Micro-pressure detection instrument with overpressure protection

Abstract

The invention relates to a micro-pressure detection instrument with overpressure protection, which comprises a connecting base arranged on the micro-pressure detection instrument, a pressure sensing joint is arranged at the bottom of the connecting base, a meter housing is arranged at the top of the connecting base, and a meter core is arranged in the meter housing. The damping device further comprises a corrugated pipe seat, an upper corrugated pipe, an upper end cover, a lower corrugated pipe, a lower end cover, a transmission rod, a fixing screw, an oil plug, damping oil, a limiting groove, an O-shaped sealing ring and an annular convex part. According to the micro-pressure detection instrument with the overpressure protection function, the upper corrugated pipe and the lower corrugated pipe are symmetrically arranged and coaxially and rigidly connected with the transmission rod, impact interference is restrained in cooperation with internal damping oil, high-precision and high-linearity stable micro-pressure detection is achieved, pure mechanical limiting is formed through corrugated pipe seat limiting grooves, a transmission rod annular convex part and an O-shaped sealing ring, and the detection precision is high. The transmission rod is directly locked during overload, excessive deformation of the corrugated pipe is avoided from hardware, instantaneous and reliable overpressure protection is provided, and measurement precision and protection reliability are both considered.

Description

Technical Field

[0001] This invention relates to the field of micro-pressure detection instrument technology, specifically a micro-pressure detection instrument with overpressure protection. Background Technology

[0002] Micro-pressure measuring instruments are key testing equipment in fields such as industrial automation, medical equipment, environmental monitoring, HVAC, and precision fluid control. They are mainly used for precise measurement, condition monitoring, and process control in extremely low pressure ranges, playing an important role in ensuring stable system operation and improving control accuracy. These instruments typically consist of a sensing element, a transmission mechanism, a signal conversion module, and a display unit. Their core sensing components often adopt thin elastic diaphragms or bellows structures, specifically designed for micro-pressure measurement scenarios, and feature high sensitivity, good response characteristics, and high measurement accuracy.

[0003] In the current technology, micro-pressure detection instruments rely on thin diaphragms or bellows to generate controllable elastic deformation under micro-pressure. The pressure signal is converted through the correspondence between the deformation displacement and the measured pressure, thereby completing the detection and output of micro-pressure signals, which can meet the high-precision measurement requirements under low-pressure conditions. In practical use, when the system experiences instantaneous pressure shocks, unidirectional static pressure overloads, or on-site misoperations, the micro-pressure sensitive element is prone to exceeding its elastic limit, causing permanent deformation or even rupture of the diaphragm or bellows. This leads to instrument measurement failure, loss of accuracy, or even complete damage. Moreover, existing external pressure relief valves have a delayed response and cannot cope with microsecond-level shocks, simple mechanical limits are prone to damaging the diaphragm and compressing the linear range, and electronic protection relies on circuit reliability and cannot provide ultimate hardware-level protection. Existing structures generally cannot simultaneously achieve both micro-pressure measurement accuracy and high overload protection capabilities. Therefore, a micro-pressure detection instrument with overpressure protection is proposed to solve the above problems. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a micro-pressure detection instrument with overpressure protection. It possesses the advantages of high-precision measurement and overpressure protection, solving the problem that in the event of instantaneous pressure shocks, unidirectional static pressure overloads, or on-site misoperations, the micro-pressure sensitive element is easily overstretched, leading to permanent deformation or even rupture of the diaphragm or bellows, resulting in instrument measurement failure, loss of accuracy, or even complete damage. Furthermore, existing external pressure relief valves have lag in response and cannot cope with microsecond-level shocks, simple mechanical limiting is prone to damaging the diaphragm and compressing the linear range, and electronic protection relies on circuit reliability and cannot provide ultimate hardware-level protection. Existing structures generally cannot simultaneously achieve both micro-pressure measurement accuracy and high overload protection capabilities.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a micro-pressure detection instrument with overpressure protection, comprising a connecting base disposed on the micro-pressure detection instrument, a pressure sensing connector being provided at the bottom of the connecting base, a watch cover being provided at the top of the connecting base, and a watch core being provided inside the watch cover; A bellows seat is fixedly installed on the connecting base, and the top of the bellows seat is fixedly connected to the watch case. An upper bellows is fixedly connected to the top of the bellows seat, and the upper bellows is located inside the watch case. An upper end cap is fixedly connected to the top of the upper bellows. The bottom of the connecting base is fixedly connected to a lower corrugated pipe located inside the pressure-sensing connector, and the bottom of the lower corrugated pipe is fixedly connected to a lower end cap.

