Piston electromagnetic actuator and control method thereof

Abstract

The application discloses a piston electromagnetic driver and a control method thereof, and comprises the following steps: step S0 initial locking: electromagnetic attraction maintains the piston at a first limit position; step S1 full stroke reference calibration: the electromagnetic coil is powered off, and the piston is reset to a second limit position under the action of a reset spring; step S2 initial parameter assignment: taking the complete reset time Tmax as an initial power-off time T0; setting a preset stroke L(s) and a unit adjustment time t; step S3 step-by-step gradual adjustment: setting an adjustment step number i, the electromagnetic coil is operated according to the power-off time T(i)=T0-i·t, and the corresponding actual stroke L(i) of the piston is collected; after single adjustment, i=i+1; step S4 stroke matching determination: comparing L(i) and L(s), if L(i)>L(s), repeating step S3; if L(i)≤L(s), stopping adjustment and locking the current i and i-1; and step S5 target time length fitting: fitting the target power-off time T(s) corresponding to the preset stroke L(s). The application can realize the adjustment of the piston pumping stroke.

Description

Technical Field

[0001] This invention relates to electromagnetic actuators, and more specifically, to a control method for a piston-type electromagnetic actuator, and also to a piston-type electromagnetic actuator controlled by the method. Background Technology

[0002] Existing piston-type electromagnetic drive devices mostly use an electromagnetic coil to engage when energized and a spring to reset when de-energized to achieve drive control. However, current electromagnetic drive solutions can only form a simple on / off control mode, which can only switch the piston between the full engagement limit position and the full reset limit position, and cannot adjust the pumping stroke of the piston. During the pumping process, only full-stroke control can usually be achieved, that is, the amount of liquid driven cannot be regulated.

[0003] Therefore, a new technical solution is needed to achieve single-pump liquid volume adjustment of the piston-type electromagnetic actuator. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a piston-type electromagnetic actuator and its control method.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A control method for a piston-type electromagnetic actuator includes the following steps:

[0007] Step S0 Initial Locking: The electromagnetic coil is continuously energized, and the electromagnetic attraction keeps the piston in the first extreme position;

[0008] Step S1 Full stroke reference calibration: The electromagnetic coil is de-energized, and the piston is reset to the second limit position under the action of the reset spring. The full stroke L0 of the piston and the time Tmax for complete reset are obtained.

[0009] Step S2 Initial parameter assignment: Take the complete reset time Tmax as the initial power-off time T0; Set the preset stroke L(s) and unit adjustment time t;

[0010] Step S3: Gradual adjustment: Set the adjustment level i, with an initial value of 1. The electromagnetic coil operates according to the power-off duration T(i) = T0 - i·t. After the duration is reached, the coil is immediately powered on, and the actual piston stroke L(i) is collected. After a single adjustment, i = i + 1.

[0011] Step S4: Stroke matching determination: Compare L(i) and L(s). If L(i) > L(s), repeat step S3; if L(i) ≤ L(s), stop the adjustment and lock the current i and i-1.

[0012] Step S5: Target duration fitting: Fit the target power-off time T(s) corresponding to the preset stroke L(s), satisfying T(i)≤T(s). <T(i-1)。

[0013] The present invention further includes the following steps:

[0014] Step S6: Difference Mean Compensation: Based on the time difference weight between T(i) and T(i-1), allocate the number of runs for T(i) and T(i-1) according to the weight, so that the average stroke of the multi-round pumping reaches the preset stroke L(s).

[0015] The present invention further states that, in step S6, the step of weighting the time difference is as follows:

[0016] Step S61: Calculate the single-wheel travel deviation:

[0017] The travel deviation at this level is: ΔL(i) = L(s) - L(i);

[0018] Previous travel deviation: ΔL(i-1) = L(i-1) - L(s);

[0019] Step S62: Calculate the travel weighting coefficient.

[0020] Weight coefficient for this level: α = ΔL(i-1) ÷ [ΔL(i) + ΔL(i-1)];

[0021] The weighting coefficient of the previous level is: β = ΔL(i) ÷ [ΔL(i) + ΔL(i-1)];

[0022] α is the operating weight for power outage duration T(i), β is the operating weight for power outage duration T(i-1), and α+β=1;

[0023] The ratio of the number of runs in step S63:

[0024] The weighting coefficients α and β are converted into the smallest integer number of alternating operation cycles.

