A metal diaphragm capacitance composite vacuum gauge

Abstract

The present invention discloses a metal diaphragm capacitor composite vacuum gauge, which relates to the technical field of vacuum gauges, and includes a vacuum gauge body and a control module, and a lower sealing block is fixedly connected to the lower side of the vacuum gauge body, and a connecting pipe is fixedly connected to the lower side of the lower sealing block, and the connecting pipe is connected to the interior of the vacuum gauge body, and an electrode is fixedly connected to the upper side of the inner wall of the vacuum gauge body, and a capacitor diaphragm is provided on the lower side of the electrode, and the electrode and the capacitor diaphragm are not in contact, and a buffer cavity is opened inside the connecting pipe, and a buffer mechanism is provided inside the buffer cavity, and a detection mechanism is provided on the outside of the connecting pipe. The present invention is provided with a connecting pipe, an airway and a block, which can effectively block the upwelling of high-speed gas when airflow recoil occurs, slow down the instantaneous impact on the capacitor diaphragm, and avoid the diaphragm deformation exceeding the limit to cause reading deviation or device damage. It has the characteristics of strong practicality and improved system adaptability to complex working conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of vacuum gauges, in particular to a metal diaphragm capacitor composite vacuum gauge. Background Art

[0002] A vacuum gauge is a key instrument used to measure gas pressure within confined spaces. It is widely used in vacuum system status monitoring, leak detection, and process control. Capacitive vacuum gauges are widely used in medium and high vacuum measurements due to their sensitive response, high accuracy, and wide applicable pressure range. This type of vacuum gauge typically measures the vacuum indirectly by deforming a metal diaphragm under the influence of a reference pressure and the pressure being measured, with the change in capacitance reflecting the diaphragm displacement.

[0003] However, in some industrial applications, vacuum systems are prone to short-term, intense airflow shocks caused by valve opening and closing, sudden unloading, or backwash from the high-pressure section. This backwash can surge along the pipeline into the vacuum gauge, causing the diaphragm to be overstressed or deformed nonlinearly, leading to measurement errors and even damage to the gauge's delicate internal structure, affecting its service life and measurement stability. Traditional capacitive vacuum gauges lack effective protection against such transient abnormal interference and are often unable to distinguish between normal pressure changes and backwash interference, resulting in inaccurate readings or false alarms, affecting the reliable control of the vacuum system.

[0004] Existing Chinese patent publication number CN114459670A discloses a capacitance film vacuum gauge. The device is provided with an elastic diaphragm and a bracket, with the two ends of the bracket connected to the elastic diaphragm and the sensing diaphragm respectively. This can prevent the center distance of the sensing diaphragm from varying significantly while the outer edge distance varies slightly, thereby ensuring the accuracy and sensitivity of the capacitance film vacuum gauge. However, when the device responds to backflow, the large instantaneous airflow can cause the sensing diaphragm to be impacted, thereby affecting the structural stability and causing reading drift.

[0005] Therefore, there is an urgent need for a composite vacuum gauge structure with the ability to alleviate, protect and assist in the correction of recoil airflow, which can not only achieve physical buffering of airflow interference, but also infer the true reading through structural response and pressure difference information, thereby improving the system's adaptability to complex working conditions and measurement reliability. Summary of the Invention

[0006] The object of the present invention is to provide a metal diaphragm capacitance composite vacuum gauge to solve the problems raised in the above background technology.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: a metal diaphragm capacitance composite vacuum gauge, comprising a vacuum gauge body and a control module, wherein a lower sealing block is fixedly connected to the lower side of the vacuum gauge body, a connecting pipe is fixedly connected to the lower side of the lower sealing block, the connecting pipe is connected to the interior of the vacuum gauge body, an electrode is fixedly connected to the upper side of the inner wall of the vacuum gauge body, a capacitance diaphragm is provided on the lower side of the electrode, the electrode and the capacitance diaphragm are not in contact, a buffer cavity is defined inside the connecting pipe, a buffer mechanism is provided inside the buffer cavity, and a detection mechanism is provided on the outside of the connecting pipe;

[0008] The inner diameter of the buffer cavity is larger than the inner diameter of the connecting tube and the inner diameter of the lower sealing block. The inner volume of the buffer cavity is smaller than the volume of the measured cavity. The lower side of the connecting tube is connected to the lower side of the capacitor diaphragm through the buffer cavity and the inner side of the lower sealing block.

