A syringe pump testing system and method

Abstract

The application discloses an injection pump testing system and method, and relates to the field of testing, which comprises the following steps: connecting an injection pump with an electromagnetic valve through a pipeline; connecting a pressure sensor with the electromagnetic valve through a pipeline; connecting a weighing sensor with the electromagnetic valve through a pipeline; and controlling the connection position of the injection pump, the pressure system, the weighing system and the circuit system by a PLC. When testing the pressure of the injection pump, the injection pump is switched to the position connected with the pressure sensor; when testing the accuracy and stability of the flow of the injection pump, the injection pump is switched to the position connected with the weighing sensor; and when in a non-testing state, the electromagnetic valve always keeps the injection pump connected with waste liquid. The application realizes online detection of the flow stability, pressure stability and sealing device of the pump, and can automatically calculate and judge whether the result meets the requirements.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of injection pump testing, in particular to an injection pump testing system and a testing method. BACKGROUND

[0002] Injection pumps are mainly applied in the medical industry, but there are also non-medical injection pumps, such as micro-injection pumps for laboratories and industrial injection pumps. No matter which aspect of injection pumps is applied, it needs to accurately deliver liquid and ensure the sealing of the injection pump, especially in the medical industry, which needs to accurately control the infusion speed, infusion volume and monitor the pressure, etc.

[0003] Therefore, the testing of the injection pump is particularly important, mainly the testing of parameters such as flow stability, accuracy, pressure resistance, etc. The accuracy and stability of the flow of the injection pump are two very important testing indicators, which are key parameters to ensure the accurate transportation of the injection pump. Pressure testing is also one of the main performances of the pump, which needs to judge the stability of the pressure during the process of leaving the factory and using, troubleshoot faults and play an important reference role in the accuracy of data.

[0004] The existing devices for testing injection pumps mainly include pressure gauges and flowmeters, etc. These testing methods need to build a testing platform when used, manually calculate the results, and need to be calibrated regularly. In particular, the performance of the injection pump is tested during use, which brings a lot of inconvenience to the testers and users.

[0005] Chinese patent CN101470036B discloses an injection pump blocking pressure detection processing device and method. The pressure sensor is fixed on the base, and the force transmission element is fixed on the pressure sensor, and the first end of the force transmission element is pre-pressed on the end of the screw rod in the axial direction, and the axial pressure of the screw rod is transmitted to the pressure sensor. The injection pump blocking pressure detection processing method mainly includes: detecting the injection pump blocking pressure, controlling the stepping motor according to the difference between the blocking pressure and the set value, and pre-pressing the force transmission element on the end face of the screw rod in the step of detecting and processing the injection pump blocking pressure.

[0006] Chinese patent CN102266600A discloses an injection pump and an injection pump pressure detection system. The pressure detection system is connected with the flange on the injector shell, and the pressure detection device detects the pressure inside the injector by detecting the pressure from the flange, that is, indirectly detects the pressure change of the injector perfusion by detecting the pressure transmitted to the injector shell by the injector.

[0007] However, patents CN101470036B and CN102266600A mainly indirectly test the internal pressure of the injection pump through the screw rod and the flange part, which has limitations and errors.

[0008] The Chinese patent CN107743733B discloses a hydraulic pump flow testing device, which comprises a three-position four-way electromagnetic valve, a flow sensor, a PLC, a measurement and control computer, the three-position four-way electromagnetic valve is a K-type neutral switching valve, and flow path switching is realized by opening and power-off; the flow sensor is a pulse output type flow sensor, and mainly measures the flow of an oil flow path; the PLC has a high-speed counting function, can read and count the flow, and performs data calculation; the measurement and control computer contains measurement and control software, and can read, calculate, display and store the values in the PLC. However, the equipment is relatively complex, the cost is high, and the device does not have wide popularization and convenience. SUMMARY

[0009] In order to solve the problems of inaccurate injection pump flow monitoring in the prior art, the present application provides an injection pump testing system and a testing method.

[0010] In order to achieve the purpose of the present application, the technical scheme adopted by the present application is as follows:

[0011] An injection pump testing system comprises an injection pump, an electromagnetic valve, a pressure system, a weighing system and a circuit system; the injection pump is connected with the electromagnetic valve through a pipeline; the pressure system comprises a pressure sensor, and the pressure sensor is connected with the electromagnetic valve through a pipeline; the weighing system comprises a weight sensor, and the weight sensor is connected with the electromagnetic valve through a pipeline; the circuit system comprises a PLC, and the PLC controls the electromagnetic valve to switch the connection positions of the injection pump, the pressure system, the weighing system and the circuit system.

