A control method of an energy-saving management dryer

Abstract

The present application relates to a kind of control methods of energy-saving management dryer, comprising the following steps: after energy-saving management dryer is started, control variable frequency fan to run at high speed;Detection inlet temperature and set drying temperature compared, control drying heating output to heat air fluid;Control variable frequency fan high speed operation pre-set drying time after cycle comparison the temperature difference of dryer inlet and outlet, with pre-set temperature difference value A, and according to the result to control variable frequency fan by high speed or low speed operation;Control variable frequency fan high speed operation pre-set drying time after starting simultaneously cycle comparison the output frequency of variable frequency fan whether it is high speed output frequency, and combine the temperature difference of dryer inlet and outlet with the result of pre-set temperature difference value B, to judge whether to modify variable frequency fan output frequency to control air fluid flow.The present application is compared by temperature difference value A and temperature difference value B, to control variable frequency fan to carry out accurate regulation, realize the premise of high-quality drying under energy saving and environmental protection.

Description

Technical Field

[0001] This invention relates to the field of dryer technology, and in particular to a control method for energy-saving dryers. Background Technology

[0002] A dryer is a mechanical device that uses heat energy to reduce the moisture content of materials. It is used to dry objects by heating the material to vaporize and release the moisture, thereby obtaining solid materials with a specified moisture content.

[0003] Currently, the energy-saving control method for dryers is generally based on the temperature of the air inlet and outlet and the heating time. However, this intelligent control method has a major drawback: it cannot accurately control the actual temperature of the material. Although the heating output power and fan output power have energy-saving effects, the product quality is unstable and the defect rate is increased due to insufficient drying of raw materials, which ultimately leads to greater waste. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a control method for an energy-saving dryer. By comparing the temperature difference between the air inlet and outlet of the dryer with a preset temperature difference value A, and comparing the temperature difference between the air inlet and outlet of the dryer with a preset temperature difference value B, the variable frequency fan is precisely adjusted to reduce the power consumption of heating output and the output power of the variable frequency fan. This achieves energy saving and environmental protection while ensuring drying quality and reducing the power consumption of heating output and the output power of the variable frequency fan.

[0005] The technical solution adopted by the present invention to solve its technical problem is: to provide a control method for an energy-saving dryer, wherein the dryer includes a dryer body and a heating barrel, a discharge temperature sensor is installed at the discharge port at the lower part of the dryer body to detect the temperature of the discharge port, an air outlet temperature sensor is installed at the air outlet at the upper part of the dryer body to detect the temperature of the air outlet, an air inlet temperature sensor is installed at the air inlet of the dryer body to detect the temperature of the air inlet, the air inlet of the dryer body is connected to the air outlet of the heating barrel, and a variable frequency fan and a control box are installed on the heating barrel;

[0006] The control method includes the following steps:

[0007] Step 1: After the energy-saving dryer is started, control the variable frequency fan to run at high speed;

[0008] Step 2: Compare the inlet air temperature with the set drying temperature, and control the drying heating output to heat the airflow.

[0009] Step 3: After controlling the variable frequency fan to run at high speed for the preset drying time, the temperature difference between the air inlet and outlet of the dryer is compared with the preset temperature difference value A. Based on the comparison result, the variable frequency fan is controlled to run at high or low speed. It can automatically reduce the air flow by controlling the frequency of the variable frequency fan to reduce the air flow when the raw material is from cold to the end of drying, thus saving the heating output power and fan output power required to heat the reduced air flow to the set temperature.

[0010] Step 4: After controlling the variable frequency fan to run at high speed for the preset drying time, simultaneously start cyclically judging whether the output frequency of the variable frequency fan is the high speed output frequency, and combine the temperature difference between the air inlet and outlet of the dryer with the preset temperature difference value B to determine whether to correct the output frequency of the variable frequency fan to control the air flow rate.

[0011] As a supplement to the technical solution described in this invention, in step one: the operating frequency of the variable frequency fan at high speed is controlled to be 60Hz.

[0012] As a supplement to the technical solution described in this invention, in step three: the preset drying time is not less than 50% of the drying time provided by the plastic raw material manufacturer.

