High-precision integrated respirator tester calibration device

Abstract

The utility model provides a high-precision integrated respirator tester calibration device. The comprehensive calibration of flow, tidal volume, static pressure, respiratory rate, airway peak pressure, positive end-expiratory pressure and oxygen concentration parameters is realized through integrated design. The device comprises flow, pressure and oxygen concentration calibration function and control components, and adopts a layered and partitioned layout, so that the space utilization and the maintenance convenience are optimized. In particular, an active piston type flow standard device is introduced as a high-precision gas source without depending on external gas supply, so that the stability and precision of flow calibration are remarkably improved. Regional modular design facilitates replacement of standard gas cylinders, adjustment of exhaust assemblies and maintenance of precision instruments, and installation of electrical elements facilitates heat dissipation and maintenance. The integrated design is compact and efficient, and a high-precision and stable-performance solution is provided for calibration of the respirator tester.

Description

Technical Field

[0001] The utility model relates to a calibration device for a medical testing instrument, in particular to a calibration device for a ventilator tester. Background Art

[0002] The metrology work of medical instrument equipment is a key component of hospital management. In the fields of modern medical diagnosis, treatment, and scientific research, a large number of medical instrument equipment are widely used, and quite a part of them belong to measuring instruments, which become an important material basis for medical work. With the continuous progress of medical technology, the ventilator, an important medical device, has been widely used in clinical treatment. However, the performance and quality of the ventilator have a crucial impact on the life safety and treatment effect of patients. Therefore, it is necessary to use a ventilator tester to detect the ventilator according to requirements. The ventilator tester is a dedicated medical metrology quality control device for ventilators and anesthetic machines. According to the evaluation of international authoritative institutions, ventilators and anesthetic machines belong to one of the equipment categories with the highest clinical risks among the medical equipment in use in hospitals. Formulating a scientific and reasonable quality control plan for the in-use ventilators and anesthetic machines and carrying out regular metrological calibration are key tasks in the preventive maintenance part of quality control and also the fundamental means to ensure the accuracy of the measured values of relevant medical equipment.

[0003] As a medical device used to detect and evaluate the performance and quality of a ventilator, the main function of the ventilator tester is to detect and evaluate various performance indicators of the ventilator, such as flow rate, pressure, oxygen concentration, etc., so as to ensure the performance and quality of the ventilator. The accuracy and reliability of these indicators are directly related to the life safety and treatment effect of patients. Therefore, it is extremely necessary to calibrate the ventilator tester precisely.

[0004] At present, the ventilators in hospitals are usually calibrated by a ventilator detector, generally once a year. However, the calibration of the ventilator tester is often ignored, so the entire traceability system is still not perfect, which is undoubtedly an indirect safety hazard for the ventilator. Ensuring the accuracy of the gas flow rate, pressure, respiratory frequency, and oxygen concentration measured by the ventilator tester is the core element to ensure the safety and reliability of the patient's treatment process.

[0005] The calibration device of the ventilator tester needs to calibrate flow rate, tidal volume, static pressure, respiratory rate, peak airway pressure, positive end-expiratory pressure, and oxygen concentration. Among them, as in Chinese patent document CN115920184A, the oxygen concentration calibration module uses the standard gas method for flow calibration. This patent document uses a fan as the flow generating device and adjusts the flow rate through an electric valve. However, overall, there are still some common deficiencies in the calibration devices of ventilator testers in the industry at present: ① The integration degree is not high, and several parameters are often calibrated by multiple independent instruments; ② The device size is large, occupying a large space; ③ An external gas source is required. Some devices use externally high-pressure gas after decompression as the gas source and rely on the external gas source; ④ The performance and stability are poor. Most of the industry devices use thermal flow meters for flow calibration. The zero-point stability of thermal flow meters is poor, the performance is extremely unstable, the error is large after long-term use, and the cost is high. Summary of the Invention

[0006] The purpose of the present utility model is to propose a calibration device for a ventilator tester, which has the characteristics of high precision and integration, so as to overcome the above deficiencies in the industry status quo. The device integrates flow parameter calibration, respiratory rate calibration, pressure parameter calibration, oxygen concentration parameter calibration and a control system. The flow parameter calibration is to test and calibrate the static flow rate, tidal volume, and respiratory rate. The pressure parameter calibration is to test and calibrate the static pressure, airway pressure, and positive end-expiratory pressure. The oxygen concentration parameter calibration is to test and calibrate 21% - 100% (volume fraction). The control system uses a controller and control software to detect the static flow rate, tidal volume, respiratory rate, static pressure, peak airway pressure, positive end-expiratory pressure, and oxygen concentration, and perform process control and data processing.

