Pressure regulating and alarming method for double-piston pump type medical water jet

Abstract

This invention discloses a pressure regulation and alarm method for a dual-piston pump type medical water jet, relating to the field of control technology, which can solve the problem of existing water jets having difficulty in automatic pressure regulation. The embodiments of this invention disclose a pressure regulation method for a dual-piston pump type medical water jet, including the following steps: adjusting the motor speed to a preset speed V0, obtaining the effective current value I of the motor; obtaining the target current I0 corresponding to the preset speed V0 based on several sets of relationships f(V, I); calculating the difference between the target current I0 and the effective current value I, and comparing it with a preset threshold; if the absolute value of the difference is less than the preset threshold, maintaining the motor speed; if the absolute value of the difference exceeds the preset threshold, and I is greater than I0, reducing the motor speed; if the absolute value of the difference exceeds the preset threshold, and I is less than I0, increasing the motor speed; using the changed motor speed as the new preset speed V0, repeating steps S1 to S3 until the difference between the target current I0 and the effective current value I is less than the preset threshold.

Description

Technical Field

[0001] This invention relates to the field of control technology, specifically to a method for pressure regulation and alarm of a dual-piston pump type medical water jet. Background Technology

[0002] A dual-piston pump medical water jet is a medical device that uses high-pressure water jets for precise cutting and tissue removal. Its working principle is based on accelerating ordinary water to extremely high speeds through a very fine nozzle, creating a "water jet" capable of precisely cutting soft tissue. The dual-piston pump compresses the water through alternating motion, significantly increasing its pressure. This alternating motion design ensures the continuity and stability of the water flow, reducing the impact of water pressure fluctuations on cutting accuracy.

[0003] As a medical water jet, the intensity of the external water jet must not be too high to ensure the safety of its medical applications. On the other hand, due to the structural strength limitations of the disposable medical sterile tubing, excessive water pressure inside the pump will lead to tubing damage, and liquid leakage will cause further hazards. Therefore, a fixed alternating motion speed is usually set to produce a specific water pressure output, that is, a specific intensity of the external water jet.

[0004] However, in practical applications, several factors affect the stability of water pressure output: First, due to differences in medical aseptic requirements and surgical procedures, different water jet tip sections need to be replaced, leading to inconsistencies in the water outlet micropores. Since the pistons use the same motion characteristics, pressure differences arise. Second, medical water jets use physiological saline, which can crystallize and precipitate solid particles, causing some outlet diameters to shrink or even become blocked, resulting in a rapid increase in water pressure. Third, during use, friction against the cutting tissue and the accumulation of contaminants from high-frequency electrosurgical treatments can also clog some outlets, causing rapid changes in water pressure. Fluctuations in water pressure from medical water jets can affect the surgeon's operation, and excessively high water pressure can lead to medical accidents and physical damage to weak points in the pipeline structure. Therefore, it is necessary to design a pressure regulation and alarm method for dual-piston pump medical water jets to address at least one of the above problems.

[0005] Therefore, this application is submitted. Summary of the Invention

[0006] The purpose of this application is to provide a pressure adjustment and alarm method for a dual-piston pump type medical water jet, solving the problems of existing medical water jets that are difficult to automatically adjust pressure and alarm according to actual conditions.

[0007] To address the above problems, this application provides the following technical solution:

[0008] On the one hand, this application provides a pressure adjustment method for a dual-piston pump type medical water jet, including the following steps:

[0009] S1. Adjust the motor speed to the preset speed V0 and obtain the effective current value I of the motor in real time;

[0010] S2. Based on the preset speed V0 of the motor and the relationship f(V, I) under several different target water jet pressures P0 obtained in advance, obtain the target current I0 corresponding to the preset speed V0.

[0011] The f(V, I) is: the mapping relationship between motor speed V and effective current value I under different blockage states of the water outlet when the water jet pressure is maintained at P0.

[0012] S3. Calculate the difference between the target current I0 and the effective current value I, and compare it with the preset threshold.

[0013] If the absolute value of the difference is less than the preset threshold, the motor speed V is kept at the preset speed V0.

[0014] If the absolute value of the difference is greater than the preset threshold and I is greater than I0, then reduce the motor speed.

[0015] If the absolute value of the difference is greater than the preset threshold and I is less than I0, then the motor speed is increased.