[0025] The present invention further includes: in step S63, the number of runs is matched, T(i) runs N times and T(i-1) runs M times within a complete compensation cycle, N:M=α:β; and the number of runs of T(i) and T(i-1) is uniformly interleaved and alternated in a timing sequence.

[0026] The present invention further includes the following steps:

[0027] Step S7: Historical array storage: Record the corresponding historical data arrays of T(i) and L(i);

[0028] Step S8 Historical Array Recall: When resetting the set stroke L(s') in the future, if the set stroke L(s') is in the historical data array, it will be called directly; if not, step S3 gradual adjustment will be re-executed, and the historical data array will be updated and compensated.

[0029] The present invention further includes the following steps:

[0030] Step S9: Real-time dynamic correction

[0031] After locking the target power outage time T(s) and entering steady-state average pumping, the system enters the real-time dynamic monitoring and correction stage to continuously offset the deviation caused by dynamic changes in operating conditions.

[0032] The present invention further states that in step S9, a unified deviation calculation and judgment are performed over a complete compensation cycle, and a travel mean allowable deviation threshold ΔL (threshold) is preset in advance.

[0033] After a complete compensation cycle, the displacement detection unit collects all the actual stroke data of the pistons during the cycle and calculates the actual average stroke L (actual average) for the cycle.

[0034] Calculate the average deviation of the cycle: ΔL(weekly average) = L(s) - L(actual average), which is the difference between the preset target travel and the actual average travel of the cycle.

[0035] The present invention further states that: the difference between ΔL (weekly average) and ΔL (threshold) is compared; if |ΔL (weekly average)| ≤ ΔL (threshold), then the system enters a steady-state continuous operation mode.

[0036] If |ΔL(weekly average)|>ΔL(threshold), then dynamic correction adjustment is performed;

[0037] The steps for dynamic correction and adjustment are as follows: Determination of deviation direction: If ΔL (weekly average) > 0, it means that the average stroke of the cycle is too small, and the power outage time needs to be extended to make up for the stroke; if ΔL (weekly average) < 0, it means that the average stroke of the cycle is too large, and the power outage time needs to be shortened to reduce the stroke.

[0038] Small-scale adjustment of power outage duration: Based on the current two-level power outage durations T(i) and T(i-1), make small-scale adjustments in the same direction according to the unit adjustment time t to generate new adjusted durations T(i)' and T(i-1)'. The adjustment range shall not exceed 2 units of adjustment time to avoid overshoot caused by large adjustments.

[0039] Recalculate the weighting ratio: Collect the actual trips L(i)' and L(i-1)' corresponding to the adjusted duration, and recalculate the weighting coefficient and the ratio of alternating runs;

[0040] New cycle verification of correction effect: Execute the next complete compensation cycle according to the new duration and ratio, recalculate the cycle average travel and deviation value until the deviation falls back to within the allowable threshold.

[0041] This invention also provides a piston-type electromagnetic actuator, including a valve body 4 and a piston 5. The piston 5 is slidably mounted within the valve body 4, dividing the inner cavity of the valve body 4 into an inlet chamber 41 and an outlet chamber 42. The piston 5 is equipped with a second check valve 51, which allows unidirectional flow from the inlet chamber 41 to the outlet chamber 42. The inlet chamber 41 is connected to an inlet channel 31, and a first check valve 311 is installed in the inlet channel 31, allowing unidirectional flow to the inlet chamber 41. The outlet chamber 42 is connected to an outlet channel 32. The actuator also includes a return spring 6 and an electromagnetic drive mechanism. The electromagnetic drive mechanism magnetically drives the piston 5 to move toward a first position and maintains it at the first position. The return spring 6 elastically acts on the piston 5 away from the first position. A displacement sensor is also included to detect the displacement stroke of the piston 5. The actuator is controlled using the control method described above.

[0042] The present invention further states that the piston 5 reciprocates to pump the liquid in one direction, with the pumping direction from the inlet channel 31 to the outlet channel 32; during the pumping process, the pumped liquid also serves as the damping fluid for the piston 5.

[0043] In summary, the present invention has the following beneficial effects:

[0044] In this solution, by controlling the on and off time of the electromagnetic mechanism, the piston stroke can be regulated. It also breaks through the limitation of the traditional electromagnetic drive device, which can only realize the two-polarized switch control of the piston throughout the entire stroke and the piston throughout the entire stroke. Without making major changes to the existing drive structure, the piston stroke can be precisely and steplessly adjusted by optimizing the on and off time sequence at the software level. It can adapt to the different stroke and pumping volume requirements under different working conditions and has a wider range of applicable scenarios.

