Valve and control method

Abstract

The application discloses a valve and a control method, wherein the valve comprises a valve body, a temperature sensor for detecting the real-time temperature of the valve body, a switch executing unit for driving the valve rod to rotate to adjust the opening degree of the valve, a current sensor for detecting the working current of the switch executing unit when the valve rod is driven to rotate, and a control unit for determining whether the real-time temperature is lower than a temperature threshold value, and if yes, controlling the switch executing unit to be sequentially forward rotated and reverse rotated to make the valve rod rotate, and the control unit also determines whether the valve rod is frozen according to the working current and historical current, and if yes, the control unit shortens the time interval of the switch executing unit. When the valve rod is frozen, the application timely increases the operation frequency to prevent the valve rod from being frozen by high-frequency rotation, and effectively ensures the reliability of the valve.

Description

Technical Field

[0001] This application relates to the field of industrial control technology, and in particular to a valve and control method. Background Technology

[0002] Valves are control switches for the flow of fluids in pipelines. They are widely used in various industrial fields, and the normal operation of valves has a crucial impact on industrial production.

[0003] Although valves consist of multiple components, these components are mostly stationary, making them susceptible to freezing in low-temperature environments. This can lead to poor switching and negatively impact industrial production. Currently, there is no solution to valve freezing. Summary of the Invention

[0004] This application provides a valve and control method to solve the problem of valves easily freezing and clogging in low-temperature environments in the prior art.

[0005] On one hand, embodiments of this application provide a valve, including:

[0006] The valve body has a valve stem that rotates inside.

[0007] A temperature sensor, located inside the valve body, is used to detect the real-time temperature of the valve body.

[0008] The switching actuator is connected to the valve stem and is used to drive the valve stem to rotate in order to adjust the valve opening.

[0009] A current sensor is used to detect the operating current when the switch actuator drives the valve stem to rotate;

[0010] The control unit is communicatively connected to both the temperature sensor and the switching actuator. After obtaining the real-time temperature, the control unit determines whether the real-time temperature is lower than the temperature threshold. If so, it controls the switching actuator to rotate forward and reverse sequentially to make the valve stem rotate. At the same time, the control unit also compares the operating current with the historical current to determine whether the valve stem is frozen. If freezing occurs, the control unit shortens the time interval of the switching actuator.

[0011] On the other hand, embodiments of this application also provide a valve control method, including:

[0012] Detect the real-time temperature of the valve body and the operating current of the switching actuator when it drives the valve stem to rotate;

[0013] Determine if the real-time temperature is below the temperature threshold. If so, control the switch execution unit to rotate forward and then reverse sequentially to make the valve stem rotate.

[0014] The operating current is compared with the historical current to determine whether the valve stem is frozen. If freezing occurs, the time interval of the switching actuator is shortened.

[0015] The valve and control method disclosed in this application have the following advantages:

[0016] When the valve body temperature is below the temperature threshold, the valve stem is driven to rotate continuously in both forward and reverse directions. During the rotation, the operating current is detected, and the valve stem is checked for freezing based on the operating current. If freezing occurs, the time interval between valve stem rotations is shortened to drive the valve stem to rotate before freezing occurs. By rotating at a higher frequency, freezing of the valve stem is prevented, effectively ensuring the reliability of the valve. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of the valve composition provided in the embodiments of this application;

[0019] Figure 2 A flowchart of a valve control method provided in an embodiment of this application. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] Figure 1 This is a schematic diagram illustrating the composition of a valve according to an embodiment of this application. This application provides a valve comprising:

[0022] The valve body has a valve stem that rotates inside.

[0023] A temperature sensor, located inside the valve body, is used to detect the real-time temperature of the valve body.

[0024] The switching actuator is connected to the valve stem and is used to drive the valve stem to rotate in order to adjust the valve opening.

[0025] A current sensor is used to detect the operating current when the switch actuator drives the valve stem to rotate;

[0026] The control unit is communicatively connected to both the temperature sensor and the switching actuator. After obtaining the real-time temperature, the control unit determines whether the real-time temperature is lower than the temperature threshold. If so, it controls the switching actuator to rotate forward and reverse sequentially to make the valve stem rotate. At the same time, the control unit also compares the operating current with the historical current to determine whether the valve stem is frozen. If freezing occurs, the control unit shortens the time interval of the switching actuator.