[0016] S4. Take the changed motor speed as the new preset speed V0, and repeat S1 to S3 until the absolute value of the difference between the target current I0 and the effective current value I is less than the preset threshold.

[0017] Optionally, in step S1, the effective current value I of the motor needs to be obtained based on the real-time current value of the motor and the position of the piston driven by the motor rotation. The method for obtaining this value is as follows:

[0018] The piston position is effectively sampled by a position acquisition sensor or an angle encoder set on the motor shaft. At the same time, the real-time current value of the motor is sampled. If the piston is in the stage of generating water pressure in the compression pump chamber from the starting position A to the ending position B, or if the real-time current value sampling data shows a continuous upward trend, it is determined that the motor is under load. At this time, the current corresponding to the stroke of the piston driven by the motor from point A to point B can be used as the effective current value I after feature extraction.

[0019] Optionally, the stroke of the piston driven by the motor from point A to point B is the middle 2 / 5 of the entire piston stroke when the motor is under load, thereby eliminating the impact of sudden current changes caused by motor start-stop.

[0020] Optionally, in S2 there is at least one set of relationships f(V, I) under the target water jet pressure P0 based on the product set pressure value.

[0021] Optionally, the relationship f(V, I) under the target water jet pressure P0 is obtained according to the following method:

[0022] S21. Install a water pressure sensor at the outlet of the medical water jet to measure the real-time water pressure value P, and adjust the motor speed to the preset speed V0.

[0023] S22. Adjust the preset speed V0 of the motor to several preset speeds V1 to Vn, change the degree of blockage at the outlet, until the real-time water pressure value P measured by the water pressure sensor is adjusted to the target water jet pressure P0 each time, record the effective current value when the motor speed is adjusted from V0 to V1 to Vn and the real-time water pressure value P is equal to the target water jet pressure P0.

[0024] S23. Establish a rectangular coordinate system with the motor speed on the horizontal axis and the effective current value on the vertical axis. Based on V1 to Vn in S22 and the coordinate points of several corresponding effective current values, draw the mapping curve of the relationship f(V, I).

[0025] The speed of the motor in the rectangular coordinate system is the motor rotation speed.

[0026] Optionally, when it is necessary to obtain the relationship f(V, I) under different target water jet pressures P0, the motor speed needs to be adjusted to the preset speed V0 first, and then the degree of blockage at the outlet is changed so that the water pressure value P measured by the water pressure sensor installed at the outlet is the target water jet pressure P0 for this time. Then, steps S22 and S23 are repeated.

[0027] Optionally, it also includes S5, recording the specific values ​​of the motor speed that changed in S4, and the difference between the target current I0 and the effective current value I;

[0028] If the speed decreases continuously for n times in the record, and the difference between the target current I0 and the effective current value I remains unchanged or increases, then the motor speed will be adjusted to the lowest preset speed V3, or the motor speed will be adjusted to 0, and an abnormal display signal will be output.

[0029] n is a preset integer.

[0030] On the other hand, this application provides an alarm method for a dual-piston pump type medical water jet, which is adapted to the pressure adjustment method of any of the dual-piston pump type medical water jets described above. In S2 of the pressure adjustment method, the target water jet pressure includes at least two types of alarm target water jet pressure and pressure adjustment target water jet pressure in the relationship f(V,I) under the target water jet pressure P0.

[0031] In step S1 of the pressure regulation method, after the motor speed is adjusted to V0, or after the motor speed is changed in step S3 of the pressure regulation method, it is necessary to obtain the alarm current Im based on the relationship f(V, I) set according to the alarm target water jet pressure and the adjusted motor speed. The effective value of the current I at the current speed is compared with the alarm current Im. If the effective value of the current I at the current speed is greater than or equal to the alarm current Im, an alarm display signal is output.

[0032] Optionally, the alarm target water jet pressure is a safety limit value for the product application, and the alarm target water jet pressure is higher than the pressure regulating target water jet pressure.