[0045] By introducing a difference mean compensation mechanism, the problem of not being able to accurately match the preset stroke through a single level of power outage duration is addressed. By using a two-level power outage duration weighting ratio and uniformly interleaved operation, the average stroke within multiple pumping cycles is made to perfectly match the preset target without any accumulated deviation. Even if there are slight fluctuations in the stroke of a single cycle, the pumping volume within the overall cycle remains constant, balancing control flexibility and operational stability, and eliminating the impact of local stroke fluctuations on the overall pumping accuracy. Attached Figure Description

[0046] Figure 1 This is a flowchart illustrating a control method for a piston-type electromagnetic actuator according to this embodiment.

[0047] Figure 2This is a schematic diagram of the piston-type electromagnetic actuator in this embodiment;

[0048] Figure reference numerals: 1. Electromagnetic coil; 2. Electromagnetic moving iron; 3. Valve stem; 31. Liquid inlet channel; 311. Check valve one; 32. Liquid outlet channel; 33. Stop block; 4. Valve body; 41. Liquid inlet chamber; 42. Liquid outlet chamber; 5. Piston; 51. Check valve two; 6. Return spring. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] This embodiment discloses a control method for a piston-type electromagnetic actuator, wherein the piston-type electromagnetic actuator is driven by an electromagnetic coil and, in conjunction with a one-way valve structure, can achieve one-way pumping.

[0051] The control method in this embodiment is adapted for use with a piston-type electromagnetic actuator, realizing the integration of the pumping medium and the damping fluid. Specifically, refer to... Figure 2 As shown, the piston-type electromagnetic actuator includes a valve body 4 and a piston 5. The piston 5 is slidably mounted inside the valve body 4, dividing the inner cavity of the valve body 4 into an inlet chamber 41 and an outlet chamber 42. The piston 5 is equipped with a second check valve 51, which allows unidirectional flow from the inlet chamber 41 to the outlet chamber 42. The inlet chamber 41 is connected to an inlet channel 31, and a first check valve 311 is installed in the inlet channel 31, allowing unidirectional flow to the inlet chamber 41. The outlet chamber 42 is connected to an outlet channel 32, forming a complete unidirectional pumping flow channel.

[0052] A valve stem 3 is inserted through the valve body 4, forming a sliding seal at the point where the valve stem 3 penetrates the valve body 4. A piston 5 is fixedly connected to the valve stem 3, and corresponding inlet and outlet channels 31 and 32 are located on the valve stem 3. An electromagnet 2 is also fixedly mounted on the valve stem 3, capable of being attracted to the electromagnet coil 1. A return spring 6 is supported by a stop 33 fixed externally to the valve stem 3, elastically pressing against the stop 33 and the housing to achieve elastic reset.

[0053] The piston-type electromagnetic actuator also includes a return spring 6 and an electromagnetic drive mechanism. The electromagnetic drive mechanism adopts an electromagnetic drive form, which generates electromagnetic attraction when energized, drives the piston to move toward the first extreme position, and keeps the piston locked in that position. The return spring is elastically installed in the valve body and can apply an elastic return force to the piston away from the first extreme position. When the power is off, it pushes the piston to reset to the second extreme position.

[0054] The piston-type electromagnetic actuator also includes a displacement sensor, which is correspondingly positioned to the piston. This sensor can accurately detect the piston's displacement stroke in real time and transmit the displacement signal to the main control unit, providing data support for stroke adjustment, compensation, and correction. During pumping, the pumped liquid simultaneously acts as the piston's damping fluid, eliminating the need for a separate damping structure. It utilizes the medium's own damping to achieve smooth resetting, conforming to dynamic damping fluctuation characteristics.

[0055] During the forward movement of piston 5, that is, when it moves to the first extreme position under the magnetic action of the electromagnetic actuator, the one-way valve 51 at piston 5 is closed, which can push the liquid to flow out of the inlet channel 31. During the reverse movement of piston 5, that is, when it moves to the second extreme position under the elastic action of the return spring, the one-way valve 51 at piston 5 will be slightly opened, and the liquid will slowly flow through the open orifice of the one-way valve 51, forming a slow damped movement. At the same time, the liquid in the inlet chamber 41 will be transferred to the outlet chamber 42.

