Electronic differential pressure gauge with local calibration and zeroing function

Abstract

This invention relates to the field of electronic differential pressure gauges, and provides an electronic differential pressure gauge with local calibration and zeroing functions. The gauge includes a body and a base box. The body includes a differential pressure display screen, a differential pressure sensor, a high-pressure interface, a low-pressure interface, a valve one, a valve two, and a microcontroller unit. The high-pressure interface is located at the positive pressure input end of the differential pressure sensor, and the low-pressure interface is located at the negative pressure input end of the differential pressure sensor. The high-pressure interface is connected to an external high-pressure interface via a pipeline. The low-pressure interface is connected to a calibration interface and an external low-pressure connection port via a pipeline. The external high-pressure interface and the external low-pressure connection port are used to connect to the environment under test. Both the calibration interface and the external low-pressure connection port are connected to the negative pressure input end of the differential pressure sensor via valve two. Valve one is connected between the pipelines of the positive and negative pressure input ends of the differential pressure sensor. This invention solves the problems of traditional differential pressure gauges requiring manual disassembly of pipelines, reliance on external equipment, or inability to be quickly operated on-site during calibration and zeroing.

Description

Technical Field

[0001] This invention relates to the field of electronic differential pressure gauge technology, specifically to an electronic differential pressure gauge with local calibration and zeroing functions. Background Technology

[0002] Differential pressure measurement is a key monitoring parameter in cleanrooms, biosafety laboratories, hospital operating rooms, and other controlled environments. Its accuracy is directly related to the safety and compliance of the environment. As the mainstream measuring instrument, the electronic differential pressure gauge senses the pressure difference between the positive and negative pressure ends through a differential pressure sensor, and the data is processed by a microcontroller unit (MCU) and displayed on the screen.

[0003] Existing electronic differential pressure gauges have the following significant drawbacks in practical applications, especially in high-standard clean environments: To ensure measurement accuracy, differential pressure gauges need to be calibrated to zero periodically to eliminate zero-point drift of the sensor. Traditional methods require operators to manually disconnect the external pressure pipeline, short-circuit the positive and negative pressure input terminals of the sensor, or place it under the same pressure environment. This process is not only cumbersome and inefficient, but more importantly, plugging and unplugging pipeline interfaces in a cleanroom environment can easily disrupt the local airflow balance, introduce external contaminants, or cause the diffusion of internal suspended particles. This violates the original intention of maintaining a positive / negative pressure difference in a clean environment to prevent cross-contamination and brings significant operational risks.

[0004] Range calibration of differential pressure gauges is essential to ensure their long-term metrological performance. Current technology typically requires removing the instrument from its installation location and sending it to a professional metrology institution for calibration, or having technicians bring a standard gauge to the site and perform complex pipeline disconnections. Both methods result in long equipment downtime, affecting continuous monitoring; external calibration is costly and time-consuming, while on-site manual calibration requires highly skilled operators and also faces the same risks of contamination and operational errors associated with pipeline disconnections. Summary of the Invention

[0005] The purpose of this invention is to provide an electronic differential pressure gauge with local calibration and zeroing functions, aiming to solve the problems existing in the current electronic differential pressure gauge.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an electronic differential pressure gauge with local calibration and zeroing functions, comprising a gauge body and a base box, wherein the gauge body is installed in the base box, the gauge body includes a differential pressure display screen, a differential pressure sensor and a microcontroller unit, the microcontroller unit is used to receive differential pressure sensor signals, the differential pressure display screen is used to measure and display the pressure difference between the positive pressure chamber and the negative pressure chamber of the sensor, and the gauge body also includes; The high-pressure interface is located at the positive pressure input terminal of the differential pressure sensor; The low-pressure interface is located at the negative pressure input terminal of the differential pressure sensor; The high-pressure interface is connected to an external high-pressure interface via a pipeline; the low-pressure interface is connected to a calibration interface and an external low-pressure connection port via a pipeline. The calibration interface is used to calibrate the differential pressure gauge, and the external high-pressure interface and the external low-pressure connection port are used to connect to the environment to be tested. Valve 2, the calibration interface and the external low-pressure connection port are both connected to the negative pressure input terminal of the differential pressure sensor through valve 2; Valve 1 is connected between the pipelines at the positive pressure input terminal and the negative pressure input terminal of the differential pressure sensor.

