with a slide rail for supporting the support plate 2.

[0034] The support plate 2 has a square open structure, with a mesh 13 laid at the opening. A detachable square pressure frame 14 is provided along the edge of the support plate 2 to secure the mesh 13. When material is blown up, the mesh 13 intercepts the material, preventing it from splashing. The mesh 13 is made of polytetrafluoroethylene coated fiberglass mesh.

[0035] When using the air-source heat pump fruit and vegetable dryer of this utility model:

[0036] First, the material is laid in the support tray 2, and a mesh screen 13 is laid at the opening and fixed with a square pressure frame 14. The dryer door is closed, and the hot air pipeline system is started. The gas storage tank 11 stores high-pressure gas, which enters the pressure stabilizing tank 5 and is distributed to the main air pipe 4. The main air pipe 4 then distributes the gas to the branch air pipes 6. When the pressure reaches the set value, it is released by the pulse valve 7. After the airflow is accelerated and the pressure is converted by the venturi tube 8, it impacts the material in the support tray 2 through the grid holes, causing it to turn over.

[0037] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although the utility model has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of this utility model.

Claims

1. An air-source heat pump fruit and vegetable dryer, comprising: A housing (1) and a hot air duct system connected to the housing (1) are characterized by having multiple drawer-type support trays (2) vertically distributed in the housing (1) and a pulse turning device (3) located below each support tray (2); the bottom of the support tray (2) is provided with a grid hole; the pulse turning device (3) includes: a main air pipe (4), fixedly located inside the housing (1), with one end extending out of the housing (1) and connected to a pressure stabilizing tank (5); multiple branch air pipes (6), symmetrically connected to both sides of the main air pipe (4), each branch air pipe (6) having several air holes pointing to the support tray (2); a pulse valve (7), connected to the air holes one by one through the branch pipes; a one-way valve (9), located at the outlet of the pulse valve (7); a venturi tube (8), connected to the outlet of the one-way valve (9); and an air supply pipe (10), the inlet end of which is connected to an air storage tank (11), and the branch ends are respectively connected to each of the pressure stabilizing tanks (5). The PLC controller controls the opening and closing sequence of the pulse valve (7).

2. The dryer according to claim 1, characterized in that, Also includes: A pneumatic exhaust valve (12) is linked to the pulse turning device (3).

3. The dryer according to claim 1, characterized in that, The housing (1) is provided with a slide rail for supporting the support plate (2).

4. The dryer according to claim 1, characterized in that, The support plate (2) is a square open structure with a mesh (13) laid at the opening. The edge of the support plate (2) is provided with a detachable square pressure frame (14) for fixing the mesh (13).

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