[0009] According to the above technical solution, the buffer mechanism includes a base, the lower surface of the base is fixedly connected to the lower side of the inner wall of the buffer cavity, the upper side of the base is fixedly connected to a spring, the upper end of the spring is fixedly connected to a block, the block is located in the middle of the lower sealing block, the outer wall of the block is in contact with the inner wall of the lower sealing block, and an air passage is opened on the inner side of the block.

[0010] According to the above technical solution, the inner diameter of the upper side of the inner wall of the lower sealing block is smaller than the outer diameter of the block, the air channel and the block form a Tesla-like valve body structure, and the flow blocking direction of the block is from bottom to top.

[0011] According to the above technical solution, the detection mechanism includes a sealing ring, the inner wall of the sealing ring is fixedly connected to the outer wall of the connecting tube, the right side of the sealing ring is connected to a sealing cylinder, the left end of the sealing cylinder passes through the connecting tube and extends to the interior of the buffer chamber, the interior of the sealing cylinder is filled with liquid, the left side of the inner wall of the sealing cylinder is fixedly connected to a sealing ring, the inner wall of the sealing ring is fixedly connected to an elastic metal film, the rear side of the sealing cylinder is fixedly connected to a pressure detection mechanism, and the detection end of the pressure detection mechanism is located inside the sealing cylinder.

[0012] According to the above technical solution, the end of the sealing cylinder located on the outside of the lower sealing block is a conical structure, and the elastic metal film is made of elastic metal material. The pressure detection mechanism is located on the side of the sealing cylinder away from the connecting pipe, and a cooling mechanism is provided on the outside of the sealing cylinder.

[0013] According to the above technical solution, the cooling mechanism includes a liquid pipe, the two ends of the liquid pipe are respectively fixedly connected to the upper side of the outer wall of the sealing cylinder and the lower side of the outer wall of the sealing cylinder, and the interior of the liquid pipe is connected to the interior of the sealing cylinder, the middle part of the liquid pipe is fixedly connected to the lower side of the outer wall of the lower sealing block, and the lower side of the lower sealing block is also fixedly connected to a motor, the output end of the motor is fixedly connected to a turntable, the outer wall of the turntable is hinged with several connecting arms through a torsion spring, and the end of the connecting arm away from the motor is rotatably connected to a pressure wheel through a bearing.

[0014] According to the above technical solution, the distance from the pressure wheel to the outer wall of the turntable is greater than the distance from the outer wall of the turntable to the outer wall of the liquid pipe. The motor can drive the turntable, connecting arm, and pressure wheel to rotate, and the liquid pipe is located on the rotation path of the pressure wheel.

[0015] Compared with the prior art, the present invention has the following beneficial effects: by providing a connecting pipe, an airway, and a block, the present invention can effectively block the upwelling of high-speed gas when airflow backflow occurs, reduce the instantaneous impact on the capacitor diaphragm, and avoid reading deviation or device damage caused by excessive diaphragm deformation;

[0016] By providing a spring and an air channel, it can simultaneously absorb part of the airflow kinetic energy when the recoil airflow pushes the block upward, and release the energy through structural deformation, thereby reducing the structural resonance caused by transient fluctuations of the airflow and the interference to the sensor cavity;

[0017] By providing an elastic metal membrane and a sealing cylinder, the instantaneous air pressure increase caused by the recoil airflow can be converted into a hydraulic pressure change. The hydraulic pressure change rate can be monitored in real time through the pressure detection mechanism to determine whether it is an abnormal airflow event, thereby providing a reference basis for data screening.

[0018] By providing a liquid pipe, a pressure wheel and a motor, the liquid inside the sealing cylinder can be dynamically circulated during the operation of the device, thereby removing the heat generated by the elastic metal membrane due to frequent pressure, avoiding local overheating and performance degradation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0020] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0021] Figure 2 It is a structural schematic diagram of the lower side of the present invention;

[0022] Figure 3 It is a schematic diagram of the internal structure of the present invention;

[0023] Figure 4This is a schematic diagram of the internal structure of the lower sealing block of the present invention;

[0024] Figure 5 It is a structural schematic diagram of the detection mechanism of the present invention;

[0025] Figure 6 This invention Figure 2 Schematic diagram of the enlarged structure of A;

[0026] In the figure: 1. Vacuum gauge body; 2. Lower sealing block; 3. Connecting pipe; 4. Electrode; 5. Capacitor diaphragm; 6. Buffer chamber; 7. Buffer mechanism; 8. Detection mechanism; 701. Base; 702. Spring; 703. Stopper; 704. Airway; 801. Sealing ring; 802. Sealing cylinder; 803. Sealing ring; 804. Elastic metal film; 805. Pressure detection mechanism; 806. Cooling mechanism; 601. Liquid pipe; 602. Motor; 603. Turntable; 604. Connecting arm; 605. Pressure wheel. DETAILED DESCRIPTION