[0013] As a supplement to the technical solution described in this invention, in step three: the period of comparing the temperature difference between the inlet and outlet of the dryer with the preset temperature difference value A is less than or equal to 60 seconds.

[0014] As a supplement to the technical solution described in this invention, in step three: controlling the variable frequency fan to operate at high or low speed based on the result of comparing the temperature difference between the inlet and outlet of the dryer with a preset temperature difference value A, specifically includes: when the temperature difference between the inlet and outlet is greater than or equal to the preset temperature difference value A, controlling the high-speed output frequency of the variable frequency fan to remain unchanged; when the temperature difference between the inlet and outlet is less than the preset temperature difference value A, controlling the variable frequency fan to operate at low speed, and the operating frequency of the variable frequency fan at low speed is controlled to be 30Hz; wherein, the preset temperature difference value A is 10℃±a, where a is an environmental correction coefficient, 0℃≤a≤5℃.

[0015] As a supplement to the technical solution described in this invention, in step four: the cycle of judging the temperature difference between the air inlet and the outlet of the dryer and the preset temperature difference value B is less than or equal to 300 seconds.

[0016] As a supplement to the technical solution described in this invention, in step four: based on whether the output frequency of the variable frequency fan 3 is a high-speed output frequency, and combined with the result of the temperature difference between the air inlet and outlet of the dryer and the preset temperature difference value B, it is determined whether to correct the output frequency of the variable frequency fan to control the airflow, specifically including:

[0017] When the variable frequency fan is running at a high speed output frequency, no output frequency correction is performed, and the high speed output frequency of the variable frequency fan remains unchanged. When the variable frequency fan is running at a non-high speed output frequency, and the temperature difference between the air inlet and the outlet is greater than or equal to the preset temperature difference value B, the variable frequency fan is controlled to run at an output frequency of 45Hz. When the variable frequency fan is running at a non-high speed output frequency, and the temperature difference between the air inlet and the outlet is less than the preset temperature difference value B, the variable frequency fan is controlled to run at an output frequency of 30Hz.

[0018] Beneficial effects: This invention relates to a control method for an energy-saving dryer. By comparing the temperature difference between the dryer's inlet and outlet with a preset temperature difference value A, and comparing the temperature difference between the dryer's inlet and outlet with a preset temperature difference value B, the variable frequency fan is precisely adjusted. This achieves energy saving and environmental protection while ensuring drying quality, reducing the power consumption of heating output and the output power of the variable frequency fan. Attached Figure Description

[0019] Figure 1 This is a flowchart of the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of the present invention.

[0021] Diagram: 1. Dryer body, 2. Heating tank, 3. Variable frequency fan, 4. Control box, 5. Inlet air temperature sensor, 6. Outlet air temperature sensor, 7. Outlet material temperature sensor. Detailed Implementation

[0022] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0023] Embodiments of the present invention relate to a control method for an energy-saving dryer, such as... Figure 1-2As shown, the dryer includes a dryer body 1 and a heating tank 2. A discharge temperature sensor 7 is installed at the discharge port at the lower part of the dryer body 1 to detect the temperature of the discharge port. An air outlet temperature sensor 6 is installed at the air outlet at the upper part of the dryer body 1 to detect the temperature of the air outlet. An air inlet temperature sensor 5 is installed at the air inlet of the dryer body 1 to detect the temperature of the air inlet. The air inlet of the dryer body 1 is connected to the air outlet of the heating tank 2. A variable frequency fan 3 and a control box 4 are installed on the heating tank 2.

[0024] The control box 4 is connected to the discharge temperature sensor 7, the air outlet temperature sensor 6, the air inlet temperature sensor 5, the heating tank 2, and the variable frequency fan 3 respectively. The temperature data detected by the discharge temperature sensor 7, the air outlet temperature sensor 6, and the air inlet temperature sensor 5 are transmitted to the control box 4. After processing, the control box 4 controls the heating tank 2 and the variable frequency fan 3 to make adjustments respectively.

[0025] The control method includes the following steps:

[0026] Step 1: After the energy-saving dryer is started, control the variable frequency fan 3 to run at high speed;

[0027] Step 2: Compare the inlet air temperature with the set drying temperature, and control the drying heating output to heat the airflow.