[0056] The piston-type electromagnetic actuator in this embodiment is controlled in conjunction with the control method described in this embodiment. The reciprocating motion of the piston 5 pumps the liquid in one direction from the inlet channel 31 to the outlet channel 32; during the pumping process, the pumped liquid also acts as the damping fluid for the piston 5.

[0057] The control method in this embodiment adopts a step-by-step progressive logic, which is designed to achieve the target piston stroke average value throughout the process. Specifically, it is implemented by the following steps: initial lock-up, benchmark calibration, gradual adjustment, target fitting, mean compensation, historical data retrieval, and dynamic correction.

[0058] The relevant concepts involved in the control method of this embodiment are explained below:

[0059] First extreme position: The extreme position where piston 5 is attracted and locked under the attraction force of the electromagnetic coil is the end point of piston 5's attraction stroke;

[0060] Second extreme position: The extreme position where piston 5 is fully reset without interference under the elastic force of return spring 6, which is the end point of piston 5's reset stroke.

[0061] Piston full stroke L0: A mechanical fixed parameter, referring to the maximum linear sliding distance of piston 5 from the first limit position to the second limit position, which is determined by the structural dimensions of the actuator valve body 4 and is a fixed value.

[0062] Complete reset time Tmax: a benchmark calibration parameter, refers to the total time it takes for piston 5 to fully reset from the first limit position to the second limit position without intervention under standard operating conditions, which varies dynamically with temperature, medium viscosity, and component wear.

[0063] Initial power-off time T0: Progressive adjustment reference parameter, assigned as the time Tmax for complete reset, i.e., T0 = Tmax, which is the initial duration for step-by-step adjustment;

[0064] Adjustment level i: Progressive adjustment variable, with an initial value of 1. After each level of adjustment, i = i + 1, used to distinguish different power-off durations and corresponding piston strokes;

[0065] Unit adjustment time t: Fixed small adjustment step, which is the unit amplitude for gradually shortening the power-off duration. It can be flexibly set according to the pumping accuracy requirements to avoid overshoot caused by too large adjustment amplitude;

[0066] Graded power-off duration T(i): Core controllable parameter, with the calculation formula T(i) = T0 - i·t. It gradually decreases as the adjustment level increases and directly determines the actual reset stroke of piston 5;

[0067] Actual piston stroke L(i): Follow-up output parameter, which is the actual sliding distance of piston 5 corresponding to the graded power-off duration T(i), showing a non-linear correspondence with the power-off duration;

[0068] Preset stroke L(s): Target control parameter, which is the target reset stroke of piston 5 set by the user and is the core reference for full-course adjustment and correction;

[0069] Target power-off time T(s): Fitting and matching parameter, which precisely corresponds to the preset stroke L(s) and satisfies the interval relationship T(i) ≤ T(s) < T(i - 1), representing the power-off duration corresponding to the target reset stroke of piston 5;

[0070] Stroke deviation of this level ΔL(i): Mean compensation parameter, with the calculation formula ΔL(i) = L(s) - L(i), representing the under-quantity deviation of the piston 5 stroke from the preset stroke under the power-off duration of this level;

[0071] Stroke deviation of the previous level ΔL(i - 1): Mean compensation parameter, with the calculation formula ΔL(i - 1) = L(i - 1) - L(s), representing the over-quantity deviation of the piston 5 stroke from the preset stroke under the power-off duration of the previous level;

[0072] Weight coefficients α, β: Mean compensation ratio parameters, α is the operation weight of T(i), β is the operation weight of T(i - 1), α + β = 1, calculated from the ratio of piston 5 stroke deviations;

[0073] Complete compensation cycle: Mean compensation and correction unit, referring to the alternating operation cycle of T(i) running N times and T(i - 1) running M times, N:M = α:β. During the cycle, the average stroke of piston 5 fits the preset value;

[0074] Threshold of allowable deviation of stroke mean value ΔL(threshold): Dynamic correction determination parameter, presetting the allowable range of cycle average stroke deviation, which is a fixed value;

[0075] Actual average stroke L (actual average): A dynamically corrected calculation parameter, representing the arithmetic mean of the actual stroke of piston 5 within a single complete compensation cycle;

[0076] Cycle mean deviation ΔL (weekly average): A core parameter for dynamic correction. The calculation formula is ΔL (weekly average) = L(s) - L (actual average), which characterizes the overall deviation between the average stroke of piston 5 and the preset stroke within a cycle.