[0006] Furthermore, a transmission rod is slidably installed at the center of the corrugated pipe seat, and the two ends of the transmission rod pass through the interior of the lower corrugated pipe and the upper corrugated pipe respectively. Fixing screws are installed on both the lower end cover and the upper end cover, and the two fixing screws are threadedly connected to the two ends of the transmission rod respectively.

[0007] Furthermore, the connecting base is provided with an oil plug, and the interiors of both the lower and upper bellows are filled with damping oil.

[0008] Furthermore, a limiting groove is provided at the bottom of the bellows seat, and an O-ring is provided inside the limiting groove. An annular protrusion is provided on the transmission rod, and the annular protrusion and the transmission rod are an integral structure. The annular protrusion is located inside the limiting groove.

[0009] Furthermore, the distance between the inner top wall of the limiting groove and the bottom of the bellows seat is 5-7mm.

[0010] Compared with the prior art, the present invention provides a micro-pressure detection instrument with overpressure protection, which has the following beneficial effects: 1. This micro-pressure detection instrument with overpressure protection uses an upper and lower bellows arranged symmetrically, a transmission rod that slides coaxially, and a rigid, gapless connection at both ends achieved by fixing screws. This makes the pressure-displacement transmission smoother and the linear relationship more stable. At the same time, the upper and lower bellows are filled with damping oil, which can suppress vibration and impact interference, thereby achieving high-precision, low-hysteresis, and high-linearity micro-pressure detection. 2. This micro-pressure detection instrument with overpressure protection forms a purely mechanical limiting structure through the limiting groove on the bellows seat, the annular protrusion on the transmission rod, and the O-ring seal. In case of overload, the annular protrusion and the limiting groove lock directly, forcibly limiting the axial travel of the transmission rod and preventing excessive compression and deformation of the upper and lower bellows. It can achieve instantaneous and reliable hardware-level protection without relying on circuits and external pressure relief valves. 3. This micro-pressure measuring instrument with overpressure protection precisely limits the maximum displacement stroke by setting the distance between the top wall of the limiting groove and the bottom of the bellows seat to millimeters. This ensures sufficient normal measurement range without affecting micro-pressure accuracy, and can quickly trigger protection in case of overload. The overall structure is integrated with the connecting base, and the symmetrical bellows, coaxial transmission, built-in damping and mechanical limit work together to greatly improve the instrument's impact resistance and off-center load resistance, and extend its service life under complex working conditions. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the structure of the present invention. Figure 1 A sectional view.

[0012] In the diagram: 100, connecting base; 101, oil plug; 102, bellows seat; 103, upper bellows; 104, damping oil; 105, upper end cover; 106, watch case; 107, watch movement; 108, fixing screw; 109, transmission rod; 1091, annular protrusion; 110, O-ring seal; 111, lower bellows; 112, lower end cover; 113, pressure sensing connector; 114, limiting groove. Detailed Implementation

[0013] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0014] Example 1: Please refer to Figures 1-2 In this embodiment, a micro-pressure detection instrument with overpressure protection includes a connecting base 100 disposed on the micro-pressure detection instrument, a pressure sensing connector 113 provided at the bottom of the connecting base 100, a watch cover 106 provided at the top of the connecting base 100, and a watch core 107 provided inside the watch cover 106.