[0012] Further, a vent valve is arranged at the end of the pressure sensor, and the PLC controls the operation cycles of the vent valve.

[0013] Further, a waste liquid bottle is connected with the electromagnetic valve through a pipeline.

[0014] Further, the circuit system further comprises a measurement and control computer and an AD conversion module, and the data information in the pressure sensor and the weight sensor is transmitted to the measurement and control computer for data processing through the AD conversion module.

[0015] Further, the AD conversion module receives the analog calculation results of the pressure sensor and the weight sensor, and transmits the analog calculation results to the measurement and control software in the measurement and control computer through analog-digital conversion, and the measurement and control software displays the data calculation results correspondingly after receiving the signals.

[0016] Further, the weighing system further comprises a first PLC module for automatically weighing the mass of liquid in the same time interval.

[0017] Further, the pressure system further comprises a second PLC module for controlling the flow rate of liquid in the injection pump and a pump module, and the pump module controls the flow path connection of the injection pump by switching the electromagnetic valve through the PLC control.

[0018] Furthermore, the data processing module within the measurement and control computer includes an accuracy judgment module and a stability judgment module. The accuracy judgment module is used to judge the accuracy of the flow rate of the injection pump, and the stability judgment module is used to judge the stability of the injection pump.

[0019] A method for testing an infusion pump, comprising the following steps:

[0020] Step S1: Switch the PLC-controlled solenoid valve to the position where the injection pump is connected to the weight sensor;

[0021] Step S2: Set the flow rate L1 to be measured on the syringe pump, and set the number of measurement repetitions n on the measurement and control computer. At this time, the PLC module in the weight sensor device will automatically count n times according to the settings of the measurement and control computer, and record n ​​identical time intervals t. d The cumulative weights of the liquids below are m1, m2, m3 up to m n ;

[0022] Step S3: The PLC module in the weight sensor device automatically calculates the weight difference between adjacent cumulative weights: m1-0, m2-m1, m3-m2, up to m n -m n-1 ;

[0023] Step S4: Calculate each time interval t according to the formula ρ=m / v. d The volumes of the injected liquid are V1 = (m1-0)*ρ, V2 = (m2-m1)*ρ, and V3 = (m3-m2)*ρ until V n =(m n -m n-1 )*ρ, which represents V1, V2, V3 up to V n Compare with the theoretical value V0=L1*t respectively d Compare the values ​​and select the V with the largest difference. x As the basis for error calculation, the system automatically displays the error calculation result as: E=(V x -V0) / V0*100%, if E>0.5%, the flow rate is judged to be inaccurate, i.e., unqualified; if E≤0.5%, the flow rate is judged to be accurate, i.e., qualified.

[0024] Step S5: Calculate the weight difference M for n times according to the RSD formula: m1-0, m2-m1, m3-m2 until m n -m n-1 The RSDn value is used as the basis for judging the flow stability; if the RSDn value is less than or equal to 0.5%, the flow of the syringe pump is judged to be stable, that is, qualified; if the RSD value is greater than 0.5%, the flow of the syringe pump is judged to be unstable, that is, unqualified.

[0025] Step S6: through the judgment of step S4 and step S5, if at least one of the judgment results in step S4 and step S5 is judged unqualified, the injection pump is unqualified; if the judgment results in step S4 and step S5 are both judged qualified, the injection pump is qualified.

[0026] Further, when testing the pressure of the injection pump, the electromagnetic valve automatically switches the injection pump to the position connected with the online pressure sensor; when testing the accuracy and stability of the flow of the injection pump, the electromagnetic valve automatically switches the injection pump to the position connected with the weight sensor; when in a non-testing state, the electromagnetic valve always keeps the injection pump connected with the waste liquid.

[0027] Compared with the prior art, the beneficial effects of the present application are embodied in:

[0028] (1) The present application switches the injection pump to the position connected with different sensors in different situations through the electromagnetic valve, realizes the direct testing of the pressure generated by the system flow path of the injection pump in operation, and the technical effect that the pressure can more truly reflect the system pressure of the injection pump rather than the thrust.