[0007] The device is specifically designed with partition modularization:

[0008] (1) Standard gas cylinder group area: The standard gas cylinders are installed on the front of the device, which is convenient for the occasional replacement of the standard gas cylinders.

[0009] (2) Exhaust component layer: An exhaust port valve, a simulated lung, etc. are installed in this area. The parameters of the simulated lung can be adjusted through the window at the calibration station of the ventilator tester.

[0010] (3) Standard gas outlet valve group layer: This layer mainly installs the standard gas cylinder outlet valve group, including solenoid valves, pressure reducing valves, pressure transmitters, first flow meters, etc. The pressure and flow rate of the standard gas outlet can be adjusted through the pressure reducing valve group from the right door.

[0011] (4) Precision instrument layer: A second flow meter, a precision pressure transmitter, etc. are installed in this area. The second flow meter and the precision pressure transmitter can be regularly calibrated and disassembled from the front or the right side, which is convenient for maintenance.

[0012] (5) Active piston type flow standard device area: Vertically installed in the left area at the back of the device, with a large space, facilitating the maintenance and repair of larger components such as cylinders and electric cylinders.

[0013] (6) Cylinder solenoid valve layer: Cylinder inlet and outlet gas solenoid valves and fans are installed in this area.

[0014] (7) Electrical component installation area: This area is the centralized installation area of electrical components within the device, and the electrical component installation area is installed on the upper, lower, left, right, front or back of the device, isolated from other instruments, and main high-voltage electrical components such as servo drivers, leakage protection switches, and electromagnetic contactors are installed, which can reduce interference with other instruments.

[0015] (8) Device air inlet area: The air inlet is installed at the bottom of the device to ensure that the state of the inlet gas is consistent with the environment.

[0016] The technical solution of the embodiment of the present utility model has at least the following advantages and beneficial effects:

[0017] Through the novel hierarchical and zonal integrated structure design, the present utility model has a compact structure and a small volume. This highly integrated design calibrates parameters such as flow rate, tidal volume, static pressure, respiratory rate, peak airway pressure, positive end-expiratory pressure, and oxygen concentration in one device, with a relatively small volume. The active piston type flow standard device is used to provide the gas source and flow rate traceability, without relying on external gas sources, with higher flow calibration accuracy and better stability. Moreover, as a flow generation and traceability device, the active piston type flow standard device has stable flow and a small maximum allowable error of flow rate. Description of the Drawings

[0018] In order to more clearly illustrate the technical solution of the embodiment of the present utility model, the drawings required to be used in the embodiment will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present utility model, and therefore should not be regarded as a limitation of the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0019] Figure 1 is the three-dimensional structure schematic diagram of the present utility model;

[0020] Figure 2 is the rear view of the internal structure of the present utility model;

[0021] Icons: 1 - Frame, 2 - Display stand, 3 - Exhaust component layer, 31 - Upright platform, 311 - Detection instrument connection port, 312 - Power socket, 313 - Data cable interface, 32 - Platform, 4 - Standard gas cylinder group area, 41 - Standard gas cylinder, 5 - Active piston type flow standard device area, 51 - Active piston type flow standard device, 511 - Large active piston type flow standard device, 5111 - Large piston cylinder, 5112 - Large drive electric cylinder, 512 - Small active piston type flow standard device, 5121 - Small piston cylinder, 5122 - Small drive electric cylinder, 6 - Electrical component installation area, 7 - Valve and meter installation area, 71 - Standard gas outlet valve group layer, 72 - Precision instrument layer, 73 - Cylinder solenoid valve layer. Detailed implementation

[0022] Please refer to Figures 1 to 2 , the present utility model provides a high-precision integrated calibration device for a ventilator tester, aiming to calibrate the ventilator tester by precisely controlling and measuring parameters such as gas flow and pressure, and ensuring the accuracy and reliability of its measurement results. The following is a detailed description of the specific implementation of this device.

