Control system for moving parts

Abstract

This application discloses a control system for a moving component. The control system includes: a position determination unit for determining the position of the moving component; a drive unit for driving the moving component, wherein the drive unit includes a motor and a frequency converter, and the motor is an asynchronous motor or a synchronous motor; and a control unit for controlling the moving component via the drive unit based on the position determined by the position determination unit. This reduces the control cost of the moving component.

Description

Technical Field

[0001] This application relates to the field of motion control technology, and more specifically, to a control system for a moving part. Background Technology

[0002] The civil aircraft fire suppression test bench is used to conduct tests and research on fire characteristics, smoke spread, and fire suppression effectiveness. During the test, a rain rake is required to simulate a rainfall environment. Due to space limitations in the test chamber, the rain rake must have reciprocating movement and positioning capabilities.

[0003] The existing rake control method has obvious drawbacks. The existing rake control method uses servo motors, servo drivers and encoders to achieve position control, which results in high hardware costs and expensive system construction.

[0004] Therefore, how to reduce the control cost of rain rakes has become a technical problem that needs to be solved in this field. Summary of the Invention

[0005] In view of this, this application proposes a control system for moving parts to reduce the control cost of moving parts.

[0006] According to this application, a control system for a moving part is proposed, the control system comprising: a position determination unit for determining the position of the moving part; a drive unit for driving the moving part, wherein the drive unit includes a motor and a frequency converter, the motor being an asynchronous motor or a synchronous motor; and a control unit for controlling the moving part through the drive unit according to the position determined by the position determination unit.

[0007] Optionally, the control system further includes a fixing unit for fixing the moving part after the moving part reaches a preset position.

[0008] Optionally, the fixing unit is an electromagnet.

[0009] Optionally, the position determination unit includes: a forward positioning limit for determining the position where the moving component needs to stop moving when moving towards the target; a deceleration limit for determining the position where the moving component needs to decelerate; and a backward positioning limit for determining the position where the moving component needs to stop moving when moving away from the target. The control unit is configured to: control the moving component to stop moving via the drive unit upon receiving a signal from the forward positioning limit or the backward positioning limit; and control the moving component to decelerate via the drive unit upon receiving a signal from the deceleration limit.

[0010] Optionally, the position determination unit further includes: a forward limit stop, used to determine the maximum position that the moving component can reach when moving towards the target; and a backward limit stop, used to determine the maximum position that the moving component can retreat to when moving away from the target; wherein, the control unit is further used to: control the moving component to stop moving via the drive unit when receiving a signal from the forward limit stop or the backward limit stop.

[0011] Optionally, the moving component is a rain rake, and the position determining unit further includes: a leg allowable movement limiter, used to determine the position of the leg extending and retracting; wherein, the control unit is further used to: when receiving a signal from the leg allowable movement limiter during the forward movement of the rain rake, control the rain rake to extend the leg through the drive unit; and when receiving a signal from the leg allowable movement limiter during the backward movement of the rain rake, control the rain rake to retract the leg through the drive unit.

[0012] Optionally, the control unit is further configured to: control the motor to rotate forward via the frequency converter when a forward command is received; and control the motor to rotate in reverse via the frequency converter when a backward command is received.

[0013] Optionally, the moving component is a rain rake, and the control system further includes: a door opening determination unit, used to determine whether the forward door of the fire extinguishing test platform is open; the control unit is also used to: upon receiving a forward command, if the door opening determination unit determines that the forward door of the fire extinguishing test platform is open, then control the rain rake to move toward the fire extinguishing test platform.

[0014] Optionally, the control system further includes an STO safety circuit for issuing an emergency stop signal; wherein the control unit is further configured to: control the moving part to stop urgently upon receiving the emergency stop signal issued by the STO safety circuit.

[0015] Optionally, the control unit is further configured to: control the motor to stop immediately in the event of motor overload, overcurrent, or overheating.

[0016] According to the technical solution of this application, the control system includes a position determination unit, a drive unit, and a control unit. The position determination unit determines the position of the moving part, and the control unit controls the moving part through the drive unit based on the position determined by the position determination unit. The drive unit includes a motor and a frequency converter; the motor can be an asynchronous motor or a synchronous motor. This achieves control of the moving part. Furthermore, when controlling the moving part, a combination of the position determination unit, frequency converter, asynchronous or synchronous motor, and control unit is used, eliminating the need for a servo motor combined with a servo driver. The position determination unit, frequency converter, asynchronous or synchronous motor have lower costs, thereby reducing the control cost of the moving part.