[0029] (2) The present application mainly monitors the flow through the online weight sensor, and increases the calculation and testing method, realizes the technical effect of automatically monitoring the flow of the injection pump; the injection pump testing device and method has high automation degree, simple operation, wide application range, low cost, and can improve the testing efficiency of the tester.

[0030] (3) The present application is provided with a data processing module in the measurement and control computer, not only provides an automatic calculation result method, but also has data storage and searching functions; and the accurate judgment module and the stable judgment module in the data processing module can monitor and judge the accuracy and stability of the injection pump, and further judge whether the injection pump is qualified; realizes the online detection of the flow stability, pressure stability and sealing device of the pump, and can automatically calculate and judge whether the result meets the requirements. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 is a block schematic diagram of the testing principle of the present application;

[0032] Figure 2 is a principle diagram of the flow testing system of the present application;

[0033] Figure 3 is a pressure testing curve schematic diagram of a certain time period in the present application;

[0034] Figure 4 is a pressure testing curve schematic diagram of pressure sudden drop at a certain time point in the present application;

[0035] Figure 5It is a second PLC module inside the pressure sensor of the application.

[0036] Reference signs: 1. electromagnetic valve; 2. pressure sensor; 3. injection pump; 4. weight sensor; 5. waste liquid bottle. DETAILED DESCRIPTION

[0037] In order to make the purpose and technical scheme of the application clearer, the technical scheme of the application will be described clearly and completely below in combination with examples.

[0038] Example 1

[0039] As shown in a kind of injection pump 3 test system shown in Figure 1 And Figure 2 , including injection pump 3, electromagnetic valve 1, pressure system, weighing system and circuit system;The electromagnetic valve 1 is three-position four-way electromagnetic valve 1, can control pump flow path connection position, and always two-way communication;The injection pump 3 is connected with electromagnetic valve 1 by pipeline;The pressure system includes pressure sensor 2 and control pump module, the pressure sensor 2 is connected with electromagnetic valve 1 by pipeline, can test pump pressure stability on line and automatically display result;The weighing system includes weight sensor 4, the weight sensor 4 is connected with electromagnetic valve 1 by pipeline, and has automatic calculation function, can calculate flow stability when liquid passes, whether it is connected to injection pump 3 liquid flow path by electromagnetic valve 1 control;The circuit system includes PLC, the PLC controls electromagnetic valve 1 to switch injection pump 3 and the connection position of pressure system, weighing system, circuit system.

[0040] It also includes vent valve and waste liquid bottle 5, the vent valve is located at the end of pressure sensor 2, and the PLC controls the running number of vent valve, so as to achieve the purpose of controlling pressure, and PLC has calculation function, which will summarize the test results and calculate, PLC has the function of anti-control injection pump 3, so that injection pump 3 runs or stops according to specified flow rate. The electromagnetic valve 1 is connected with waste liquid bottle 5 by pipeline.

[0041] The circuit system further includes measurement and control computer and AD conversion module, data information in the pressure sensor 2 and weight sensor 4 is transmitted to measurement and control computer for data processing through AD conversion module. After the AD conversion module receives the analog calculation results of the pressure sensor 2 and the weight sensor 4, the analog-digital conversion is transmitted to the measurement and control software in the measurement and control computer, and the measurement and control software displays the data calculation results after receiving the signal. The data processing module in the measurement and control computer includes accurate judgment module and stable judgment module, the accurate judgment module is used to judge the flow accuracy of injection pump 3, and the stable judgment module is used to judge the stability of injection pump 3.

[0042] The weighing system also includes a first PLC module for automatically weighing the liquid mass within the same time interval. The pressure system also includes a second PLC module for reverse control of the liquid flow rate in the injection pump 3. The control pump module controls the switching of the solenoid valve 1 through the PLC, thereby controlling the flow path connection of the injection pump 3, and the control pump module uses the PLC to realize the reverse control of the flow rate of the injection pump 3.