[0023] The overall structure of this device is as shown in Figures 1 to 2 , and mainly includes a frame 1, a display stand 2, an exhaust component layer 3, a standard gas cylinder group area 4, an active piston type flow standard device area 5, an electrical component installation area 6, and a valve and meter installation area 7, etc. These parts are reasonably arranged and connected to jointly form the overall architecture of the high-precision integrated calibration device for the ventilator tester.

[0024] Furthermore, the frame 1, as the support structure of the entire device, is made of strong and durable metal materials, with good load-bearing capacity and stability. The design of the frame 1 fully considers the installation, maintenance, and transportation requirements of the equipment, ensuring that each component can be firmly installed in the designated position. The frame 1 can be welded from conventional section steels such as angle steels. Generally, a sheet metal surface needs to be set on the frame 1 for encapsulation. The components inside the frame are in a closed and protected space. Doors or windows for maintenance can be installed on each surface of the frame as needed.

[0025] Furthermore, the display stand 2 is installed at the upper left of the frame 1, which is convenient for operators to observe and operate. The display stand 2 is equipped with a touch screen or a button-type operation interface, used to display various parameters (such as flow rate, pressure, etc.) and status information during the calibration process, and at the same time supports inputting calibration instructions and setting calibration parameters.

[0026] Further, the exhaust component layer 3 is arranged at the upper right of the frame 1. A detection instrument connection port 311 is arranged in the exhaust component layer 3 for connecting an external detection instrument. The detection instrument connection port 311 is communicated with the main pipeline inside the frame 1. In this field, there are numerous pipelines, and many pipes are required to connect various valves, meters, instruments, etc. Finally, they will converge into a main pipeline, and this main pipeline is communicated with an external ventilator tester through the detection instrument connection port 311. This main pipeline is the main pipeline.

[0027] Further, the standard gas cylinder group area 4 is installed at the lower left front inside the frame 1 for storing standard gas cylinders 41. The standard gas cylinders 41 are communicated with the main pipeline inside the frame 1 through a series of valves and pipelines. There are multiple standard gas cylinders and they are installed vertically. Such a design not only saves space but also facilitates management and replacement. The standard gas cylinders 41 are filled with a mixed gas of known concentration for gas supply during the calibration process.

[0028] Further, the active piston type flow standard device area 5 is arranged on the left of the frame 1, behind the display platform 2 and the standard gas cylinder group area 4. The active piston type flow standard device 51 in this area is installed vertically, which is beneficial to reducing the floor area and improving the stability. The active piston type flow standard device 51, the first grating scale 52, and the second grating scale 53 are arranged in this area. The active piston type flow standard device 51 includes a large active piston type flow standard device 511 and a small active piston type flow standard device 512 to meet the calibration requirements of different flow ranges. The large active piston type flow standard device 511 is connected to the first grating scale 52, and the small active piston type flow standard device 512 is connected to the second grating scale 53. The grating scale can more accurately detect the stroke of the active piston type flow standard device.

[0029] At the same time, the weights of the standard gas cylinders and the active piston type flow standard device area 5 are relatively large. By arranging them one in front and the other behind, the weight distribution of the entire device can be well balanced, improving the stability of the entire device. Coupled with the weights of other components of the device, the center of gravity of the entire device is in the middle of the device.