[0017] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application, and the illustrative embodiments and descriptions thereof are used to explain this application. In the drawings: Figure 1 This is a structural block diagram of the control system for a moving component according to a preferred embodiment of this application; Figure 2 This is a schematic diagram of each limiting position according to a preferred embodiment of this application; Figure 3 This is a schematic diagram of the control logic of a rain rake according to a preferred embodiment of this application. Detailed Implementation

[0019] The technical solution of this application will now be described in detail with reference to the accompanying drawings and embodiments.

[0020] This application provides a control system for a moving component. The moving component can be a component that can be driven by a motor and a frequency converter.

[0021] Figure 1 This is a structural block diagram of a control system for a moving component according to a preferred embodiment of this application. Figure 1 As shown, the control system includes a position determination unit 10, a control unit 20, and a drive unit 30.

[0022] The position determination unit 10 is used to determine the position of the moving part.

[0023] The drive unit 30 is used to drive the moving parts.

[0024] The drive unit 30 includes a motor and a frequency converter. The motor can be an asynchronous motor or a synchronous motor. The control unit 20 is connected to the frequency converter, and the output of the frequency converter is connected to the asynchronous motor or the synchronous motor. For example, it can be a standard three-phase asynchronous motor combined with a general-purpose frequency converter.

[0025] The control unit 20 is used to control the moving part through the drive unit 30 according to the position determined by the position determination unit 10.

[0026] Optionally, the control unit 20 can be a PLC. For example, a Siemens PLC can be used. Specifically, it can be a Siemens S7 series PLC.

[0027] Optionally, the PLC connects to the frequency converter via control words or speed words to realize the start / stop, direction, and speed adjustment of the frequency converter. When the PLC receives a motor start command, it determines whether to control the motor to rotate forward or backward based on whether the command is forward or backward. After determining this, it sets the speed, and it is recommended to set the speed value to half of the fastest speed, starting from zero and accelerating, and then drive the motor through the frequency converter output.

[0028] Optionally, in this embodiment, the inverter can be selected as a V / F control mode, with a constant voltage / frequency ratio. The V / F control mode maintains constant magnetic flux by synchronously adjusting the voltage and frequency ratio. This is suitable for applications such as fans and pumps where speed range requirements are not high, but voltage compensation is needed to increase torque at low speeds.

[0029] Using V / F control as the core control method, it can maintain constant magnetic flux by synchronously adjusting the voltage and frequency ratio; it automatically performs voltage compensation at low speeds to ensure output torque; it has strong versatility, supports all standard frequency converters, and has the lowest hardware cost.

[0030] Optionally, in this embodiment, the frequency converter can be three-phase or single-phase, depending on the specific circumstances. Furthermore, if conditions permit, a frequency converter supporting industrial communication can be selected.

[0031] Regarding the frequency range of the inverter, a minimum frequency (to ensure heat dissipation) and a maximum frequency (to avoid overspeed damage) can be set. In addition, the acceleration and deceleration time of the inverter can be adjusted according to the load inertia (generally 15s acceleration / 5s deceleration reference value) to prevent overcurrent during start-stop and to prevent overcurrent tripping.

[0032] For motors, accurately input the nameplate data such as rated power, voltage, current, and frequency to ensure that the protection functions are effective; In addition, for special scenarios, the "output phase loss protection" function of single-phase motors must be turned off.

[0033] Optionally, the control system also includes a fixing unit. The fixing unit is used to fix the moving part after it reaches a preset position. The preset position can be a position where it is required to stop moving. The preset position can be determined according to specific circumstances and is not limited thereto. Fixing the moving part with the fixing unit after it reaches the preset position can prevent the moving part from shaking or tipping over.

[0034] Alternatively, the fixing unit can be an electromagnet.

[0035] Optionally, the position determination unit 10 includes a forward positioning limit 101, a deceleration limit 102, and a backward positioning limit 103. For example... Figure 2 As shown. The forward positioning limit 101 is closer to the target, namely the fire extinguishing test bench, than the backward positioning limit 103. The deceleration limit 102 is located between the forward positioning limit 101 and the backward positioning limit 102. It should be noted that the target toward which the moving parts are oriented can be determined according to specific circumstances, and there are no restrictions on this.