[0043] A test method for an injection pump 3, the test steps include:

[0044] Step S1: Switch the solenoid valve controlled by the PLC to the position where the injection pump 3 is connected to the weight sensor 4;

[0045] Step S2: Set the flow rate L1 of the syringe pump 3 to be measured, and set the number of measurement repetitions n on the measurement and control computer. At this time, the PLC module in the weight sensor 4 will automatically count n times according to the settings of the measurement and control computer, and record n ​​identical time intervals t. d The cumulative weights of the liquids below are m1, m2, m3 up to m n ;

[0046] Step S3: The PLC module inside the weight sensor 4 device automatically calculates the weight difference between adjacent cumulative weights: m1-0, m2-m1, m3-m2 until m n -m n-1 ;

[0047] Step S4: Calculate each time interval t according to the formula ρ=m / v. d The volumes of the injected liquid are V1 = (m1-0)*ρ, V2 = (m2-m1)*ρ, and V3 = (m3-m2)*ρ until V n =(m n -m n-1 )*ρ, which represents V1, V2, V3 up to V n Compare with the theoretical value V0=L1*t respectively d Compare the values ​​and select the V with the largest difference. x As the basis for error calculation, the system automatically displays the error calculation result as: E=(V x -V0) / V0*100%, if E>0.5%, the flow rate is judged to be inaccurate, i.e., unqualified; if E≤0.5%, the flow rate is judged to be accurate, i.e., qualified.

[0048] Step S5: Calculate the weight difference M for n times according to the RSD formula: m1-0, m2-m1, m3-m2 until m n -m n-1The RSDn value is used as the basis for judging the flow stability; if the RSDn value is less than or equal to 0.5%, the flow of the syringe pump is judged to be stable, that is, qualified; if the RSD value is greater than 0.5%, the flow of the syringe pump is judged to be unstable, that is, unqualified.

[0049] Step S6: Based on the judgments in Steps S4 and S5, if at least one of the judgment results in Steps S4 and S5 is unqualified, then the injection pump is unqualified; if both the judgment results in Steps S4 and S5 are qualified, then the injection pump is qualified.

[0050] When testing the pressure of syringe pump 3, solenoid valve 1 automatically switches syringe pump 3 to the position connected to online pressure sensor 2; when testing the accuracy and stability of syringe pump 3's flow rate, solenoid valve 1 automatically switches syringe pump 3 to the position connected to weight sensor 4; when not in testing mode, solenoid valve 1 always keeps syringe pump 3 connected to waste liquid. The unit for setting the measured flow rate L1 of syringe pump 3 can be μL / h or mL / min; the number of measurement repetitions n can be 3, 5, 7, 11, or 14; the same time interval t... d The unit of measurement is available in three options: seconds (s), minutes (min), and hours (h), to meet the testing requirements of different flow rates; the accuracy of the weight sensor 4 can reach 0.1 mg.

[0051] The specific operating principle is as follows: the PLC controls the switching of the three-position four-way valve to connect the injection pump 3 to the pressure sensor 2 device, and the flow rate rise curve inside the PLC is selected through the measurement and control software, such as... Figure 5 As shown, two flow operation modes are selectable: parabolic and constant flow. When the pressure of the syringe pump 3 rises to a specified pressure, such as 10 MPa, the PLC controls the syringe pump 3 to stop running and maintains a sealed connection between the syringe pump 3 and the online pressure sensor 2 system for a set time period of 10 minutes; that is, the PLC controls the end vent valve to be in the closed state. After the system reaches the 10-minute time, the three-position four-way valve switches the pump to connect to the flow path of the waste liquid bottle 5, and the pressure of the online pressure sensor 2 device is released. At this time, the measurement and control software records as follows: Figure 3 The curve shown. The monitoring and control software automatically calculates the pressure change value ΔP and the pressure change rate ΔP / 10min within a specified time of 10 minutes. Based on the specified pressure change value and pressure change rate, the monitoring and control software automatically identifies whether the sealing performance of this injection pump 3 meets the requirements; when the system suddenly experiences a situation like this within the 10-minute sealing time... Figure 4The curve shown, i.e. pressure sudden drop at a certain time point, the PLC will automatically calculate the instantaneous pressure drop, when the instantaneous pressure drop exceeds 0.5Mpa / s, it is judged that the injection pump 3 sealing failure. When the pressure of the injection pump 3 exceeds the set pressure value, the PLC controls the vent valve at the end of the online pressure sensor 2 system, the PLC automatically calculates the number of rotating vent valve according to the required pressure release size, so that the system pressure is kept at the set value.

[0052] The above is only the embodiment of the present application, which is described in detail and specifically, but it should not be understood as a limitation to the scope of the patent of the present application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of protection of the present application.