[0030] Both the large active piston type flow standard device 511 and the small active piston type flow standard device 512 adopt a high-precision piston structure, and generate a stable gas flow by precisely controlling the movement of the piston. In the upper part of the large active piston type flow standard device 511, there is a large piston cylinder 5111 for storing gas and providing a stable pressure source; in the lower part, there is a large driving electric cylinder 5112 for driving the large piston to move up and down to generate flow. In the upper part of the small active piston type flow standard device 512, there is a small piston cylinder 5121 for storing gas and providing a stable pressure source; in the lower part, there is a small driving electric cylinder 5122 for driving the small piston to move up and down to generate flow. The structure of the small active piston type flow standard device (512) is similar to that of the large active piston type flow standard device 511, but it is smaller in size and capacity, and is suitable for calibration in a small flow range.

[0031] Furthermore, the electrical component installation area 6 is an area where electrical components are centrally installed. The electrical component installation area 6 is installed inside the frame 1 and is set at the upper, lower, front, rear, left or right side of the frame 1, that is, it is installed at a position close to the outer surface of the frame. This installation position also facilitates the maintenance of electrical components and is conducive to the heat dissipation of electrical components during operation. In addition, it can be isolated from other instruments. Main high-voltage electrical components such as servo drivers, leakage protection switches, and electromagnetic contactors are centrally installed in the electrical component installation area 6, which can reduce interference with other instruments and improve the accuracy of the entire equipment.

[0032] Furthermore, the valve and meter installation area 7 is set on the right side of the frame 1 and is located below the exhaust component layer (3). The valve and meter installation area 7 is divided into three parts from top to bottom: the standard gas outlet valve group layer 71, the precision instrument layer 72, and the cylinder solenoid valve layer 73.

[0033] Furthermore, the electrical component installation area 6 is installed at the bottom rightmost layer or the right side of the device, that is, below or on the right side of the valve and meter installation area 7, for installing various electrical components and control circuits. These electrical components include, but are not limited to, power modules, controllers, sensor interface boards, servo drivers, leakage protection switches, electromagnetic contactors, etc. They work together to achieve the various functions of the calibration device. The main consideration for installing the electrical component installation area 6 at the bottom rightmost layer or the right side of the device is, in addition to facilitating maintenance and heat dissipation; also because the electrical components are mainly connected to the valves and meters in the valve and meter installation area 7. Considering the purpose of saving wire, it is most appropriate to set the electrical component installation area 6 next to the valve and meter installation area 7.

[0034] Further, since the standard gas cylinder 41 has a certain height, when it is installed vertically, its gas outlet is basically at a position slightly above the middle of the entire device. Therefore, it is more reasonable to set the standard gas outlet valve group layer 71 at the top of the valve table installation area 7, which can effectively save the connecting pipeline. At the same time, the standard gas cylinder 41 is connected to components such as solenoid valves, pressure reducing valves, check valves, and pressure gauges. Concentrating these components on one layer is also convenient for installation and maintenance.

[0035] Further, elements such as solenoid valves, pressure reducing valves, pressure transmitters, and first flow meters are provided in the standard gas outlet valve group layer 71. These elements are connected in series in sequence through pipelines to form a standard gas flow path. The outlet of the standard gas cylinder 41 is connected to the solenoid valve through a pipeline, and the solenoid valve is used to control the on-off of the gas. After the gas is decompressed by the pressure reducing valve, it enters the pressure transmitter for pressure measurement and continues to flow to the first flow meter for flow measurement. Finally, the gas is connected to the ventilator tester or other detection instruments to be calibrated through the main pipeline. The first flow meter adopts a non-thermal flow meter, and it can be a positive displacement flow meter, a turbine flow meter, an electromagnetic flow meter, or an ultrasonic flow meter, etc.

[0036] Further, the precision instrument layer 72 is located in the middle part of the valve table installation area 7 and is a centralized installation area for key measurement components in the calibration device. High-precision instruments such as a second flow meter and a precision pressure transmitter are installed in this layer. The second flow meter adopts a high-precision flow meter. In this embodiment, one end of the second flow meter is connected to the outlet of the active piston type flow standard device 51 through a pipeline to measure and verify the accuracy of the gas flow generated by the active piston type flow standard device. The other end of the second flow meter is connected to the precision pressure transmitter to ensure that while measuring the flow, the change in gas pressure can also be monitored in real time. The precision pressure transmitter is a sensor that can measure the gas or liquid pressure with high precision. In this device, it is used to measure the gas pressure after passing through the second flow meter and transmit the measurement result to the display console 2 for display and recording. At the same time, the precision pressure transmitter is also connected to the detection instrument connection port 311 of the exhaust component layer 3 through the main pipeline to calibrate the ventilator test instrument. The second flow meter adopts a non-thermal flow meter, and it can be a positive displacement flow meter, a turbine flow meter, an electromagnetic flow meter, or an ultrasonic flow meter, etc.