[0007] As a further embodiment of the present invention, the first valve is a bypass valve, used to open or block the direct connection between the positive pressure side and the negative pressure side of the differential pressure sensor; the second valve is an isolation valve, which can selectively connect or isolate the external low-pressure connection port and the negative pressure input terminal of the differential pressure sensor by switching its passage state.

[0008] As a further embodiment of the present invention, an automatic sealing valve is provided inside the external low-pressure connection port. The automatic sealing valve includes a sealing cover, a valve core, and an elastic rubber ring. The sealing cover is embedded inside the external low-pressure connection port, the valve core is movably sleeved inside the sealing cover, and the elastic rubber ring is sleeved on the surface of the valve core. The two ends of the sealing cover are connected.

[0009] As a further embodiment of the present invention, the valve core is composed of a plurality of rigid blocks in a ring array, the cross-section of the rigid blocks is fan-shaped, the side of the rigid blocks is provided with grooves, and the elastic rubber ring is sleeved in the grooves.

[0010] As a further embodiment of the present invention, the rigid block is provided with protruding structures at both ends, and the sealing cover is provided with sliding grooves at both ends, with the protruding structures slidably connected in the sliding grooves.

[0011] As a further embodiment of the present invention, one end of the rigid block is provided with a wedge-shaped surface, and the other end of the rigid block is covered with an elastic sealing layer.

[0012] As a further embodiment of the present invention, a connector is provided at one end of the pipeline of the external low-pressure connection port. The connector consists of a conical structure, a threaded structure and a sealing gasket. The conical structure can slide in contact with the wedge-shaped surface of the rigid block and be inserted into the valve core. The threaded structure is threadedly connected to the low-pressure interface, and the sealing gasket is in contact with the end surface of the low-pressure interface.

[0013] As a further embodiment of the present invention, the watch body also includes a communication cable and a mounting hole.

[0014] The beneficial effects of this invention are as follows: By integrating an intelligent valve control system inside the electronic differential pressure gauge, this invention changes the airflow direction through the combined action of internal valves. Thus, without changing the external physical connection, it achieves seamless switching between operating conditions such as "online zeroing" and "normal measurement" through software control. This solves the problems of traditional differential pressure gauges requiring manual disassembly of pipelines, reliance on external equipment, or inability to operate quickly on-site during calibration and zeroing. Attached Figure Description

[0015] Figure 1 This is a perspective view of the surface body in this invention.

[0016] Figure 2 This is a schematic diagram of the installation of the present invention.

[0017] Figure 3 This is a diagram showing the internal structure of valve two in this invention.

[0018] Figure 4 This is a split diagram of the external low-pressure connection port pipe joint and the low-pressure interface of the automatic sealing valve in this invention.

[0019] Figure 5 This is an exploded view of the automatic sealing valve in this invention.

[0020] Figure 6 This is an assembly diagram of the valve core and the elastic rubber ring in this invention.

[0021] Figure 7 This is a planar sectional view of the external low-pressure connection port pipe joint and the low-pressure interface of the automatic sealing valve in this invention.

[0022] Figure 8 For the present invention Figure 7 A magnified view of a portion of point a.

[0023] Figure 9 This is a plan view of the main body of this invention.

[0024] Reference numerals: 100-body, 110-high pressure interface, 120-low pressure interface, 121-automatic sealing valve, 1211-sealing cover, 12111-slide groove, 1212-valve core, 12121-rigid block, 12122-groove, 12123-elastic sealing layer, 12124-protruding structure, 12125-wedge surface, 1213-elastic rubber ring, 130-communication cable, 140-mounting hole, 150-differential pressure display screen; 200-Base box, 300-Calibration interface, 400-External high-pressure interface, 500-Valve 1, 600-Valve 2, 700-External low-pressure connection port, 710-Conical structure, 720-Threaded structure, 730-Sealing gasket. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0026] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0027] Please see Figures 1 to 3 In one embodiment of the present invention, an electronic differential pressure gauge with local calibration and zeroing functions includes a gauge body 100 and a base box. The gauge body 100 is installed in the base box. The gauge body 100 includes a differential pressure display screen 150, a differential pressure sensor, a microcontroller unit, a communication cable 130, and a mounting hole 140. The gauge body 100 also includes; The high-pressure interface 110 is located at the positive pressure input terminal of the differential pressure sensor; The low-pressure interface 120 is located at the negative pressure input terminal of the differential pressure sensor; The high-pressure interface 110 is connected to the external high-pressure interface 400 via a pipeline; the low-pressure interface 120 is connected to the calibration interface 300 and the external low-pressure connection port 700 via a pipeline. The calibration interface 300 is used to calibrate the differential pressure gauge, and the external high-pressure interface 400 and the external low-pressure connection port 700 are used to connect to the environment to be tested or a clean room. Valve 2600, see appendix Figure 2 The calibration interface 300 and the external low-pressure connection port 700 are both connected to the negative pressure input terminal of the differential pressure sensor through the valve 600. The valve 600 is a key component for switching the external low-pressure connection port 700 and the calibration interface 300 on and off. Valve 500 is connected between the pipelines of the positive pressure input terminal and the negative pressure input terminal of the differential pressure sensor. See Appendix. Figure 2 A bypass branch is led out from the pipeline between valve 2600 and the negative pressure end of the sensor, and connected to the high pressure side pipeline through valve 1500. Valve 1500 is used to control the short circuit between the positive pressure chamber and the negative pressure chamber.