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0028] See also Figure 1-6 The present invention provides a technical solution: a metal diaphragm capacitor composite vacuum gauge, comprising a vacuum gauge body 1 and a control module, and a lower sealing block 2 is fixedly connected to the lower side of the vacuum gauge body 1, a connecting pipe 3 is fixedly connected to the lower side of the lower sealing block 2, the connecting pipe 3 is connected to the interior of the vacuum gauge body 1, an electrode 4 is fixedly connected to the upper side of the inner wall of the vacuum gauge body 1, a capacitor diaphragm 5 is provided on the lower side of the electrode 4, the electrode 4 and the capacitor diaphragm 5 are not in contact, a buffer cavity 6 is opened inside the connecting pipe 3, a buffer mechanism 7 is provided inside the buffer cavity 6, a detection mechanism 8 is provided on the outside of the connecting pipe 3, the inner diameter of the buffer cavity 6 is larger than the inner diameter of the connecting pipe 3 and the inner diameter of the lower sealing block 2, the inner cavity volume of the buffer cavity 6 is smaller than the volume of the measured cavity, and the lower side of the connecting pipe 3 is connected to the lower side of the capacitor diaphragm 5 through the buffer cavity 6 and the inner side of the lower sealing block 2;

[0029] In actual application, the capacitance diaphragm 5 isolates the upper and lower sides of the vacuum gauge body 1 into two chambers, namely the measurement chamber connected to the vacuum system under test and the reference pressure chamber connected to the high vacuum system. During measurement, the space on both sides of the capacitance diaphragm 5 is evacuated to the reference pressure pb using the high vacuum pumping system. At the same time, the measuring bridge circuit is adjusted to balance it, that is, the indicator instrument points to zero. Then the measuring chamber is connected to the vacuum system under test to complete the subsequent detection operation.

[0030] The buffer mechanism 7 includes a base 701, the lower surface of which is fixedly connected to the lower side of the inner wall of the buffer chamber 6, a spring 702 being fixedly connected to the upper side of the base 701, and a stopper 703 being fixedly connected to the upper end of the spring 702. The stopper 703 is located in the middle of the lower sealing block 2, and the outer wall of the stopper 703 contacts the inner wall of the lower sealing block 2. An air passage 704 is opened on the inner side of the stopper 703, and the inner diameter of the upper side of the inner wall of the lower sealing block 2 is smaller than the outer diameter of the stopper 703. The air passage 704 and the stopper 703 form a Tesla valve body structure, and the flow blocking direction of the stopper 703 is from bottom to top.

[0031] During the subsequent testing process, the gas on the upper side of the block 703 can be discharged downward smoothly through the air channel 704. If airflow backflow occurs, the backflow airflow enters the buffer chamber 6 inside the lower block 2 through the connecting pipe 3. When the upflow airflow passes through the block 703, due to the special nonlinear deflection path of the air channel 704 inside the block 703 and the structure with multiple backflow tongues, diversion chambers and rapid flow slots, the fluid in the reverse flow process is continuously disturbed, deflected and interfered with by backflow, resulting in obvious dynamic pressure loss and path blocking effect.

[0032] This increases the upward resistance of the airflow, thereby driving the stopper 703 upward. At the same time, the traction spring 702 deforms and stores energy, reducing the impact vibration of the airflow on the device and the probability of damage to the internal components of the vacuum gauge body 1. The blocked airflow causes the local air pressure inside the buffer chamber 6 to rise relatively instantly, and then balances with the air on the upper side through the air channel 704 to complete subsequent detection, avoiding subsequent abnormal readings caused by the direct impact of the airflow on the capacitor diaphragm 5;

[0033] The detection mechanism 8 includes a sealing ring 801, the inner wall of the sealing ring 801 is fixedly connected to the outer wall of the connecting pipe 3, the right side of the sealing ring 801 is connected to a sealing cylinder 802, the left end of the sealing cylinder 802 passes through the connecting pipe 3 and extends to the interior of the buffer chamber 6, the sealing cylinder 802 is filled with liquid, the left side of the inner wall of the sealing cylinder 802 is fixedly connected to a sealing ring 803, the inner wall of the sealing ring 803 is fixedly connected to an elastic metal film 804, the rear side of the sealing cylinder 802 is fixedly connected to a pressure detection mechanism 805, the detection end of the pressure detection mechanism 805 is located inside the sealing cylinder 802, the end of the sealing cylinder 802 located outside the lower sealing block 2 is a conical structure, and the elastic metal film 804 is made of elastic metal material, the pressure detection mechanism 805 is located on the side of the sealing cylinder 802 away from the connecting pipe 3, and a cooling mechanism 806 is provided on the outside of the sealing cylinder 802;