[0015] Example 2: Please refer to Figures 1-2 Based on Embodiment 1, a micro-pressure detection instrument with overpressure protection is provided. A bellows seat 102 is fixedly installed on the connecting base 100, and the top of the bellows seat 102 is fixedly connected to the instrument cover 106. An upper bellows 103 is fixedly connected to the top of the bellows seat 102, and the upper bellows 103 is located inside the instrument cover 106. An upper end cap 105 is fixedly connected to the top of the upper bellows 103. The bottom of the connecting base 100 is fixedly connected to a lower bellows 111 located inside the pressure-sensing connector 113, and the bottom of the lower bellows 111 is fixedly connected to a lower end cap 112.

[0016] It should be noted that the connecting base 100 integrates the pressure sensing connector 113 and the bellows seat 102. The upper bellows 103 and the lower bellows 111 are arranged symmetrically, forming a closed elastic structure through the upper end cover 105 and the lower end cover 112 respectively. This achieves symmetrical force distribution, improves transmission stability and measurement linearity, and provides basic structural support for high-precision micro-pressure measurement and bidirectional overpressure protection. It solves the problem of easy unilateral load distribution and poor stability of the sensitive element of traditional micro-pressure instruments.

[0017] A transmission rod 109 is slidably installed at the center of the bellows seat 102, and the two ends of the transmission rod 109 pass through the interior of the lower bellows 111 and the upper bellows 103, respectively. Fixing screws 108 are installed on the lower end cover 112 and the upper end cover 105, and the two fixing screws 108 are threaded to the two ends of the transmission rod 109, respectively.

[0018] It should be noted that the transmission rod 109 is slidably installed in the center of the bellows seat 102, and its two ends are rigidly connected to the lower end cover 112 and the upper end cover 105 respectively by fixing screws 108. This ensures that the pressure and displacement transmission are coaxial, without gaps or hysteresis, improves the measurement accuracy and response consistency, ensures the signal is stable and reliable, and solves the problems of large displacement transmission gaps, unstable transmission, and poor linearity.

[0019] In addition, a limiting groove 114 is provided at the bottom of the bellows seat 102, and an O-ring 110 is provided inside the limiting groove 114. An annular protrusion 1091 is provided on the transmission rod 109, and the annular protrusion 1091 and the transmission rod 109 are an integral structure. The annular protrusion 1091 is located inside the limiting groove 114.

[0020] It should be noted that a limiting groove 114 is provided at the bottom of the bellows seat 102, and the integrated annular protrusion 1091 of the transmission rod 109 is placed in the limiting groove 114. Together with the O-ring seal 110, it achieves limiting and buffering. When overpressure occurs, the annular protrusion 1091 and the limiting groove 114 are mechanically locked, forcibly stopping the transmission rod 109 and physically cutting off the overload transmission path. The O-ring seal 110 buffers and reduces the impact, protecting the core components from damage. This solves the problems of excessive deformation, easy breakage, and lack of ultimate hardware protection of the diaphragm or bellows when overloaded.

[0021] In addition, the distance between the inner top wall of the limiting groove 114 and the bottom of the bellows seat 102 is 5-7mm.

[0022] It should be noted that precisely limiting the maximum allowable displacement ensures that the normal micro-pressure measurement range is sufficient, while also ensuring rapid triggering of protection in case of overload. This balances measurement accuracy and protection reliability, and solves the problem of premature or failed protection caused by unreasonable limit travel.

[0023] Finally, the connecting base 100 is provided with an oil plug 101, and the interiors of the lower bellows 111 and the upper bellows 103 are both filled with damping oil 104.

[0024] It should be noted that damping oil 104 is used to provide buffer damping, suppress shock and vibration, and improve the instrument's anti-interference ability and operational stability.