[0028] In an embodiment of the present invention, see Figure 3 , Figure 3 In this invention, A (+) represents the external high-pressure connection port, A (-) represents the calibration port, B (-) represents the external low-pressure interface 120, ① represents valve one 500, ② represents valve two 600, "+" represents the positive pressure chamber of the sensor, and "-" represents the negative pressure chamber of the sensor. The control logic and steps of the electronic differential pressure gauge of this invention include: Step 1: Normal Measurement Conditions Valve action: Valve 500 (bypass valve): remains closed, blocking the direct connection between the positive and negative pressure sides of the differential pressure sensor.

[0029] Valve 2 600 (isolation valve): Keeps in the right-hand open state, that is, the external low-pressure interface 120 is connected to the negative pressure side of the differential pressure sensor. Both the bypass valve and the isolation valve are solenoid valves.

[0030] Principle: At this time, the positive pressure chamber of the sensor is connected to the external high pressure, and the negative pressure chamber is connected to the external low pressure. The sensor normally outputs the pressure difference value between the two ends.

[0031] Step Two: Zeroing Condition Valve action: Valve 1500 (bypass valve): Opens, connecting the negative pressure chamber and positive pressure chamber of the sensor.

[0032] Valve 2 600 (isolation valve): Keeps in the left-hand position, blocking the connection between the external low-pressure interface 120 and the negative pressure side of the differential pressure sensor to prevent external pressure fluctuations from interfering.

[0033] Principle: At this time, the negative pressure chamber of the sensor introduces the pressure from the positive pressure side through valve 500, and the external high pressure interface 400 and the calibration interface 300 are connected to the same room. At this time, the pressure is equal everywhere, and there is no risk of contamination from different rooms. Both ends of the sensor are subjected to the same pressure at the same time.

[0034] Result: The physical pressure difference is forcibly set to 0. The microcontroller reads the sensor output value at this time as the "zero drift" for storage and compensation, completing automatic zeroing without manual tube disconnection.

[0035] Step 3: Calibration of Operating Conditions Valve action: Valve 500 (bypass valve): remains closed, blocking the direct connection between the positive and negative pressure sides of the differential pressure sensor.

[0036] Valve 2 600 (isolation valve): Keeps in the left-hand position, blocking the connection between the external low-pressure interface 120 and the negative pressure side of the differential pressure sensor, and connecting the calibration interface 300 and the negative pressure side of the differential pressure sensor.

[0037] Principle: At this time, the external high-pressure interface 400 is connected to the positive pressure side of the differential pressure sensor, and the calibration interface 300 is connected to the negative pressure side of the differential pressure sensor. They are located on the same side, which facilitates calibration. During calibration, it is only necessary to connect the positive and negative pressure gauges of the reference gauge to the external high-pressure interface 400 and the calibration interface 300. There is no need to remove them and send them to a calibration company for measurement and calibration.

[0038] The microcontroller unit, as the core processing system, is responsible for receiving sensor signals, executing control logic, and driving the solenoid valve. The differential pressure display screen 150 is used to measure and display the pressure difference between the positive pressure chamber and the negative pressure chamber of the sensor.