[0028] Step 3: After controlling the variable frequency fan 3 to run at high speed for the preset drying time, the temperature difference between the air inlet and outlet of the dryer is compared with the preset temperature difference value A. Based on the comparison result, the variable frequency fan 3 is controlled to run at high or low speed. Therefore, when the raw material is from cold to the end of drying, the frequency of the variable frequency fan 3 is automatically reduced to reduce the air flow rate, saving the heating output power and fan output power required to heat the reduced air flow rate to the set temperature, thereby achieving the purpose of energy saving.

[0029] Step 4: After controlling the variable frequency fan 3 to run at high speed for the preset drying time, simultaneously start cyclically judging whether the output frequency of the variable frequency fan is the high speed output frequency, and combine the temperature difference between the air inlet and outlet of the dryer with the preset temperature difference value B to determine whether to correct the output frequency of the variable frequency fan 3 to control the air flow rate.

[0030] As a preferred embodiment of the present invention, in step one: the operating frequency of the variable frequency fan 3 at high speed is controlled to be 60Hz; during the initial drying stage after startup, the variable frequency fan is controlled to operate at high speed (60Hz) to obtain a higher airflow rate than the standard operating fan (50Hz) of the same specification to dry the raw materials in the dryer, resulting in faster drying speed and higher drying efficiency.

[0031] As a preferred embodiment of the present invention, in step three: the preset drying time is not less than 50% of the drying time provided by the plastic raw material manufacturer.

[0032] As a preferred embodiment of the present invention, in step three, the period of comparing the temperature difference between the inlet and outlet of the dryer with the preset temperature difference value A is less than or equal to 60 seconds.

[0033] In a preferred embodiment of the present invention, step three, which involves controlling the variable frequency fan 3 to operate at high or low speed based on the temperature difference between the inlet and outlet of the dryer and a preset temperature difference value A, specifically includes:

[0034] When the temperature difference between the air inlet and outlet is greater than or equal to the preset temperature difference value A, the high-speed output frequency of the variable frequency fan 3 is kept constant.

[0035] When the temperature difference between the air inlet and outlet is less than the preset temperature difference value A, the variable frequency fan 3 is controlled to run at a low speed, and the operating frequency of the variable frequency fan 3 is controlled to be 30Hz at the low speed.

[0036] The preset temperature difference value A is 10℃±a, where a is an environmental correction factor, and 0℃≤a≤5℃.

[0037] As a preferred embodiment of the present invention, in step four: the cycle of judging the temperature difference between the air inlet and the outlet of the dryer and the preset temperature difference value B is less than or equal to 300 seconds.

[0038] As a preferred embodiment of the present invention, in step four: based on whether the output frequency of the variable frequency fan 3 is a high-speed output frequency, and combined with the result of the temperature difference between the air inlet and outlet of the dryer and the preset temperature difference value B, it is determined whether to correct the output frequency of the variable frequency fan 3 to control the air flow rate, specifically including:

[0039] When the variable frequency fan 3 is running at a high speed output frequency, no output frequency correction is performed, and the high speed output frequency of the variable frequency fan 3 is kept constant.

[0040] When the variable frequency fan 3 is running at a non-high speed output frequency, and when the temperature difference between the air inlet and the outlet is greater than or equal to the preset temperature difference value B, the variable frequency fan 3 is controlled to run at an output frequency of 45Hz.

[0041] When the variable frequency fan 3 is running at a non-high speed output frequency, and when the temperature difference between the air inlet and the outlet is less than the preset temperature difference value B, the variable frequency fan 3 is controlled to run at an output frequency of 30Hz.

[0042] This invention controls the variable frequency fan 3 to make precise adjustments by comparing the temperature difference between the air inlet and outlet of the dryer with the preset temperature difference value A, and comparing the temperature difference between the air inlet and outlet of the dryer with the preset temperature difference value B. This achieves energy saving and environmental protection while ensuring drying quality, reducing the power consumption of heating output and the output power of the variable frequency fan 3.