[0077] Reference Figure 1 As shown, the control method in this embodiment includes the following specific steps:

[0078] Step S0 Initial Locking: The control electromagnetic coil is continuously energized, and the electromagnetic attraction overcomes the spring force of the reset spring 6, keeping the piston 5 stably in the first limit position. The piston 5 has no reset movement, and the liquid inlet and liquid outlet processes corresponding to the liquid inlet channel 31 and the liquid outlet channel 32 are suspended, waiting for control commands, in order to prepare for the subsequent adjustment of the piston 5 stroke.

[0079] Step S1 Full stroke reference calibration: The electromagnetic coil is de-energized, and the piston is reset to the second limit position under the action of the reset spring. The full stroke L0 of the piston and the time Tmax for complete reset are obtained.

[0080] Step S2 Initial parameter assignment: After receiving the adjustment command, the electromagnetic coil is completely de-energized, the electromagnetic attraction disappears, and the piston 5, under the elastic force of the return spring 6, resets from the first limit position to the second limit position without intervention or premature termination of power-on; through the displacement sensor and timing unit, the full stroke L0 of the piston 5 and the complete reset time Tmax are collected synchronously to complete the calibration of the system reference parameters and provide a reference basis for the subsequent adjustment of the piston 5 stroke; set the preset stroke L(s) and unit adjustment time t;

[0081] Step S3: Gradual adjustment: Set the adjustment level i, with an initial value i=1; the main controller controls the electromagnetic coil to run according to the current level power-off duration T(i)=T0-i·t. After reaching the set power-off duration, immediately control the electromagnetic coil to re-energize, terminating the piston 5's reset movement, and the piston 5 retracts to the first limit position; the displacement sensor accurately collects the actual stroke L(i) of the piston 5 corresponding to this power-off duration; after a single adjustment is completed, update the adjustment level i=i+1, preparing for the next level of adjustment;

[0082] Step S4: Stroke Matching Determination: The main control unit compares the actual stroke L(i) of piston 5 with the preset stroke L(s) in real time, and performs the corresponding operation based on the comparison result:

[0083] If L(i)>L(s), it means that the current power outage duration is too long and the actual stroke of piston 5 exceeds the preset target. The power outage duration needs to be shortened further, and step S3 is repeated to carry out the next level of cycle adjustment.

[0084] If L(i) ≤ L(s), it indicates that the current power-off duration has approached the preset stroke requirement. Stop the step-by-step adjustment, lock the current adjustment level i and the previous adjustment level i - 1, and enter the target duration fitting link of the next step. Also, lock the current i and i - 1.

[0085] Step S5 Target duration fitting: After stopping the step-by-step adjustment, lock two key power-off durations, namely the current power-off duration T(i) and the previous power-off duration T(i - 1).

[0086] Fit to obtain the target power-off time T(s) that precisely corresponds to the preset stroke L(s) of the piston 5, satisfying the interval relationship T(i) ≤ T(s) < T(i - 1), complete the precise matching of the power-off duration and the preset stroke of the piston 5, and obtain the required target power-off time T(s).

[0087] During the control process, using the target power-off time T(s) as a reference, control the power-off time of the piston electromagnetic driver, and then be able to control and adjust the actual stroke amount of the piston stroke. Moreover, it can be controlled according to the required pumping volume, and the liquid volume pumped each time can be controlled.

[0088] Furthermore, according to the current power-off duration T(i) and the previous power-off duration T(i - 1), control the actual time. The specific steps of the control method in this embodiment further include:

[0089] Step S6 Difference mean compensation: Since the target power-off time T(s) is an interval fitting value, running alone with T(i) or T(i - 1) cannot make the single stroke of the piston 5 equal to the preset stroke L(s). Therefore, according to the time difference weight of T(i) and T(i - 1), distribute the running times of T(i) and T(i - 1) according to the weight situation, so that the average stroke of multiple rounds of pumping reaches the preset stroke L(s). The specific sub-steps are as follows:

[0090] S61 Calculate the single-round stroke deviation: Calculate the piston 5 stroke deviations corresponding to the two power-off durations respectively: The current-level stroke deviation ΔL(i) = L(s) - L(i); The previous-level stroke deviation ΔL(i - 1) = L(i - 1) - L(s);

[0091] S62 Calculate the stroke weight coefficient: Based on the piston 5 stroke deviation ratio, calculate the operating weight coefficient of the two-stage power outage duration. The core is to achieve the mean value target through deviation complementarity: the current stage weight coefficient α=ΔL(i-1)÷[ΔL(i)+ΔL(i-1)]; the previous stage weight coefficient β=ΔL(i)÷[ΔL(i)+ΔL(i-1)]; where α is the operating weight of the power outage duration T(i), β is the operating weight of the power outage duration T(i-1), and α+β=1. The larger the piston 5 stroke deviation of a certain stage, the higher the operating weight of the corresponding complementary stage.