[0039] This invention integrates three operating modes—"normal measurement / zeroing / calibration"—into a traditional electronic differential pressure gauge by equipping it with appropriate solenoid valves and actuators and combining them with optimized piping. It can adjust the internal piping flow according to the required operating conditions, avoiding the complexity of calibration and zeroing in traditional differential pressure gauges, greatly improving calibration and zeroing efficiency, and simultaneously reducing the operational risks of cleanrooms. Please see Figures 4 to 8 In another embodiment of the present invention, an automatic sealing valve 121 is provided inside the external low-pressure connection port 700. The automatic sealing valve 121 includes a sealing cover 1211, a valve core 1212, and an elastic rubber ring 1213. The sealing cover 1211 is embedded in the external low-pressure connection port 700, the valve core 1212 is movably sleeved inside the sealing cover 1211, and the elastic rubber ring 1213 is sleeved on the surface of the valve core 1212. (See attached drawing.) Figure 3 The external low-pressure connection port 700 has a specific structure of a three-way valve, and the two ends of the sealing cover 1211 are connected.

[0040] Please see Figures 5 to 8 Furthermore, the valve core 1212 is composed of several rigid blocks 12121 arranged in a ring array. The rigid block 12121 has a fan-shaped cross-section and a groove 12122 is provided on the side of the rigid block 12121. The elastic rubber ring 1213 is sleeved in the groove 12122, which can prevent the elastic rubber ring 1213 from axially shifting, thereby ensuring the centering and consistency of the clamping force.

[0041] Furthermore, the rigid block 12121 is provided with protruding structures 12124 at both ends, and the sealing cover 1211 is provided with sliding grooves 12111 at both ends. The protruding structures 12124 are slidably connected in the sliding grooves 12111 to ensure the consistency of radial movement of the rigid block 12121.

[0042] Furthermore, one end of the rigid block 12121 is provided with a wedge-shaped surface 12125, and the other end of the rigid block 12121 is covered with an elastic sealing layer 12123, which is a silicone layer or a rubber layer.

[0043] For further details, please refer to the appendix. Figure 4The external low-pressure connection port 700 (with an internal three-way valve structure) has a connector at one end of its pipeline. The connector consists of a conical structure 710, a threaded structure 720, and a sealing gasket 730. The conical structure can slide in contact with the wedge-shaped surface 12125 of the rigid block 12121 and be inserted into the valve core 1212. The threaded structure 720 is threadedly connected to the low-pressure interface 120. The sealing gasket 730 contacts the end surface of the low-pressure interface 120. The sealing gasket 730 first forms a first axial seal with the interface end face. Under the action of the elastic rubber ring 1213, the expanded rigid block 12121 uniformly and forcefully hugs the conical part of the connector from the circumferential direction, forming a second radial seal.

[0044] In this embodiment of the invention, on the high-pressure side: the external high-pressure interface 400 is directly connected to the positive pressure input terminal of the differential pressure sensor; on the low-pressure side: the external low-pressure connection port 700 and the calibration interface 300 are connected to the negative pressure input terminal of the differential pressure sensor through valve 600, which is a key component for switching the external high-pressure interface 400 and the external low-pressure connection port 700 on and off; a bypass branch: a branch is led out from the pipeline between valve 600 and the negative pressure terminal of the sensor, which is connected to the high-pressure side pipeline through valve 500, which is used to control the short circuit between the positive pressure chamber and the negative pressure chamber.

[0045] The external low-pressure connector 700 is used to connect to the environment under test or a cleanroom. (Refer to the attached document.) Figure 1There are two sets of both high-pressure and low-pressure interfaces. In actual use, only one set of high-pressure and low-pressure interfaces is needed. The purpose of keeping two sets is to ensure that the differential pressure gauge can be adjusted to measure the pressure on both sides. Unnecessary interfaces are sealed with bolts. When the connector of the external low-pressure connection port 700 connected to the pipeline is not inserted, the elastic deformation of the elastic rubber ring 1213 drives several rigid blocks 12121 of the annular array to slide and fit together with the slide groove 12111 through the protrusion structure 12124. The elastic sealing layer 12123 at one end of the rigid block 12121 forms a sealing layer to prevent external air from flowing into the internal cavity. When the connector is rotated and inserted, the rotational engagement of the thread structure 720 with the thread groove on the inner wall of the low-pressure interface 120 drives the conical structure 710 to squeeze the wedge-shaped surface 12125 of the rigid block 12121, thereby driving several rigid blocks 12121 of the annular array to slide together through the protrusion structure 12124. 1. The protruding structure 12124 slides away from the slide groove 12111 in a mirror manner until the sealing gasket 730 contacts the end surface of the low-pressure interface 120. The elastic force of the elastic ring 1213 is wrapped around the surface of the conical structure 710 by several rigid blocks 12121 in the annular array. When the connector of the external low-pressure connection port 700 is disassembled, the automatic sealing valve 121 can automatically close. This can prevent external pollutants from entering the sensor through the interface and prevent particulate matter from spreading when the valve is switched. It provides bidirectional sealing protection for the key interface under normal conditions and in dynamic processes, which meets the strict requirements of "zero tolerance" for pollution in clean environments.