[0025] The working principle of the above embodiments is as follows: When this micro-pressure detection instrument with overpressure protection is in use, the pressure of the medium being measured enters through the pressure sensing connector 113 and acts on the lower end cover 112. The pressure pushes the lower end cover 112 to move upward, causing the lower bellows 111 to undergo axial compression elastic deformation. The lower bellows 111 pushes the transmission rod 109 to slide upward along the center of the bellows seat 102 through the bottom fixing screw 108. The top of the transmission rod 109 pushes the upper end cover 105 through the fixing screw 108, so that the upper bellows 103 will generate elastic deformation simultaneously. The axial displacement of the transmission rod 109 is directly transmitted to the dial core 107. The dial core 107 converts the displacement signal into a pressure reading, and completes the display and signal output within the dial housing 106, thereby achieving precise measurement of micro-pressure. When the pressure is too high or a momentary impact occurs, the compression of the lower bellows 111 and the upper bellows 103 increases, and the axial displacement of the transmission rod 109 exceeds the normal measurement range. When the displacement reaches the limit position, the annular protrusion 1091 on the transmission rod 109 comes into contact with the limiting groove 114 in the bellows seat 102. The annular protrusion 1091 is mechanically locked by the limiting groove 114, preventing the transmission rod 109 from continuing axial movement. This forcibly limits the maximum deformation of the lower bellows 111 and the upper bellows 103. At the same time, the O-ring seal 110 provides buffering to avoid rigid impact and completely prevents overload pressure from being transmitted to the movement 107, achieving hardware-level overpressure protection. Furthermore, the annular protrusion 1091, in conjunction with the O-ring seal 110, inside the limiting groove 114, achieves double sealing of the gap between the bellows seat 102 and the transmission rod 109, forming a sealed space inside the lower bellows 111. The plug 101 is used to inject and seal the damping oil 104, which fills the interior of the upper bellows 103 and the lower bellows 111. When pressure fluctuates or there is a sudden impact, the damping oil 104 generates a damping force, which slows down the movement speed of the transmission rod 109 and reduces the impact load on the bellows and the movement 107.

[0026] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0027] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A micro-pressure detection instrument with overpressure protection, comprising a connecting base (100) disposed on the micro-pressure detection instrument, characterized in that: The bottom of the connecting base (100) is provided with a pressure-sensing connector (113), the top of the connecting base (100) is provided with a watch cover (106), and the watch cover (106) is provided with a watch movement (107). A bellows seat (102) is fixedly installed on the connecting base (100), and the top of the bellows seat (102) is fixedly connected to the watch case (106). An upper bellows (103) is fixedly connected to the top of the bellows seat (102), and the upper bellows (103) is located inside the watch case (106). An upper end cap (105) is fixedly connected to the top of the upper bellows (103). The bottom of the connecting base (100) is fixedly connected to a lower corrugated pipe (111) located inside the pressure sensing connector (113), and the bottom of the lower corrugated pipe (111) is fixedly connected to a lower end cap (112).

2. The micro-pressure detection instrument with overpressure protection according to claim 1, characterized in that: A transmission rod (109) is slidably installed at the center of the corrugated pipe seat (102), and the two ends of the transmission rod (109) pass through the interior of the lower corrugated pipe (111) and the upper corrugated pipe (103) respectively. Fixing screws (108) are installed on the lower end cover (112) and the upper end cover (105), and the two fixing screws (108) are threadedly connected to the two ends of the transmission rod (109) respectively.

3. A micro-pressure detection instrument with overpressure protection according to claim 1, characterized in that: The connecting base (100) is provided with an oil plug (101), and the interiors of the lower bellows (111) and the upper bellows (103) are filled with damping oil (104).

4. A micro-pressure detection instrument with overpressure protection according to claim 2, characterized in that: The bottom of the bellows seat (102) is provided with a limiting groove (114), and an O-ring (110) is provided inside the limiting groove (114). The transmission rod (109) is provided with an annular protrusion (1091), and the annular protrusion (1091) and the transmission rod (109) are an integral structure. The annular protrusion (1091) is located inside the limiting groove (114).

5. A micro-pressure detection instrument with overpressure protection according to claim 4, characterized in that: The distance between the inner top wall of the limiting groove (114) and the bottom of the bellows seat (102) is 5-7mm.

Images