[0034] When the backflow causes the air pressure inside the buffer chamber 6 to increase, the gas inside the buffer chamber 6 will impact the elastic metal film 804 to deform the elastic metal film 804, thereby causing the pressure of the liquid inside the sealing cylinder 802 to change. Since the air pressure inside the buffer chamber 6 was relatively low before, and since one side of the sealing cylinder 802 is a tapered structure, the deformation of the elastic metal film 804 caused by the increase in the air pressure inside the buffer chamber 6 will make the hydraulic pressure change inside the sealing cylinder 802 more obvious at the pressure detection mechanism 805, so that the pressure detection mechanism 805 detects that the change in the liquid pressure inside the sealing cylinder 802 per unit time exceeds the normal value. Since the pressure detection mechanism 805 is electrically connected to the control module, and the control module is electrically connected to the vacuum gauge body 1, it can be determined as an abnormal time section by the control module, and the reading of the vacuum gauge body 1 at this time is recorded and marked as an abnormal reading, which is convenient for later identification and does not destroy the sealing environment inside the buffer chamber 6;

[0035] When the airflow backflows into the buffer chamber 6, the reading of the pressure detection mechanism 805 changes greatly in a short time, causing the reading of the pressure detection mechanism 805 to increase from , resulting in a pressure difference. The free flow velocity model is driven by the pressure difference to calculate:

[0036]

[0037] in: : The pressure difference before and after the recoil in the buffer chamber, : gas density, : upwelling gas velocity;

[0038] The upwelling velocity of the recoil airflow can be obtained;

[0039] And substitute the recoil airflow upwelling velocity into the local resistance model of the Tesla valve:

[0040]

[0041] in: : The pressure drop caused by the reverse airflow when passing through the Tesla valve, : local resistance coefficient of Tesla valve, : gas density, The speed of the recoil airflow;

[0042] Substitution have to:

[0043]

[0044] The pressure drop caused by the block 703 can be obtained;

[0045] The pressure drop value can then be used to assist in determining the true value of the recoil airflow;

[0046] The cooling mechanism 806 includes a liquid pipe 601, the two ends of the liquid pipe 601 are fixedly connected to the upper side of the outer wall of the sealing cylinder 802 and the lower side of the outer wall of the sealing cylinder 802 respectively, and the interior of the liquid pipe 601 is communicated with the interior of the sealing cylinder 802, the middle part of the liquid pipe 601 is fixedly connected to the lower side of the outer wall of the lower sealing block 2, and the lower side of the lower sealing block 2 is also fixedly connected to the motor 602, the output end of the motor 602 is fixedly connected to the turntable 603, the outer wall of the turntable 603 is hinged with a plurality of connecting arms 604 through a torsion spring, and the end of the connecting arm 604 away from the motor 602 is rotatably connected to the pressure wheel 605 through a bearing, the distance from the pressure wheel 605 to the outer wall of the turntable 603 is greater than the distance from the outer wall of the turntable 603 to the outer wall of the liquid pipe 601, the motor 602 can drive the turntable 603, the connecting arm 604, and the pressure wheel 605 to rotate, and the liquid pipe 601 is located on the rotation path of the pressure wheel 605;

[0047] During the operation of this device, the motor 602 drives the turntable 603, the connecting arm 604 and the pressure wheel 605 to rotate, so that several pressure wheels 605 continuously pass through the middle of the liquid pipe 601. Since the distance from the pressure wheel 605 to the outer wall of the turntable 603 is greater than the distance from the outer wall of the turntable 603 to the outer wall of the liquid pipe 601, the pressure wheel 605 will contact the outer wall of the liquid pipe 601 and squeeze upward, so that the pressure wheel 605 continues to rotate and squeezes the outer wall of the lower sealing block 2 to continuously move the liquid inside the liquid pipe 601, thereby putting the liquid inside the sealing cylinder 802 into a circulating state, so that the heat generated by the frequent deformation of the elastic metal film 804 is carried away by the liquid circulation, thereby avoiding the failure of the elastic metal film 804 due to high temperature, and making the detection of the pressure detection mechanism 805 more accurate.