[0027] For example, the temperature threshold in this application is -10°C. The temperature sensor can directly contact the valve body to detect the real-time temperature of the valve body, or contact the fluid inside the valve body to indirectly infer the real-time temperature of the valve body by detecting the temperature of the fluid.

[0028] The switch actuator is located outside the valve body. Specifically, it can be a stepper motor. The shaft of the stepper motor extends into the valve body and is connected to the end of the valve stem. When the stepper motor is powered on, it starts to rotate and drives the valve stem to rotate, thereby adjusting the valve opening.

[0029] A current sensor can be connected to the power supply line of the switching actuator to determine the operating current of the switching actuator by detecting the current flowing through the power supply line. In the embodiments of this application, since the valve stem rotates forward and backward under the control of the switching actuator, the current sensor needs to detect the operating current in all rotation directions of the switching actuator to meet the needs of subsequent processing.

[0030] Since the signals detected by the temperature sensor and the current sensor are both analog signals, they need to be filtered, amplified, and converted from analog to digital by a signal conditioning circuit to form a high-quality digital signal before being input into the control unit so that the control unit can recognize it correctly.

[0031] The control unit can also be located outside the valve body. Specifically, a protective shell can be installed on the outer surface of the valve body, and the control unit can be installed inside the protective shell. A data interface can also be installed on the protective shell. This data interface communicates with the control unit and can be used to connect an external data writing device for debugging and data writing of the control unit.

[0032] It should be understood that the control unit controls the switch actuator to rotate by the same angle in both forward and reverse directions, so that the valve stem is in the same position as before rotation after it finishes rotating. In the embodiments of this application, the switch actuator drives the valve stem to rotate by 5% of the maximum rotation angle of the valve stem, that is, both the forward and reverse rotation angles are 5% of the maximum rotation angle of the valve stem.

[0033] When determining whether the valve stem is frozen, the control unit can calculate the difference between the operating current and the historical current. If the difference is not zero and the operating current is greater than or equal to the historical current, it can be determined that the valve stem is frozen; otherwise, it can be determined that the valve stem is not frozen.

[0034] Furthermore, the operating current includes the current valve closing current and the current valve opening current. The control unit first determines whether the current valve closing current and the current valve opening current are the same. If they are the same, it indicates that the valve stem has not been frozen. If they are not the same, the operating current is then compared with the historical current.

[0035] The forward and reverse rotation described in this application can be achieved using a control sequence of closing the valve before opening it or opening the valve before closing it. When the valve-closing-then-opening control method is used, the operating current is the current valve-closing current, and the historical current is the historical valve-closing current. The control unit compares the current valve-closing current with the historical valve-closing current to determine whether the valve stem has become frozen. Specifically, the control unit first needs to determine whether the current valve-opening current is greater than the current valve-closing current. If so, it then determines whether the current valve-closing current is greater than or equal to the historical valve-closing current. If so, it is determined that the valve stem has become frozen. If the current valve-opening current is less than or equal to the current valve-closing current, or if the current valve-closing current is less than the historical valve-closing current, it can be determined that the valve stem has not become frozen.

[0036] When using a control method that opens the valve first and then closes it, the operating current is the current valve opening current, and the historical current is the historical valve opening current. The control unit compares the current valve opening current with the historical valve opening current to determine whether the valve stem has become frozen. Specifically, the control unit first needs to determine whether the current valve closing current is greater than the current valve opening current. If so, it then determines whether the current valve opening current is greater than or equal to the historical valve opening current. If so, the valve stem is determined to be frozen. If the current valve closing current is less than or equal to the current valve opening current, or if the current valve opening current is less than the historical valve opening current, then the valve stem is determined not to be frozen.

[0037] When the control unit shortens the time interval of the switching execution unit, it can use half of the original time interval as the new time interval and store it in the storage unit. The control unit can then control the rotation of the valve stem according to the updated event interval.

[0038] In one possible embodiment, after determining that the real-time temperature is below the temperature threshold, the control unit also retrieves the stored interval time data from the storage unit and determines whether the interval time data is zero. If it is not zero, the control unit then controls the switch execution unit to rotate.