[0033] The beneficial effects of this invention are:

[0034] This application collects information on the motor's speed, current, and the position of the piston driven by the motor. Based on the pre-established target water jet pressure setting relationship f(V, I), it can reflect the mapping relationship between motor speed and current under the target water jet pressure. This allows the application to determine whether the current water jet pressure will deviate from the preset target water jet pressure value due to changes in the degree of blockage, based on the effective current value obtained from the current and position information, and the current speed value. Then, based on the determination result, the motor speed is directly adjusted so that the effective current value approaches the target current value. Thus, in actual use, this application can automatically adjust the water jet pressure to near the target water jet pressure value under different degrees of blockage without monitoring the actual degree of blockage at the water jet outlet. This ensures that the water jet pressure value is stable during the operation, thereby solving the problem of difficulty in adjusting the water jet pressure due to changes in outlet blockage. Attached Figure Description

[0035] Figure 1 This is a schematic diagram illustrating the relationship between piston position and current value, with motor running time as the horizontal axis and motor position and current value as the vertical axis, in an embodiment of this application.

[0036] Figure 2 This is a schematic diagram of the mapping curves corresponding to three sets of relationships f(V, I) when the target water jet pressure P0 is 2 MPa, 4 MPa, and 6 MPa, respectively, in an embodiment of this application.

[0037] Figure 3 This is a schematic diagram illustrating the relationship between the piston position and the current value when the motor is under load and the effective current value I is within the middle 2 / 5 of the entire active stroke, as described in this embodiment of the application.

[0038] Figure 4 This is a structural diagram of the system used in the embodiments of this application.

[0039] Figure 5 This is a schematic diagram of the pump body structure of the medical water jet dual piston pump in the embodiments of this application. Detailed Implementation

[0040] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0041] The medical water jet of this invention uses a dual-piston pump to provide water jet pressure. The mechanism of the dual-piston pump is as follows: the head and piston rod are integrated and are replaceable sterile disposable parts. Two motors drive two piston rods to perform push-pull reciprocating motion. The pump head has two one-way valve water paths in a single chamber. One path only allows water to be injected into the water jet head, and the other path only allows water to be drawn in from the outside. This allows the pump head to draw water from the outside when the piston rod is pulled and press water into the water jet head when it is pushed, forming a high-pressure water jet.

[0042] The two single chambers of the pump head work on the same principle, moving asynchronously at the same frequency to form a continuous and stable high-pressure water jet. Therefore, when adjusting the pressure of the water jet at the outlet of the water jet, the two single chambers of the dual piston pump can be controlled separately, and the control logic and method of the two single chambers are the same.

[0043] The following detailed description is provided with reference to the accompanying drawings.

[0044] Example 1:

[0045] like Figure 1 and Figure 2 As shown, this embodiment provides a pressure adjustment method for a dual-piston pump type medical water jet, including the following steps:

[0046] S1. Adjust the motor speed to the preset speed V0 and obtain the effective current value I of the motor in real time;

[0047] S2. Based on the preset speed V0 of the motor and the relationship f(V, I) under several different target water jet pressures P0 obtained in advance, obtain the target current I0 corresponding to the preset speed V0.

[0048] The f(V, I) is: the mapping relationship between motor speed V and effective current value I under different blockage states of the water outlet when the water jet pressure is maintained at P0; S3, calculate the difference between the target current I0 and the effective current value I, and compare it with the preset threshold.

[0049] If the absolute value of the difference is less than the preset threshold, the motor speed V is kept at the preset speed V0.

[0050] If the absolute value of the difference is greater than the preset threshold and I is greater than I0, then reduce the motor speed.

[0051] If the absolute value of the difference is greater than the preset threshold and I is less than I0, then the motor speed is increased.

[0052] S4. Take the changed motor speed as the new preset speed V0, and repeat S1 to S3 until the absolute value of the difference between the target current I0 and the effective current value I is less than the preset threshold. The specific value of the preset threshold can be set by the technician as needed, and will not be elaborated here.

[0053] In this embodiment, by collecting information on the motor's speed, current, and the position of the piston driven by the motor, and based on the pre-established target water jet pressure setting relationship f(V, I), the mapping relationship between motor speed and current under the target water jet pressure can be reflected. This embodiment can determine whether the current water jet pressure value will not conform to the preset target water jet pressure value due to changes in the degree of blockage, based on the effective current value obtained from the current and position information, and the current speed value. Then, based on the determination result, the motor speed is directly adjusted so that the effective current value approaches the target current value. Thus, in actual use, this embodiment can automatically adjust the water jet pressure to near the target water jet pressure value under different degrees of blockage without monitoring the actual degree of blockage at the water jet outlet, ensuring the stability of the water jet pressure value during the operation. This solves the current problem of difficulty in adjusting the water jet pressure due to changes in outlet blockage.