[0036] The forward stop limit 101 is used to determine the position where the moving part needs to stop moving when advancing towards the target. When the control unit 20 receives a signal from the forward stop limit 101, it indicates that the moving part has reached the position where it needs to stop moving forward.

[0037] Optionally, in this embodiment, the preset position can be the position where the movement needs to stop when moving towards the target, controlled by the forward positioning limit 101. The fixing unit can be an electromagnet, which attracts the moving part to prevent it from tipping over. Specifically, upon receiving the signal from the forward positioning limit 101, the control unit 20 controls the inverter to stop output to control the moving part to stop moving, and controls the electromagnet to engage and lock.

[0038] The deceleration limit switch 102 is used to determine the position where the moving part needs to decelerate. When the control unit 20 receives a signal from the deceleration limit switch 102, it indicates that the moving part has reached the position where it needs to decelerate.

[0039] The reversing limit switch 103 is used to determine the position where the moving part should stop moving when it moves away from the target. When the control unit 20 receives a signal from the reversing limit switch 103, it indicates that the moving part has reached the position where it should stop moving when reversing.

[0040] The control unit 20 is used to control the moving part to stop moving by the drive unit 30 when it receives a signal from the forward positioning limit 101 or the backward positioning limit 103; and to control the moving part to decelerate by the drive unit 30 when it receives a signal from the deceleration limit 102.

[0041] Optionally, the position determining unit 10 may further include a forward limit stop 104 and a backward limit stop 105. For example... Figure 2 As shown, the forward limit stop 104 is closer to the target than the forward positioning stop 101, while the backward limit stop 105 is farther from the target than the backward positioning stop 103. Specifically, the positions of the forward limit stop 104 and the backward limit stop 105 can be determined according to specific circumstances. Figure 2As shown, the backward limit stop 105 and the backward positioning stop 103 are adjacent to each other and are placed side by side.

[0042] By setting forward limit switch 104 and backward limit switch 105, safety can be improved and the solution can be made more reliable.

[0043] The forward limit switch 104 is used to determine the maximum position that the moving part can reach when moving towards the target. When the control unit 20 receives a signal from the forward limit switch 104, it indicates that the moving part has reached the maximum position that it can reach when moving forward.

[0044] The backward limit switch 105 is used to determine the extreme position that the moving part can retreat to when it is away from the target. When the control unit 20 receives a signal from the backward limit switch 105, it indicates that the moving part has reached the extreme position that it can retreat to.

[0045] When the control unit 20 receives a signal from the forward limit switch 104 or the backward limit switch 105, it controls the moving part to stop moving via the drive unit 30.

[0046] Optionally, the moving part can be a rain rake (the rain rake of this project), and the position determining unit 10 may further include a leg-permitting motion limit 106. The leg-permitting motion limit 106 is used to determine the position of the outrigger extension and retraction. In this application, the leg-permitting motion limit 106 may be closer to the target than the deceleration limit 102, such as... Figure 2 As shown. In this application, the fire extinguisher includes multiple nozzles that spray water to extinguish the fire. Specifically, the fire extinguisher has a rectangular frame, within which five lines are placed horizontally and five lines are placed vertically, with a nozzle placed at each intersection of the horizontal and vertical lines.

[0047] The control unit 20 is also used to control the rain rake to extend its outriggers via the drive unit 30 when it receives a signal from the outriggers' permitted action limit 106 during the forward movement of the rain rake; and to control the rain rake to retract its outriggers via the drive unit 30 when it receives a signal from the outriggers' permitted action limit 106 during the backward movement of the rain rake.

[0048] After completing the extension or retraction of the outriggers, the vehicle continues to move. The outrigger linkage logic may include the following: During forward movement, upon receiving the outrigger permission limit 106 signal, the rake pauses, the outriggers extend, and forward movement continues. During backward movement, upon receiving the outrigger permission limit 106 signal, the rake pauses, the outriggers retract, and backward movement continues.

[0049] During forward movement, after the outriggers extend, confirm that they are fully extended. If the outriggers are fully extended, press the forward button again. The controller will receive the forward command again and continue moving forward. Similarly, during backward movement, after the outriggers retract, confirm that they are fully retracted. If the outriggers are fully retracted, press the backward button again. The controller will receive the backward command again and continue moving backward.