[0092] S63 Running frequency ratio and alternation timing: The weight coefficients α and β in decimal form are converted into the smallest integer alternation running cycle. Within a complete compensation cycle, T(i) runs N times and T(i-1) runs M times, satisfying the ratio N:M=α:β. In order to facilitate the fitting, the ratios of N:M and α:β can also be approximately close, and a matching degree of more than 95% is sufficient to meet the requirements.

[0093] In addition, to avoid excessive fluctuations in the stroke of piston 5 in certain areas, the running sequence adopts a uniform interleaving and alternating mode, which evenly distributes the running times with small weights into the running processes with large weights, rather than running them in a concentrated and continuous manner, thus ensuring that the average stroke of piston 5 is stable within the cycle.

[0094] Furthermore, the control method in this embodiment further includes the following specific steps:

[0095] Step S7 Historical Array Storage: The main control unit has a built-in non-volatile storage module. During the entire process of gradual adjustment and mean compensation, it records and stores a historical data array that corresponds one-to-one with the power outage duration T(i) and the actual stroke L(i) of piston 5 in real time. The array includes the power outage duration, the corresponding piston 5 stroke, and operating parameters. The data is not lost after power failure, forming a historical database.

[0096] Step S8 Historical Array Retrieval: In subsequent operations, if a new preset stroke L(s') of piston 5 is reset, the main control unit will prioritize retrieving the historical data array. If the new preset stroke L(s') matches the actual stroke already stored in the array, the corresponding power-off duration and weight ratio parameters will be directly retrieved, eliminating the need to repeatedly perform step-by-step adjustments and significantly improving adjustment efficiency.

[0097] If the new preset stroke L(s') is not in the historical data array, repeat the step-by-step adjustment process of steps S3-S5, and add the new duration and piston stroke data to the historical array to continuously improve the database.

[0098] Furthermore, the control method in this embodiment further includes the following specific steps:

[0099] Step S9: Real-time dynamic correction

[0100] After locking the target power outage time T(s), completing the weighting ratio, and entering steady-state average pumping, the system enters the real-time dynamic monitoring and correction phase. Using the complete compensation cycle as the unified calculation and correction unit, it eliminates the instantaneous interference of a single piston stroke correction, continuously offsetting piston stroke deviations caused by dynamic changes in operating conditions such as temperature, viscosity, and wear. The specific sub-steps are as follows:

[0101] S91 Correction threshold and cycle setting: Pre-set the allowable deviation threshold ΔL (threshold) of the average travel value as the criterion for determining whether the deviation is qualified; take the complete compensation cycle determined in step S63 as the smallest correction unit, and carry out a deviation calculation and judgment once after each complete cycle, without performing sporadic correction for a single travel.

[0102] S92 Cycle Data Acquisition and Mean Calculation: After a single complete compensation cycle, the displacement sensor collects all the actual stroke data of piston 5 in this cycle. After removing extreme abnormal interference data, the actual average stroke L (actual average) of piston 5 in this cycle is calculated. Then, the cycle mean deviation value ΔL (cycle average) = L(s) - L (actual average) is calculated to accurately reflect the overall stroke deviation of piston 5 in the entire cycle.

[0103] S93 Deviation Judgment and Grading Processing: Compare the absolute value of the periodic mean deviation |ΔL(weekly average)| with the preset threshold ΔL(threshold), and perform the corresponding operation based on the comparison result:

[0104] Case 1: Deviation is acceptable. If |ΔL(weekly average)|≤ΔL(threshold), it is determined that the current power outage duration and weight ratio are suitable for the current working condition. It directly enters the steady-state continuous operation mode, keeps the existing parameters and alternation sequence unchanged, automatically enters the next complete compensation cycle, and continuously cycles without performing correction operations. The piston stroke 5 remains stable.

[0105] Scenario 2: Deviation exceeds the limit. If |ΔL(weekly average)|>ΔL(threshold), it is determined that the operating condition has fluctuated and the original parameters are no longer suitable. Dynamic correction adjustment is initiated to accurately correct the piston stroke 5. The specific correction steps are as follows:

[0106] 1. Determination of deviation direction: If ΔL (average per cycle) > 0, it means that the average stroke of piston 5 within the cycle is too small, and the power-off time needs to be slightly extended to supplement the stroke of piston 5; if ΔL (average per cycle) < 0, it means that the average stroke of piston 5 within the cycle is too large, and the power-off time needs to be slightly shortened to reduce the stroke of piston 5.