[0054] The concept of this embodiment is that, based on the calibrated target water jet pressure value P0 and the mapping relationship between the motor speed V and the effective current of the motor, the effective current value I and the motor speed V required to maintain the target water jet pressure value P0 under different blockage states are marked in advance. Therefore, in actual use, once a blockage occurs, the motor speed V can be adjusted successively according to the mismatched effective current value I and motor speed V, and the effective current value I after each motor speed adjustment can be monitored until the adjusted motor speed V and effective current value I meet the relationship f(V, I) under the target water jet pressure value P0. At this time, under the target water jet pressure P0, the blockage state corresponding to the current motor speed V and effective current value I matches the actual blockage state of the water jet outlet, and the actual water jet pressure P matches the target water jet pressure P0.

[0055] Taking a fixed water jet pressure of P1 = 2 MPa as an example, the relationship between the operating speed V of different motion motors and the effective current I is as follows: Figure 2As shown. When the water jet outlet Z is not heavily clogged, a higher motor operating speed V is required, and the corresponding effective current value I is also higher. A higher motor operating speed V can provide a larger flow rate to generate the corresponding water pressure. When the water jet outlet is heavily clogged, a lower motor operating speed V is required, and the corresponding effective current value I is also lower. A lower motor operating speed V can provide a smaller flow rate to generate the corresponding water pressure.

[0056] In this embodiment, in step S1, the effective current value I of the motor needs to be obtained based on the real-time current value of the motor and the position of the piston driven by the rotation of the motor. The method for obtaining this value is as follows:

[0057] The piston position is effectively sampled by a position acquisition sensor or an angle encoder set on the motor shaft. At the same time, the real-time current value of the motor is sampled. If the piston is in the stage of generating water pressure in the compression pump chamber from the starting position A to the ending position B, or if the real-time current value sampling data shows a continuous upward trend, it is determined that the motor is under load. At this time, the current corresponding to the stroke of the piston driven by the motor from point A to point B can be used as the effective current value I after feature extraction.

[0058] like Figure 1 As shown in the Cartesian coordinate system, the motor's position refers to the position of the piston driven by the motor. The piston's entire stroke is divided into 1000 segments. During the segment from position 1000 to 0, the piston pulls back, and the current is approximately 300mA. This current is the motor's dynamic current under no-load condition and does not require attention. During the segment from position 0 to 1000, the piston pushes forward, generating water pressure. The water pressure inside the pump acts as a load, thus increasing the current to 1500mA. This current is the effective current, directly reflecting the intensity of the water pressure inside the pump. Due to factors such as current signal interference and gradual changes in water pressure during piston movement, this embodiment uses the average current between points A and B driven by the motor as the effective current value I, making the change in effective current value correspond more accurately to the change in water pressure.

[0059] In this embodiment, the stroke of the piston driven by the motor from point A to point B is the middle 2 / 5 of the entire piston stroke when the motor is under load. This eliminates the impact of sudden current changes caused by motor start-stop. That is, the average current monitored during the piston stroke from 400 to 800 is the effective current value I. In some embodiments, the middle 1 / 2 or 3 / 5 of the entire piston stroke can also be used, which will not be elaborated here.

[0060] In this embodiment, as Figure 2As shown, in S2 there are three sets of relationships f(V,I) under water jet pressure P0 for different targets. The three sets of different target water jet pressure P0 are P1=2MPa, P2=4MPa, and P3=6MPa. 2MPa, 4MPa, and 6MPa are common water jet pressure values ​​in water jets. Technicians can also set specific values ​​as needed.

[0061] In this embodiment, the relationship f(V, I) under the target water jet pressure P0 is obtained according to the following method:

[0062] S21. Install a water pressure sensor at the outlet of the medical water jet to measure the real-time water pressure value P, and adjust the motor speed to the preset speed V0.

[0063] S22. Adjust the preset speed V0 of the motor to several preset speeds V1 to Vn, change the degree of blockage at the outlet, until the real-time water pressure value P measured by the water pressure sensor is adjusted to the target water jet pressure P0 each time, record the effective current value when the motor speed is adjusted from V0 to V1 to Vn and the real-time water pressure value P is equal to the target water jet pressure P0.

[0064] S23. Establish a rectangular coordinate system with the motor speed on the horizontal axis and the effective current value on the vertical axis. Based on V1 to Vn in S22 and the coordinate points of several corresponding effective current values, draw the mapping curve of the relationship f(V, I).