[0048] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0049] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A metal diaphragm capacitor composite vacuum gauge, comprising a vacuum gauge body (1) and a control module, characterized in that: The lower side of the vacuum gauge body (1) is fixedly connected to a lower sealing block (2), the lower side of the lower sealing block (2) is fixedly connected to a connecting pipe (3), the connecting pipe (3) is connected to the interior of the vacuum gauge body (1), the upper side of the inner wall of the vacuum gauge body (1) is fixedly connected to an electrode (4), the lower side of the electrode (4) is provided with a capacitor diaphragm (5), the electrode (4) and the capacitor diaphragm (5) are not in contact, a buffer cavity (6) is provided inside the connecting pipe (3), a buffer mechanism (7) is provided inside the buffer cavity (6), and a detection mechanism (8) is provided outside the connecting pipe (3); The buffer mechanism (7) comprises a base (701), the lower surface of the base (701) is fixedly connected to the lower side of the inner wall of the buffer cavity (6), the upper side of the base (701) is fixedly connected to a spring (702), the upper end of the spring (702) is fixedly connected to a stopper (703), the stopper (703) is located in the middle of the lower sealing block (2), the outer wall of the stopper (703) is in contact with the inner wall of the lower sealing block (2), and an air passage (704) is provided on the inner side of the stopper (703); The inner diameter of the buffer cavity (6) is larger than the inner diameter of the connecting tube (3) and the inner diameter of the lower sealing block (2); the inner volume of the buffer cavity (6) is smaller than the volume of the measured cavity; the lower side of the connecting tube (3) is connected to the lower side of the capacitor diaphragm (5) through the buffer cavity (6) and the inner side of the lower sealing block (2).

2. The metal diaphragm capacitance composite vacuum gauge according to claim 1, characterized in that: The inner diameter of the upper side of the inner wall of the lower sealing block (2) is smaller than the outer diameter of the stopper (703), the air channel (704) and the stopper (703) form a Tesla-like valve body structure, and the flow blocking direction of the stopper (703) is from bottom to top.

3. The metal diaphragm capacitance composite vacuum gauge according to claim 1, characterized in that: The detection mechanism (8) includes a sealing ring (801), the inner wall of the sealing ring (801) is fixedly connected to the outer wall of the connecting tube (3), the right side of the sealing ring (801) is connected to a sealing cylinder (802), the left end of the sealing cylinder (802) passes through the connecting tube (3) and extends to the inside of the buffer chamber (6), the inside of the sealing cylinder (802) is filled with liquid, the left side of the inner wall of the sealing cylinder (802) is fixedly connected to a sealing ring (803), the inner wall of the sealing ring (803) is fixedly connected to an elastic metal film (804), the rear side of the sealing cylinder (802) is fixedly connected to a pressure detection mechanism (805), and the detection end of the pressure detection mechanism (805) is located inside the sealing cylinder (802).

4. The metal diaphragm capacitance composite vacuum gauge according to claim 3, characterized in that: The end of the sealing cylinder (802) located outside the lower sealing block (2) is a conical structure, and the elastic metal film (804) is made of elastic metal. The pressure detection mechanism (805) is located on the side of the sealing cylinder (802) away from the connecting pipe (3), and a cooling mechanism (806) is provided on the outside of the sealing cylinder (802).

5. The metal diaphragm capacitance composite vacuum gauge according to claim 4, characterized in that: The cooling mechanism (806) includes a liquid pipe (601), the two ends of the liquid pipe (601) are fixedly connected to the upper side of the outer wall of the sealing cylinder (802) and the lower side of the outer wall of the sealing cylinder (802), respectively, and the interior of the liquid pipe (601) is connected to the interior of the sealing cylinder (802), the middle part of the liquid pipe (601) is fixedly connected to the lower side of the outer wall of the lower sealing block (2), and the lower side of the lower sealing block (2) is also fixedly connected to the motor (602), the output end of the motor (602) is fixedly connected to the turntable (603), the outer wall of the turntable (603) is hinged with a plurality of connecting arms (604) through a torsion spring, and the end of the connecting arm (604) away from the motor (602) is rotatably connected to the pressure wheel (605) through a bearing.

6. The metal diaphragm capacitance composite vacuum gauge according to claim 5, characterized in that: The distance between the pressing wheel (605) and the outer wall of the rotating disk (603) is greater than the distance between the outer wall of the rotating disk (603) and the outer wall of the liquid pipe (601); the motor (602) can drive the rotating disk (603), the connecting arm (604), and the pressing wheel (605) to rotate, and the liquid pipe (601) is located on the rotation path of the pressing wheel (605).

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