[0107] 2. Fine-tuning the power outage duration: Based on the current two-stage power outage durations T(i) and T(i-1), make small adjustments in the same direction according to the unit adjustment time t to generate new fine-tuned durations T(i)' and T(i-1)'. The fine-tuning range is strictly controlled within 2 units of adjustment time to avoid large adjustments that could lead to overshoot.

[0108] 3. Recalculate the weight ratio: Collect the actual stroke L(i)' and L(i-1)' of piston 5 corresponding to the power-off time after fine adjustment by the displacement sensor, and recalculate the weight coefficient and the ratio of alternating operation times according to the piston 5 stroke difference weight formula in step S62.

[0109] 4. Verify the effect of the correction in the new cycle: According to the new power outage duration and operating ratio, execute the next complete compensation cycle, recalculate the piston's 5-cycle average stroke and deviation value, and repeat the above fine-tuning and calculation steps until the deviation falls back to within the allowable threshold.

[0110] S94 data update after correction: After dynamic correction is completed and deviation is within acceptable limits, the new power outage duration, the corresponding actual stroke of piston 5, and the latest weight ratio are updated to the historical data array simultaneously, overwriting the original old working condition data, retaining the effective parameters that are suitable for the current working condition, and ensuring the accuracy of subsequent historical calls and corrections.

[0111] If deviations exceed the limit for three consecutive complete compensation cycles, a rapid and gradual readjustment is automatically triggered to quickly adapt to large fluctuations in operating conditions and ensure the long-term operating accuracy of piston 5.

[0112] After completing gradual adjustment, mean compensation, and dynamic correction, the system locks the optimal control parameters and enters a long-term steady-state operation mode. During operation, the main control unit continuously monitors the piston stroke deviation on a periodic basis, refreshes historical data periodically, removes invalid and outdated data, and retains the most recent valid data. No manual intervention is required throughout the process, achieving adaptive, high-precision, and long-term steady-state piston stroke and quantitative pumping control.

[0113] This embodiment of a piston-type electromagnetic actuator employs the aforementioned control method. The actuator exhibits rapid pumping response, piston 5 operates without rigid impact, piston 5 stroke control deviation is stably controlled within the required precision stroke, mean value compensation eliminates deviation accumulation, and dynamic correction response is timely, fully meeting the requirements for precise quantitative pumping. Furthermore, in this embodiment, the pumped liquid can simultaneously act as a damping fluid. Through dynamic correction, the damping effect caused by factors such as temperature, concentration, and viscosity of the pumped liquid can be avoided. The correction method of this embodiment enables precise control and compensation adjustment.

[0114] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A control method for a piston-type electromagnetic actuator, characterized in that, Including the following steps: Step S0 Initial Locking: The electromagnetic coil is continuously energized, and the electromagnetic attraction keeps the piston in the first extreme position; Step S1 Full stroke reference calibration: The electromagnetic coil is de-energized, and the piston is reset to the second limit position under the action of the reset spring. The full stroke L0 of the piston and the time Tmax for complete reset are obtained. Step S2 Initial parameter assignment: Take the complete reset time Tmax as the initial power-off time T0; Set the preset stroke L(s) and unit adjustment time t; Step S3: Gradual adjustment: Set the adjustment level i, with an initial value of 1. The electromagnetic coil operates according to the power-off duration T(i) = T0 - i·t. After the duration is reached, the coil is immediately powered on, and the actual piston stroke L(i) is collected. After a single adjustment, i = i + 1. Step S4: Stroke matching determination: Compare L(i) and L(s). If L(i) > L(s), repeat step S3; if L(i) ≤ L(s), stop the adjustment and lock the current i and i-1. Step S5: Target duration fitting: Fit the target power-off time T(s) corresponding to the preset stroke L(s), satisfying T(i)≤T(s). <T(i-1)。 2. The control method for a piston-type electromagnetic actuator according to claim 1, characterized in that, It also includes the following steps: Step S6: Difference Mean Compensation: Based on the time difference weight between T(i) and T(i-1), allocate the number of runs for T(i) and T(i-1) according to the weight, so that the average stroke of the multi-round pumping reaches the preset stroke L(s).