[0046] While several embodiments and examples of the present invention have been described for those skilled in the art, these embodiments and examples are provided as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention.

[0047] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An electronic differential pressure gauge with local calibration and zeroing functions, comprising a gauge body (100) and a base box, wherein the gauge body (100) is installed in the base box, the gauge body (100) includes a differential pressure display screen (150), a differential pressure sensor, and a microcontroller unit, wherein the microcontroller unit is used to receive signals from the differential pressure sensor, and the differential pressure display screen (150) is used to measure and display the pressure difference between the positive pressure chamber and the negative pressure chamber of the sensor, characterized in that, The table body (100) also includes; High-pressure interface (110) is located at the positive pressure input terminal of the differential pressure sensor; The low-pressure interface (120) is located at the negative pressure input end of the differential pressure sensor; The high-pressure interface (110) is connected to an external high-pressure interface (400) via a pipeline; the low-pressure interface (120) is connected to a calibration interface (300) and an external low-pressure connection port (700) via a pipeline. The calibration interface (300) is used to calibrate the differential pressure gauge, and the external high-pressure interface (400) and the external low-pressure connection port (700) are used to connect to the environment to be tested. Valve 2 (600), the calibration interface (300) and the external low-pressure connection port (700) are both connected to the negative pressure input terminal of the differential pressure sensor through valve 2 (600); Valve 1 (500) is connected between the pipelines of the positive pressure input terminal and the negative pressure input terminal of the differential pressure sensor.

2. An electronic differential pressure gauge with local calibration and zeroing functions according to claim 1, characterized in that, Valve 1 (500) is a bypass valve used to open or block the direct connection between the positive pressure side and the negative pressure side of the differential pressure sensor; Valve 2 (600) is an isolation valve, which can selectively connect or isolate the external low-pressure connection port (700) and the negative pressure input terminal of the differential pressure sensor by switching its passage state.

3. An electronic differential pressure gauge with local calibration and zeroing functions according to claim 1, characterized in that, An automatic sealing valve (121) is provided inside the external low-pressure connection port (700). The automatic sealing valve (121) includes a sealing cover (1211), a valve core (1212), and an elastic rubber ring (1213). The sealing cover (1211) is embedded in the external low-pressure connection port (700). The valve core (1212) is movably sleeved inside the sealing cover (1211). The elastic rubber ring (1213) is sleeved on the surface of the valve core (1212). The two ends of the sealing cover (1211) are connected.

4. An electronic differential pressure gauge with local calibration and zeroing functions according to claim 3, characterized in that, The valve core (1212) is composed of several rigid blocks (12121) arranged in a ring. The rigid block (12121) has a fan-shaped cross-section and a groove (12122) is provided on the side of the rigid block (12121). The elastic rubber ring (1213) is sleeved in the groove (12122).

5. An electronic differential pressure gauge with local calibration and zeroing functions according to claim 4, characterized in that, The rigid block (12121) has protruding structures (12124) at both ends, and the sealing cover (1211) has sliding grooves (12111) at both ends. The protruding structures (12124) are slidably connected in the sliding grooves (12111).

6. An electronic differential pressure gauge with local calibration and zeroing functions according to claim 5, characterized in that, One end of the rigid block (12121) is provided with a wedge-shaped surface (12125), and the other end of the rigid block (12121) is covered with an elastic sealing layer (12123).

7. An electronic differential pressure gauge with local calibration and zeroing functions according to claim 6, characterized in that, One end of the external low-pressure connection port (700) is provided with a connector, which consists of a conical structure (710), a threaded structure (720), and a sealing gasket (730). The conical structure (710) can slide in contact with the wedge-shaped surface (12125) of the rigid block (12121) and be inserted into the valve core (1212). The threaded structure (720) is threadedly connected to the external low-pressure connection port (700), and the sealing gasket (730) is in contact with the end surface of the external low-pressure connection port (700).

8. An electronic differential pressure gauge with local calibration and zeroing functions according to claim 1, characterized in that, The body (100) also includes a communication cable (130) and a mounting hole (140).

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