[0050] Optionally, the control unit 20 is further configured to control the motor to rotate forward via the frequency converter when a forward command is received, and to control the motor to rotate in reverse via the frequency converter when a backward command is received. Specifically, when a forward command is received, a forward rotation coefficient is assigned to the frequency converter; when a backward command is received, a reverse rotation coefficient is assigned to the frequency converter. When the moving part is stopped, no value is assigned to the frequency converter.

[0051] After assigning a forward or reverse rotation coefficient to the frequency converter, start the motor and run it at the set speed.

[0052] Optionally, the moving component can be a rain rake, and the control system also includes a door opening determination unit 40. The door opening determination unit 40 is used to determine whether the forward door of the fire extinguishing test bench is open.

[0053] The control unit 20 is also configured to, upon receiving a forward command, control the rain rake to move toward the fire extinguishing test platform if the door opening determination unit 40 determines that the forward door of the fire extinguishing test platform is open. If, upon receiving a forward command, the control unit 20 fails to determine that the forward door of the fire extinguishing test platform is open according to the door opening determination unit 40, it will not control the rain rake to move toward the fire extinguishing test platform.

[0054] By setting the door opening determination unit 40, the rain rake is controlled to move towards the fire extinguishing test platform only when the front door is open, and not when the front door is closed, so as to prevent accidental collision with the fire extinguishing test platform.

[0055] Optionally, the door opening determining unit 40 can be a door opening limit 401, such as... Figure 2 As shown. If the control unit 20 receives a signal from the door opening limit 401, it can determine that the front door has been opened; if it does not receive a signal from the door opening limit 401, it can determine that the front door has not been opened.

[0056] Optionally, the control system also includes an STO safety circuit. The STO safety circuit is used to issue an emergency stop signal. The control unit 20 is also used to control the moving parts to stop urgently upon receiving an emergency stop signal from the STO safety circuit. An STO safety port is provided, which receives the emergency stop signal and immediately cuts off the inverter output upon triggering.

[0057] Optionally, the control unit is also used to control the motor to stop immediately in case of motor overload, overcurrent, or overheating. Immediate shutdown in case of motor overload, overcurrent, or overheating prevents equipment damage.

[0058] Optionally, in the embodiments of this application, various limit switches can be limit switches, proximity switches, photoelectric switches, etc.

[0059] Optionally, the control system also includes a communication unit. The communication unit supports communication control between the control unit 20 and the frequency converter. For example, the communication unit can be an analog signal or a bus signal.

[0060] Figure 3 This is a schematic diagram of the control logic of a rain rake according to a preferred embodiment of this application. (In conjunction with...) Figure 3 The control process of the rain rake is described exemplarily.

[0061] The system determines whether to control the rake to move forward or backward. When the operator presses the forward or backward button, a forward or backward command is sent to the PLC. The PLC then determines whether to control the rake to move forward or backward based on the received command.

[0062] While controlling the rake's forward movement, assign a forward rotation coefficient to the frequency converter. Start the frequency converter. After the rake reaches the deceleration limit, the deceleration limit is triggered, and the PLC receives the signal from the deceleration limit, controlling the rake to decelerate via the frequency converter. Subsequently, the rake continues to move. Upon reaching the outrigger's permitted movement limit, the outrigger's permitted movement limit is triggered, and the PLC receives the signal from the outrigger's permitted movement limit. The rake extends its outriggers. Subsequently, the rake continues to move and enters a constant speed running phase. The rake reaches the forward positioning limit, the forward positioning limit is triggered, and the PLC receives the signal from the forward positioning limit, controlling the rake to stop. The electromagnet engages, ensuring the rake is secure and reliable.

[0063] While controlling the rake to move backward, a reversal coefficient is assigned to the frequency converter. The frequency converter is then started. The rake reaches the outrigger's permissible movement limit, which is triggered, and the PLC receives the signal from the outrigger's permissible movement limit. The rake retracts its outriggers. The rake continues to move. After the rake reaches the deceleration limit, it is triggered, and the PLC receives the signal from the deceleration limit, controlling the rake to decelerate via the frequency converter. Subsequently, the rake continues to move and enters a constant speed operation phase. The rake reaches the reverse end limit, which is triggered, and the PLC receives the signal from the reverse end limit, controlling the rake to stop.

[0064] The technical solution provided in this application, based on a control unit, frequency converter, asynchronous motor or synchronous motor, adopts a combination strategy of constant V / F control + multi-stage limit deceleration + electromagnet positioning, which can achieve low-cost, high-precision and high-safety position control of the rain rake.