[0037] Further, the cylinder solenoid valve layer 73 is located at the bottom of the valve table installation area 7 and is a key part for controlling the gas inlet and outlet of the cylinder. Cylinder inlet and outlet solenoid valves are provided in this layer. Of course, in some embodiments, the cylinder can cooperate with a blower to perform flow calibration of the ventilator detector, so the installation position of the blower can also be set in the cylinder solenoid valve layer 73.

[0038] The cylinder solenoid valve is used to control the intake and exhaust processes of the cylinder. By precisely controlling the opening and closing times of the solenoid valve, parameters such as the gas flow rate can be precisely controlled in coordination with the movement of the cylinder piston, thereby generating a stable and repeatable gas flow rate.

[0039] Furthermore, the exhaust component layer 3 includes a vertical platform 31 and a flat platform 32. The front-mounted components on the vertical platform include a detection instrument connection port 311, a power socket 312, a data cable interface 313, etc.; An inspection window that can be opened is provided at the flat platform 32. The inspection window can adopt the form of a conventional iron sheet cover with a hinge. When the iron sheet cover is closed, other objects can also be placed on the iron sheet cover to serve as a loading platform. When the inspection window is opened, the calibration gas outlet valve group layer 71 can be inspected and maintained.

[0040] Furthermore, a placement position for the simulated lung can also be set at the position of the calibration gas outlet valve group layer 71, and the simulated lung can be operated by opening the inspection window.

[0041] Furthermore, a filtering device is provided at the intake port ends of the fan and the active piston type flow standard device 51. When the electrical component installation area 6 is installed at the bottom layer of the entire device, the filtering device can be installed in the electrical component installation area 6 and close to the right edge of the frame 1 to filter the gas entering the device, removing impurities and particulate matter therein, and protecting the precision instruments and cylinders and other components inside the device from damage. The filtering device usually consists of components such as filter screens and filter elements, and has different filtering precisions and filtering efficiencies. In this embodiment, a suitable filtering device is selected for installation and use according to the requirements of gas cleanliness and the actual situation of the device.

[0042] The calibration principle of this high-precision integrated ventilator tester calibration device is as follows:

[0043] Flow calibration: The active piston type flow standard device 51 is used as the generating device for flow rate and tidal volume, and the volumes of the grating scale and the cylinder are used as the traceability of the flow rate.

[0044] Respiratory rate calibration: The movement frequency of the cylinder piston is used as the generating device for the frequency. The reciprocating times of the cylinder piston are fed back by the speed change of the grating scale and converted into frequency as the traceability of the respiratory rate.

[0045] Pressure calibration: The cylinder is used as the generator for static pressure, airway peak pressure, and end-expiratory positive pressure, and a precision pressure gauge is used as the standard for comparative calibration

[0046] Oxygen concentration calibration: Standard gas is used as the gas source and standard source for oxygen concentration.

[0047] Maintenance and servicing: After calibration, turn off the power supply and valves of each component; regularly clean and replace the filtration device; check and maintain the working status and connections of each component; record the calibration data and conduct analysis and summary.

[0048] From the detailed description of the above calibration principle, it can be seen that this high-precision integrated ventilator tester calibration device has the advantages of compact structure, complete functions, simple operation, accurate measurement, etc. It can meet various requirements for calibrating ventilator testers and ensure the reliability and stability of calibration results.