[0043] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0044] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0045] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0046] The control method for an energy-saving dryer provided in this application has been described in detail above. Specific examples have been used to illustrate the principle and implementation of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​this application. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A control method of an energy-saving management dryer, the dryer comprising a dryer main body (1) and a heating tub (2), characterized in that: A discharge temperature sensor (7) is installed at the discharge port at the lower part of the dryer body (1). The discharge temperature sensor (7) is used to detect the temperature of the discharge port. An air outlet temperature sensor (6) is installed at the air outlet at the upper part of the dryer body (1). The air outlet temperature sensor (6) is used to detect the temperature of the air outlet. An air inlet temperature sensor (5) is installed at the air inlet of the dryer body (1). The air inlet of the dryer body (1) is used to detect the temperature of the air inlet. The air inlet of the dryer body (1) is connected to the air outlet of the heating tank (2). A variable frequency fan (3) and a control box (4) are installed on the heating tank (2). The control method includes the following steps: Step 1: After the energy-saving dryer is started, control the variable frequency fan (3) to run at high speed; Step 2: Compare the inlet air temperature with the set drying temperature, and control the drying heating output to heat the airflow. Step 3: Control the variable frequency fan (3) to run at high speed. After the preset drying time, compare the temperature difference between the air inlet and outlet of the dryer with the preset temperature difference value A, and control the variable frequency fan (3) to run at high speed or low speed according to the comparison result. It can automatically reduce the air flow by controlling the frequency of the variable frequency fan (3) when the raw material is from cold material to the completion of drying, thereby saving the heating output power and fan output power required to heat the reduced air flow to the set temperature. Step 4: Control the variable frequency fan (3) to run at high speed. After the preset drying time, start the cycle to judge whether the output frequency of the variable frequency fan is the high speed output frequency. Combine the temperature difference between the air inlet and outlet of the dryer with the preset temperature difference value B to determine whether to correct the output frequency of the variable frequency fan (3) to control the air flow rate. In step four: based on whether the output frequency of the variable frequency fan (3) is a high-speed output frequency, and combined with the result of the temperature difference between the air inlet and outlet of the dryer and the preset temperature difference value B, it is determined whether to correct the output frequency of the variable frequency fan (3) to control the air flow rate, specifically including: When the variable frequency fan (3) is running at a high speed output frequency, no output frequency correction is performed, and the high speed output frequency of the variable frequency fan (3) is kept unchanged. When the variable frequency fan (3) is running at a non-high speed output frequency, and when the temperature difference between the air inlet and the outlet is greater than or equal to the preset temperature difference value B, the variable frequency fan (3) is controlled to run at an output frequency of 45Hz. When the variable frequency fan (3) is running at a non-high speed output frequency, and when the temperature difference between the air inlet and the outlet is less than the preset temperature difference value B, the variable frequency fan (3) is controlled to run at an output frequency of 30Hz.

2. The control method of an energy-saving management dryer according to claim 1, characterized in that: In step one, the operating frequency of the variable frequency fan (3) at high speed is controlled to be 60Hz.

3. The control method of an energy-saving management dryer according to claim 1, characterized in that: In step three, the preset drying time is no less than 50% of the drying time provided by the plastic raw material manufacturer.

4. The control method for an energy-saving dryer according to claim 1, characterized in that: In step three, the period of comparing the temperature difference between the inlet and outlet of the dryer with the preset temperature difference value A is less than or equal to 60 seconds.

5. The control method for an energy-saving dryer according to claim 1, characterized in that: In step three, the variable frequency fan (3) is controlled to operate at high or low speed based on the temperature difference between the inlet and outlet of the dryer and the preset temperature difference value A. Specifically, this includes: When the temperature difference between the air inlet and outlet is greater than or equal to the preset temperature difference value A, the high-speed output frequency of the variable frequency fan (3) is kept constant. When the temperature difference between the air inlet and outlet is less than the preset temperature difference value A, the variable frequency fan (3) is controlled to run at a low speed. When the speed is low, the operating frequency of the variable frequency fan (3) is controlled to be 30Hz. The preset temperature difference value A is 10℃±a, where a is an environmental correction coefficient, 0℃≤a≤5℃.

6. The control method for an energy-saving dryer according to claim 1, characterized in that: In step four, the cycle of judging the temperature difference between the air inlet and the outlet of the dryer and the preset temperature difference value B is less than or equal to 300 seconds.

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