[0039] For example, the storage unit can be housed within the protective casing along with the control unit to store manually input interval time data, which can be set by the operator as needed. If the set interval time data is zero, it indicates that the current anti-freeze operation has not been activated, and the control unit can proceed with the next temperature check.

[0040] In the embodiments of this application, when the interval time data is not zero, the control unit counts down according to the interval time data, and controls the switch execution unit to rotate when the countdown reaches zero.

[0041] It should be understood that when the valve stem rotates under the drive of the switching actuator, there is a time interval between forward and reverse rotation. The length of this time interval will also affect the effectiveness of the anti-freezing operation. If the time interval is too long, the valve stem may freeze again after rotating forward. When it reverses again, the working current generated may be greater than the working current of forward rotation, causing the working current to fail to accurately reflect the freezing status. Therefore, the event interval between forward and reverse rotation of the valve stem should be much smaller than the time interval between two rotations of the valve stem.

[0042] Furthermore, if the valve stem is not frozen, the control unit resumes the interval. Specifically, if the current opening and closing currents are the same, or if the difference between the operating current and the historical current is zero, it can be determined that the valve stem is not frozen.

[0043] This application also provides a valve control method, such as... Figure 2 As shown, the method includes the following steps:

[0044] S200 detects the real-time temperature of the valve body and the operating current when the switching actuator drives the valve stem to rotate;

[0045] S210, determine whether the real-time temperature is lower than the temperature threshold. If so, control the switch execution unit to rotate forward and reverse sequentially to make the valve stem rotate.

[0046] S220 compares the operating current with the historical current to determine if the valve stem is frozen. If freezing occurs, the time interval of the switching actuator is shortened.

[0047] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0048] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A valve, characterized in that, include: The valve body has a valve stem that rotates inside. A temperature sensor is installed inside the valve body to detect the real-time temperature of the valve body; A switching actuator is connected to the valve stem, and the switching actuator is used to drive the valve stem to rotate in order to adjust the opening degree of the valve; A current sensor is used to detect the operating current when the switch actuator drives the valve stem to rotate; The control unit is communicatively connected to both the temperature sensor and the switch execution unit. After acquiring the real-time temperature, the control unit determines whether the real-time temperature is lower than the temperature threshold. If so, it controls the switch execution unit to rotate forward and reverse sequentially to make the valve stem rotate. At the same time, the control unit also compares the operating current with the historical current to determine whether the valve stem is frozen. If freezing occurs, the control unit shortens the time interval of the switch execution unit. When the control method of closing the valve first and then opening the valve is adopted, the working current is the valve closing current of this time, and the historical current is the historical valve closing current. The control unit first determines whether the valve opening current of this time is greater than the valve closing current of this time. If it is, it then determines whether the valve closing current of this time is greater than the historical valve closing current. If it is, it is determined that the valve stem has been frozen. When the control method of opening the valve first and then closing the valve is adopted, the working current is the valve opening current of this time, and the historical current is the historical valve opening current. The control unit first determines whether the valve closing current of this time is greater than the valve opening current of this time. If so, it then determines whether the valve opening current of this time is greater than the historical valve opening current. If so, it is determined that the valve stem has been frozen.

2. The valve according to claim 1, characterized in that, After determining that the real-time temperature is lower than the temperature threshold, the control unit also retrieves the stored interval time data from the storage unit and determines whether the interval time data is zero. If it is not zero, the control unit then controls the switch execution unit to rotate.

3. A valve according to claim 2, characterized in that, When the interval time data is not zero, the control unit counts down according to the interval time data, and controls the switch execution unit to rotate when the countdown reaches zero.

4. A valve according to claim 3, characterized in that, If the valve stem is not frozen, the control unit resumes the interval.

5. A valve according to claim 1, characterized in that, The control unit controls the switch execution unit to rotate at the same angle in both forward and reverse directions, so that the valve stem is in the same position as before rotation after it stops rotating.

6. A method for controlling a valve, said method being applied to the valve of claim 1, characterized in that, include: Detect the real-time temperature of the valve body and the operating current of the switching actuator when it drives the valve stem to rotate; Determine whether the real-time temperature is lower than the temperature threshold. If so, control the switch execution unit to rotate forward and reverse sequentially to make the valve stem rotate. The operating current is compared with the historical current to determine whether the valve stem is frozen. If freezing occurs, the time interval of the switching actuation unit is shortened.

Images