Claims

1. An integrated calibration device for a high-precision ventilator tester, characterized in that: It includes a frame (1), a display platform (2), an exhaust component layer (3), a standard gas cylinder group area (4), an active piston type flow standard device area (5), an electrical component installation area (6), a valve and meter installation area (7), and a main pipeline; The display platform (2) is installed at the upper left of the frame (1); The exhaust component layer (3) is arranged at the upper right of the frame (1). A detection instrument connection port (311) is arranged in the exhaust component layer, and the detection instrument connection port (311) is communicated with the main pipeline; The standard gas cylinder group area (4) is installed at the lower left front inside the frame (1). Standard gas cylinders (41) are installed in the standard gas cylinder group area, and the standard gas cylinders (41) are communicated with the main pipeline; The active piston type flow standard device area (5) is arranged on the left of the frame (1) and behind the display platform (2) and the standard gas cylinder group area (4). An active piston type flow standard device (51) is arranged in the active piston type flow standard device area (5), and the active piston type flow standard device (51) is communicated with the main pipeline; The electrical component installation area (6) is an area where electrical components are centrally installed. The electrical component installation area (6) is installed inside the frame (1) and is arranged at the upper, lower, front, rear, left or right position of the frame (1); The valve and meter installation area (7) is arranged on the right side of the frame and below the exhaust component layer (3).

2. The calibration device for a high-precision integrated ventilator tester according to claim 1, characterized in that, The standard gas cylinders (41) in the standard gas cylinder group area (4) are multiple and are installed vertically.

3. The calibration device for a high-precision integrated ventilator tester according to claim 1, wherein The active piston type flow standard device (51) in the active piston type flow standard device area (5) is installed vertically.

4. An integrated high-precision calibration device for a ventilator tester according to claim 3, characterized in that, The active piston type flow standard device (51) includes a large active piston type flow standard device (511) and a small active piston type flow standard device (512).

5. An integrated high-precision calibrating device for a ventilator tester according to claim 4, characterized in that, A large piston cylinder (5111) is arranged at the upper part of the large active piston type flow standard device (511), and a large driving electric cylinder (5112) is arranged at the lower part. The large driving electric cylinder (5112) can drive the large piston of the large piston cylinder (5111) to reciprocate; A small piston cylinder (5121) is arranged at the upper part of the small active piston type flow standard device (512), and a small driving electric cylinder (5122) is arranged at the lower part. The small driving electric cylinder (5122) can drive the small piston of the small piston cylinder (5121) to reciprocate.

6. The calibration device for a high-precision integrated ventilator tester according to claim 1, characterized in that, The valve and meter installation area (7) is divided into a standard gas outlet valve group layer (71), a precision instrument layer (72), and a cylinder solenoid valve layer (73) from top to bottom.

7. An integrated high-precision calibrating device for a ventilator tester according to claim 6, characterized in that, An electromagnetic valve, a pressure reducing valve, a pressure transmitter, and a first flowmeter are arranged in the standard gas outlet valve group layer (71). The outlet of the standard gas cylinder (41) is connected in series with the electromagnetic valve, the pressure reducing valve, the pressure transmitter, and the first flowmeter through a pipeline in sequence and is finally communicated with the main pipeline.

8. The calibration device for a high-precision integrated ventilator tester according to claim 6, characterized in that, A second flowmeter and a precision pressure transmitter are installed in the precision instrument layer (72). One end of the second flowmeter is connected to the active piston type flow standard device (51), and the other end of the second flowmeter is connected to the precision pressure transmitter. The precision pressure transmitter is then connected to the detection instrument connection port (311) of the exhaust component layer (3) through the main pipeline.

9. An integrated high-precision calibration device for a ventilator tester according to claim 6, characterized in that, An electromagnetic valve for controlling the gas inlet and outlet of the active piston type flow standard device (51) is provided in the cylinder electromagnetic valve layer (73).

10. A high-precision integrated ventilator tester calibration device according to any one of claims 1-9, characterized in that, The exhaust component layer (3) includes a vertical platform (31) and a horizontal platform (32). The detection instrument connection port (311) is installed on the front of the vertical platform (31). The components installed on the front of the vertical platform (31) also include a power socket (312) and a data cable interface (313). An inspection window that can be opened is provided at the horizontal platform (32).

Images