3. The control method for a piston-type electromagnetic actuator according to claim 2, characterized in that, In step S6, the steps for weighting the time difference are as follows: Step S61: Calculate the single-wheel travel deviation: The travel deviation at this level is: ΔL(i) = L(s) - L(i); Previous travel deviation: ΔL(i-1) = L(i-1) - L(s); Step S62: Calculate the travel weighting coefficient. Weight coefficient for this level: α = ΔL(i-1) ÷ [ΔL(i) + ΔL(i-1)]; The weighting coefficient of the previous level is: β = ΔL(i) ÷ [ΔL(i) + ΔL(i-1)]; α is the operating weight for power outage duration T(i), β is the operating weight for power outage duration T(i-1), and α+β=1; The ratio of the number of runs in step S63: The weighting coefficients α and β are converted into the smallest integer number of alternating operation cycles.

4. The control method for a piston-type electromagnetic actuator according to claim 3, characterized in that, In step S63, the number of runs is matched. Within a complete compensation cycle, T(i) runs N times and T(i-1) runs M times, N:M=α:β; and the number of runs of T(i) and T(i-1) is uniformly interleaved and alternated in time.

5. The control method for a piston-type electromagnetic actuator according to claim 1, characterized in that, It also includes the following steps: Step S7: Historical array storage: Record the corresponding historical data arrays of T(i) and L(i); Step S8: Historical array call: If the set process L(s') is in the historical data array, then call it directly when resetting the process L(s') in the future. If not, repeat step S3 for gradual adjustment and update and compensate the historical data array.

6. The control method for a piston-type electromagnetic actuator according to claim 1, characterized in that, It also includes the following steps: Step S9: Real-time dynamic correction After locking the target power outage time T(s) and entering steady-state average pumping, the system enters the real-time dynamic monitoring and correction stage to continuously offset the deviation caused by dynamic changes in operating conditions.

7. The control method for a piston-type electromagnetic actuator according to claim 6, characterized in that, In step S9, a unified deviation calculation and judgment are performed over a complete compensation cycle, and the allowable deviation threshold ΔL (threshold) of the average travel value is preset in advance. After a complete compensation cycle, the displacement detection unit collects all the actual stroke data of the pistons during the cycle and calculates the actual average stroke L (actual average) for the cycle. Calculate the average deviation of the cycle: ΔL(weekly average) = L(s) - L(actual average), which is the difference between the preset target travel and the actual average travel of the cycle.

8. The control method for a piston-type electromagnetic actuator according to claim 7, characterized in that, Compare the difference between ΔL (weekly average) and ΔL (threshold). If |ΔL (weekly average)| ≤ ΔL (threshold), then enter the steady-state continuous operation mode. If |ΔL(weekly average)|>ΔL(threshold), then dynamic correction adjustment is performed; The steps for dynamic correction and adjustment are as follows: Determination of deviation direction: If ΔL (weekly average) > 0, it means that the average stroke of the cycle is too small, and the power outage time needs to be extended to make up for the stroke; if ΔL (weekly average) < 0, it means that the average stroke of the cycle is too large, and the power outage time needs to be shortened to reduce the stroke.

9. A piston-type electromagnetic actuator, characterized in that, Includes a valve body (4) and a piston (5). The piston (5) is slidably installed inside the valve body (4) and divides the inner cavity of the valve body (4) into an inlet chamber (41) and an outlet chamber (42). The piston (5) is equipped with a second check valve (51), which is capable of unidirectional flow from the inlet chamber (41) to the outlet chamber (42). The inlet chamber (41) is connected to an inlet channel (31), which is equipped with a first check valve (311). The first check valve (311) is capable of... The inlet chamber (41) is unidirectionally connected; the outlet chamber (42) is connected to the outlet channel (32); it also includes a return spring (6) and an electromagnetic drive mechanism, the electromagnetic drive mechanism being used to magnetically drive the piston (5) to move toward the first position and be able to maintain it at the first position; the return spring (6) is able to elastically act on the piston (5) away from the first position; it also includes a displacement sensor for detecting the displacement stroke of the piston (5); and it is controlled by the control method described in any one of claims 1-8.

10. A piston-type electromagnetic actuator according to claim 9, characterized in that, The piston (5) reciprocates to pump the liquid in one direction from the inlet channel (31) to the outlet channel (32); during the pumping process, the pumped liquid also serves as the damping fluid for the piston (5).

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