[0065] The technical solution provided in this application can be applied to the fire extinguishing test bench of a civil aircraft. It is suitable for scenarios with high requirements for equipment cost, positioning accuracy and motion safety. It can also be applied to fixed-point motion control scenarios in industrial settings such as steel, metallurgy and non-ferrous metal processing.

[0066] The technical solution provided in this application can achieve the following beneficial effects: 1) Significantly reduced costs. Using asynchronous or synchronous motors and frequency converters, the overall cost can be reduced by 15%-20%. 2) Reliable control effect. It achieves precise position control of moving parts using asynchronous or synchronous motors combined with frequency converters, realizing accurate positioning and smooth start-stop, meeting usage requirements. 3) Strong system versatility. Using frequency converters and control units, maintenance is simple and spare parts are readily available. 4) High safety level. Multiple limit switches, deceleration, positioning and fixing, and STO safety protection ensure stable and risk-free operation, guaranteeing reliable and safe equipment operation. 5) Wide range of applications. It can be used in scenarios such as test benches, industrial transfer equipment, and fixed-point moving mechanisms.

[0067] The preferred embodiments of this application have been described in detail above. However, this application is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this application, various simple modifications can be made to the technical solution of this application, and these simple modifications all fall within the protection scope of this application.

[0068] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this application will not describe the various possible combinations separately.

[0069] Furthermore, various different implementations of this application can be combined in any way, as long as they do not violate the spirit of this application, they should also be regarded as the content disclosed in this application.

Claims

1. A control system for a moving component, characterized in that, The control system includes: A position determination unit is used to determine the position of the moving component; A drive unit for driving the moving component, wherein the drive unit includes a motor and a frequency converter, and the motor is an asynchronous motor or a synchronous motor; A control unit is used to control the moving component through the drive unit based on the position determined by the position determination unit.

2. The control system according to claim 1, characterized in that, The control system also includes: A fixing unit is used to fix the moving part after the moving part reaches a preset position.

3. The control system according to claim 2, characterized in that, The fixing unit is an electromagnet.

4. The control system according to claim 1, characterized in that, The location determination unit includes: The forward positioning limit is used to determine the position where the moving part needs to stop moving when it is moving towards the target; The deceleration limit switch is used to determine the position where the moving part needs to decelerate; The retraction limit switch is used to determine the position where the moving part needs to stop moving when it moves away from the target; The control unit is used for: Upon receiving the signal from the forward positioning limit or the backward positioning limit, the driving unit controls the moving component to stop moving; Upon receiving the deceleration limit signal, the driving unit controls the moving component to decelerate.

5. The control system according to claim 4, characterized in that, The location determination unit further includes: The forward limit stop is used to determine the maximum position that the moving part can reach when moving towards the target; The backward limit stop is used to determine the extreme position that the moving part can retreat to when it is far away from the target; The control unit is further configured to: Upon receiving the signal from the forward limit switch or the backward limit switch, the driving unit controls the moving component to stop moving.

6. The control system according to claim 4, characterized in that, The movable component is a rain rake, and the position determination unit further includes: The outrigger allows for movement limits, used to determine the position of the outrigger when it is extended or retracted; The control unit is further configured to: When the outrigger is received as the rake moves forward, the outrigger is extended by the drive unit. If a signal indicating that the outriggers are allowed to move is received during the retraction of the rake, the drive unit controls the rake to retract its outriggers.

7. The control system according to claim 1, characterized in that, The control unit is also used for: Upon receiving a forward command, the frequency converter controls the motor to rotate forward; Upon receiving a reverse command, the frequency converter controls the motor to reverse.

8. The control system according to claim 7, characterized in that, The moving component is a rain rake, and the control system also includes: The door opening determination unit is used to determine whether the front door of the fire extinguishing test bench is open; The control unit is further configured to: upon receiving a forward command, if the door opening determination unit determines that the forward gate of the fire extinguishing test bench is open, then control the rain rake to move toward the fire extinguishing test bench.

9. The control system according to claim 1, characterized in that, The control system also includes: The STO safety circuit is used to issue an emergency stop signal. The control unit is further configured to: control the moving part to stop suddenly upon receiving an emergency stop signal from the STO safety circuit.

10. The control system according to claim 1, characterized in that, The control unit is also used for: In the event of motor overload, overcurrent, or overheating, the motor shall be controlled to stop immediately.

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