Claims

1. A syringe pump testing system, characterized in that, This includes syringe pumps, solenoid valves, pressure systems, weighing systems, and electrical systems. The injection pump is connected to the solenoid valve via a pipeline; The pressure system includes a pressure sensor, which is connected to a solenoid valve via a pipeline. The weighing system includes a weight sensor, which is connected to a solenoid valve via a pipeline. The circuit system includes a PLC, which controls the solenoid valve to switch the connection positions of the injection pump with the pressure system, the weighing system, and the circuit system. The testing of an infusion pump based on an infusion pump testing system includes the following steps: Step S1: Switch the PLC-controlled solenoid valve to the position where the injection pump is connected to the weight sensor; Step S2: Set the flow rate L1 to be measured on the syringe pump, and set the number of measurement repetitions n on the measurement and control computer. At this time, the PLC module in the weight sensor device will automatically count n times according to the settings of the measurement and control computer, and record n ​​identical time intervals t. d The cumulative weights of the liquids below are m1, m2, m3 up to m n ; Step S3: The PLC module in the weight sensor device automatically calculates the weight difference between adjacent cumulative weights: m1-0, m2-m1, m3-m2, up to m n -m n-1 ; Step S4: Calculate each time interval t according to the formula ρ=m / v. d The volumes of the injected liquid are V1 = (m1-0)*ρ, V2 = (m2-m1)*ρ, and V3 = (m3-m2)*ρ until V n =(m n -m n-1 )*ρ, which represents V1, V2, V3 up to V n Compare with the theoretical value V0=L1*t respectively d Compare the values ​​and select the V with the largest difference. x As the basis for error calculation, the system automatically displays the error calculation result as: E=(V x -V0) / V0*100%, if E>0.5%, the flow rate is judged to be inaccurate, i.e., unqualified; if E≤0.5%, the flow rate is judged to be accurate, i.e., qualified. Step S5: Calculate the weight difference M for n times according to the RSD formula: m1-0, m2-m1, m3-m2 until m n -m n-1 The RSDn value is used as the basis for judging the flow stability; if the RSDn value is less than or equal to 0.5%, the flow of the syringe pump is judged to be stable, that is, qualified; if the RSD value is greater than 0.5%, the flow of the syringe pump is judged to be unstable, that is, unqualified. Step S6: Based on the judgments in Steps S4 and S5, if at least one of the judgment results in Steps S4 and S5 is unqualified, then the injection pump is unqualified; if both the judgment results in Steps S4 and S5 are qualified, then the injection pump is qualified.

2. The syringe pump testing system according to claim 1, characterized in that, It also includes a vent valve, which is located at the end of the pressure sensor, and the PLC controls the number of rotations of the vent valve.

3. The syringe pump testing system according to claim 1, characterized in that, It also includes a waste liquid bottle, and the solenoid valve is connected to the waste liquid bottle through a pipeline.

4. The syringe pump testing system according to claim 1, characterized in that, The circuit system also includes a measurement and control computer and an AD conversion module. The data information from the pressure sensor and the weight sensor is transmitted to the measurement and control computer for data processing through the AD conversion module.

5. The syringe pump testing system according to claim 4, characterized in that, The AD conversion module receives the analog calculation results from the pressure sensor and the weight sensor, and transmits them to the measurement and control software in the measurement and control computer through analog-to-digital conversion. After receiving the signal, the measurement and control software displays the data calculation results accordingly.

6. The syringe pump testing system according to claim 1, characterized in that, The weighing system also includes a first PLC module for automatically weighing the mass of liquid within the same time interval.

7. The syringe pump testing system according to claim 1, characterized in that, The pressure system also includes a second PLC module and a control pump module for controlling the liquid flow rate in the injection pump. The control pump module controls the flow path connection of the injection pump by switching the solenoid valve through the PLC.

8. The syringe pump testing system according to claim 4, characterized in that, The data processing module within the measurement and control computer includes an accuracy judgment module and a stability judgment module. The accuracy judgment module is used to judge the accuracy of the flow rate of the injection pump, and the stability judgment module is used to judge the stability of the injection pump.

9. The syringe pump testing system according to claim 1, characterized in that, When testing the pressure of the syringe pump, the solenoid valve automatically switches the syringe pump to the position connected to the pressure sensor; when testing the accuracy and stability of the syringe pump flow rate, the solenoid valve automatically switches the syringe pump to the position connected to the weight sensor; when not in testing mode, the solenoid valve always keeps the syringe pump connected to the waste liquid.

Images