[0065] The speed of the motor in the rectangular coordinate system is the motor rotation speed.

[0066] In this embodiment, when it is necessary to obtain the relationship f(V, I) under different target water jet pressures P0, the motor speed needs to be adjusted to the preset speed V0 first, and then the degree of blockage of the outlet is changed so that the water pressure value P measured by the water pressure sensor installed at the outlet is the target water jet pressure P0 for this time. Then, steps S22 and S23 are repeated.

[0067] In some embodiments, the motor speed V can be determined, and after changing the degree of blockage at the outlet, the relationship f(P, I) at the target speed can be obtained. After obtaining multiple sets of relationships f(P, I) at different target speeds, several sets of relationships f(V, I) at different target water jet pressures P0 can be plotted based on multiple sets of relationships f(P, I) at different target speeds and with multiple sets of different target water jet pressures P0 as calibration.

[0068] In this embodiment, it also includes S5, recording the specific values ​​of the motor speed that changed in S4, as well as the difference between the target current I0 and the effective current value I;

[0069] If the speed decreases continuously for n times in the record, and the difference between the target current I0 and the effective current value I remains unchanged or increases, then the motor speed will be adjusted to the lowest preset speed V3, or the motor speed will be adjusted to 0, and an abnormal display signal will be output.

[0070] The n is a preset integer greater than or equal to 2.

[0071] In this embodiment, the record of n consecutive speed drops can be set to 2 times, 3 times, or other specific data. If there are several consecutive speed drops but the effective current value I does not decrease, it indicates that the water jet outlet may not be due to a blockage caused by precipitated crystal salts, but may be due to other unexpected situations that cause the water jet outlet to be blocked over a large area. This results in the effective current value I remaining unchanged or increasing even if the motor speed decreases. In this case, adjusting the motor speed to the lowest value or reducing it to 0 can avoid unexpected situations caused by abnormal water jet pressure.

[0072] Example 2:

[0073] Based on the above embodiment 1, this embodiment provides an alarm method for a dual-piston pump type medical water jet, which is applicable to the pressure adjustment method of any of the dual-piston pump type medical water jets described above. In the S2 of the pressure adjustment method, in the relationship f(V,I) under the target water jet pressure P0, the target water jet pressure includes at least two types: alarm target water jet pressure and pressure adjustment target water jet pressure.

[0074] In step S1 of the pressure regulation method, after the motor speed is adjusted to V0, or after the motor speed is changed in step S3 of the pressure regulation method, it is necessary to obtain the alarm current Im based on the relationship f(V, I) set according to the alarm target water jet pressure and the adjusted motor speed. The effective value of the current I at the current speed is compared with the alarm current Im. If the effective value of the current I at the current speed is greater than or equal to the alarm current Im, an alarm display signal is output.

[0075] In this embodiment, after the motor speed is adjusted to V0 in S1 and the motor speed changes in S3, the alarm current corresponding to the changed motor speed is obtained according to the relationship f(V, I) set by the alarm target water jet pressure. This current is then compared with the actual effective current value I. If the effective current value I at the current speed is greater than the alarm current Im, it indicates that the water jet pressure corresponding to the effective current value I at the current speed is actually greater than the alarm target water jet pressure. In this case, an alarm needs to be triggered immediately to inform the user.

[0076] In this embodiment, the alarm target water jet pressure is a safety limit value for product application. The alarm target water jet pressure is higher than the pressure regulating target water jet pressure. In this embodiment, it is specifically 8MPa. Technicians can set the alarm target water jet pressure to other specific values ​​as needed, such as 9MPa or 10MPa. Examples will not be elaborated here.

[0077] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A pressure adjustment method for a dual-piston pump type medical water jet, characterized in that, Includes the following steps: S1. Adjust the motor speed to the preset speed V0 and obtain the effective current value I of the motor in real time; S2. Based on the preset speed V0 of the motor and the relationship f(V, I) under several different target water jet pressures P0 obtained in advance, obtain the target current I0 corresponding to the preset speed V0. The f(V, I) is: the mapping relationship between motor speed V and effective current value I under different blockage states of the water outlet when the water jet pressure is maintained at P0. The relationship f(V, I) under the target water jet pressure P0 is obtained according to the following method: S21. Install a water pressure sensor at the outlet of the medical water jet to measure the real-time water pressure value P, and adjust the motor speed to the preset speed V0. S22. Adjust the preset speed V0 of the motor to several preset speeds V1 to Vn, change the degree of blockage at the outlet, until the real-time water pressure value P measured by the water pressure sensor is adjusted to the target water jet pressure P0 each time, record the effective current value when the motor speed is adjusted from V0 to V1 to Vn and the real-time water pressure value P is equal to the target water jet pressure P0. S23. Establish a rectangular coordinate system with the motor speed on the horizontal axis and the effective current value on the vertical axis. Based on V1 to Vn in S22 and the coordinate points of several corresponding effective current values, draw the mapping curve of the relationship f(V, I). The motor's speed in the Cartesian coordinate system is the motor's rotational speed. S3. Calculate the difference between the target current I0 and the effective current value I, and compare it with the preset threshold. If the absolute value of the difference is less than the preset threshold, the motor speed V is kept at the preset speed V0. If the absolute value of the difference is greater than the preset threshold and I is greater than I0, then reduce the motor speed. If the absolute value of the difference is greater than the preset threshold and I is less than I0, then the motor speed is increased. S4. Take the changed motor speed as the new preset speed V0, and repeat S1 to S3 until the absolute value of the difference between the target current I0 and the effective current value I is less than the preset threshold.

2. The pressure adjustment method for the dual-piston pump type medical water jet according to claim 1, characterized in that, In step S1, the effective current value I of the motor needs to be obtained based on the real-time current value of the motor and the position of the piston driven by the rotation of the motor. The method for obtaining this value is as follows: The piston position is effectively sampled by a position acquisition sensor or an angle encoder set on the motor shaft. At the same time, the real-time current value of the motor is sampled. If the piston is in the stage of generating water pressure in the compression pump chamber from the starting position A to the ending position B, or if the real-time current value sampling data shows a continuous upward trend, it is determined that the motor is under load. At this time, the current corresponding to the stroke of the piston driven by the motor from point A to point B can be used as the effective current value I after feature extraction.

3. The pressure adjustment method for the dual-piston pump type medical water jet according to claim 2, characterized in that, The stroke of the piston driven by the motor from point A to point B is the middle section of the entire piston stroke when the motor is under load.

4. The pressure adjustment method for the dual-piston pump type medical water jet according to claim 1, characterized in that, In S2, there is at least one set of relationships f(V, I) under the target water jet pressure P0 based on the product set pressure value.

5. The pressure adjustment method for the dual-piston pump type medical water jet according to claim 1, characterized in that, When it is necessary to obtain the relationship f(V, I) under different target water jet pressures P0, the motor speed needs to be adjusted to the preset speed V0 first, and then the degree of blockage at the outlet is changed so that the water pressure value P measured by the water pressure sensor installed at the outlet is the target water jet pressure P0 for this time. Then, steps S22 and S23 are repeated.

6. The pressure adjustment method for the dual-piston pump type medical water jet according to claim 1, characterized in that, It also includes S5, recording the specific values ​​of the motor speed that changed in S4, and the difference between the target current I0 and the effective current value I; If the speed decreases continuously for n times in the record, and the difference between the target current I0 and the effective current value I remains unchanged or increases, then the motor speed will be adjusted to the lowest preset speed V3, or the motor speed will be adjusted to 0, and an abnormal display signal will be output. n is a preset integer.

7. An alarm method for a dual-piston pump type medical water jet, adapted to the pressure adjustment method of the dual-piston pump type medical water jet as described in any one of claims 1-6, characterized in that, In the pressure regulation method S2, the relationship f(V,I) under the target water jet pressure P0 includes at least two types of target water jet pressure: alarm target water jet pressure and pressure regulation target water jet pressure. In step S1 of the pressure regulation method, after the motor speed is adjusted to V0, or after the motor speed is changed in step S3 of the pressure regulation method, it is necessary to obtain the alarm current Im based on the relationship f(V, I) set according to the alarm target water jet pressure and the adjusted motor speed. The effective value of the current I at the current speed is compared with the alarm current Im. If the effective value of the current I at the current speed is greater than or equal to the alarm current Im, an alarm display signal is output.

8. The alarm method for the dual-piston pump type medical water jet according to claim 7, characterized in that, The alarm target water jet pressure is a safety limit for the product application, and the alarm target water jet pressure is higher than the pressure regulating target water jet pressure.

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