Glass tube micro differential pressure sensor

Abstract

The utility model discloses a glass tube micro differential pressure sensor, comprising a pressure-resistant cylinder; the glass tube is arranged in the pressure-resistant cylinder, and the upper end and the lower end of the glass tube are sleeved with plugging pieces respectively; a glass piston; the air chamber comprises an upper air chamber and a lower air chamber which are arranged in the pressure-resistant cylinder, the upper end of the glass tube penetrates through the side wall of the upper air chamber and extends into the upper air chamber, the lower end of the glass tube penetrates through the side wall of the lower air chamber and extends into the lower air chamber, a communicating port is formed in the bottom of the lower air chamber, and a self-locking spherical one-way valve is mounted on the communicating port; the buffering assembly and the buffering assembly are installed at the two ends of the glass tube, and the buffering assembly corresponds to the glass piston. A pressure change recording unit; a first pressure guide air hole and a second pressure guide air hole are formed in the side wall of the glass tube. According to the utility model, the glass tube and the glass piston are adopted as differential pressure sensitive elements, so that compared with a differential pressure sensor with an electronic device structure, the structure is simple, the cost is extremely low, and higher differential pressure measurement precision is kept.

Description

Technical Field

[0001] The utility model relates to the technical field of pressure sensors, in particular to a glass tube micro differential pressure sensor. Background Art

[0002] Differential pressure sensors are the most commonly used sensors in the industrial field. They are of various types and have a wide range of applications. However, there are only a handful of sensors that can be used for micro differential pressure measurements. Usually, most domestic sensors are strain gauge pressure sensors, while foreign ones include capacitive and quartz resonant types. Strain gauge and capacitive pressure sensors are widely used because of their low price and ease of use. However, they have many factors such as creep, hysteresis, temperature drift, low repeatability, and complex circuits, which make their measurement accuracy generally around 0.1%, and cannot meet the requirements of high-precision differential pressure tests such as interference pressure and pulse differential pressure tests. For this type of high-precision micro differential pressure test, a quartz resonant pressure sensor is usually used to complete it, but this sensor has a complex structure and is expensive, making it inconvenient to promote.

[0003] Based on the above technical problems, the utility model provides a glass tube micro differential pressure sensor. Utility Model Content

[0004] The utility model aims to provide a glass tube micro differential pressure sensor to solve the problems existing in the prior art.

[0005] To achieve the above purpose, the utility model provides the following solution: The utility model provides a glass tube micro differential pressure sensor, comprising:

[0006] Pressure-resistant cylinder;

[0007] A glass tube, wherein the glass tube is arranged in the pressure-resistant cylinder, and sealing members are respectively sleeved on the upper and lower ends of the glass tube;

[0008] A glass piston, the glass piston being slidably disposed in the glass tube;

[0009] An air chamber, the air chamber comprising an upper air chamber and a lower air chamber arranged in the pressure-resistant cylinder, the upper end of the glass tube passes through the side wall of the upper air chamber and extends into the upper air chamber, the lower end of the glass tube passes through the side wall of the lower air chamber and extends into the lower air chamber, a communication port is opened at the bottom of the lower air chamber, and a self-locking ball-type one-way valve is installed on the communication port;

[0010] A buffer assembly, which is installed at both ends of the glass tube and is arranged corresponding to the glass piston;

[0011] A pressure change recording unit, wherein the pressure change recording unit is mounted on the top of the glass piston;

[0012] Wherein, the side walls of the glass tube are respectively provided with a first pressure-conducting air hole and a second pressure-conducting air hole, the first pressure-conducting air hole is connected to the upper air chamber, the second pressure-conducting air hole is connected to the lower air chamber, and a pressure measuring range is formed between the first pressure-conducting air hole and the second pressure-conducting air hole.

[0013] According to the glass tube micro-differential pressure sensor provided by the utility model, the sealing member includes an upper end cover and a lower end cover, the upper end cover is sleeved on the top end of the glass tube, the lower end cover is sleeved on the bottom end of the glass tube, a first through hole is opened at the center position of the upper end cover, and a second through hole is opened at the center position of the lower end cover.

[0014] According to the glass tube micro-differential pressure sensor provided by the utility model, the buffer assembly includes an upper buffer spring and a lower buffer spring, the upper buffer spring and the lower buffer spring are both located in the glass tube, one end of the upper buffer spring is fixedly connected to the upper end cover, and one end of the lower buffer spring is fixedly connected to the lower end cover.

[0015] According to the glass tube micro-differential pressure sensor provided by the utility model, the distance between the bottom end of the upper buffer spring and the first pressure-conducting air hole is equal to the height of the glass piston, and the distance between the top end of the lower buffer spring and the second pressure-conducting air hole is equal to the height of the glass piston.

[0016] According to the glass tube micro-differential pressure sensor provided by the utility model, the elastic force of the lower buffer spring is not less than the sum of the gravity of the glass piston and the static friction between the glass piston and the glass tube.

[0017] According to the glass tube micro differential pressure sensor provided by the utility model, the pressure change recording unit includes a differential pressure recorder, the differential pressure recorder is installed at the top end of the glass piston, and the differential pressure recorder is arranged corresponding to the first perforation. The utility model discloses the following technical effects:

[0018] When the utility model is working, one end of the lower air chamber is connected to the detection environment through the self-locking ball valve. When the pressure in the detection environment is greater than the pressure in the lower air chamber, the self-locking ball one-way valve opens and self-locks, and the external detection environment is connected to the lower air chamber. The upper air chamber is connected through the first pressure-conducting air hole and the second pressure-conducting air hole on the glass tube. The upper air chamber and the lower air chamber form a pressure-equalizing field with balanced internal and external pressures. The piston is within the pressure measuring range, blocking the first pressure-conducting air hole and the second pressure-conducting air hole. When the external pressure fluctuates, the pressure balance between the upper air chamber and the lower air chamber is broken, and the glass piston in the glass tube is pushed to the end with low pressure. When the pressure change value of the detection environment exceeds the pressure measuring range, the piston reaches one of the ends of the glass tube. At this time, the first pressure-conducting air hole and the second pressure-conducting air hole are connected, and the upper air chamber is connected to the lower air chamber. After the pressure of the upper air chamber and the lower air chamber is balanced, the piston enters the pressure measuring range under the action of the buffer component and the pressure of the two air chambers.

[0019] The utility model adopts a glass tube and a glass piston as differential pressure sensitive elements. Compared with the differential pressure sensor of the electronic device structure, the utility model has a simple structure, a very low cost and maintains a relatively high differential pressure measurement accuracy.

[0020] The setting of the lower air chamber can effectively isolate the sensor from the erosion and pollution of the harsh external detection environment. It is very convenient to use on site and effectively ensures the accuracy of differential pressure measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 This is a structural schematic diagram of the glass tube micro differential pressure sensor of the utility model;

[0023] Figure 2 This is a schematic diagram of the matching relationship between the glass tube and the glass piston (the glass piston is located at the top) of the utility model;

[0024] Figure 3 It is a schematic diagram of the matching relationship between the glass tube and the glass piston (the glass piston is located at the bottom) of the utility model.

[0025] Among them, 1. glass tube; 2. glass piston; 3. first pressure-conducting air hole; 4. second pressure-conducting air hole; 5. first through hole; 6. upper buffer spring; 7. lower buffer spring; 8. second through hole; 9. upper air chamber; 10. lower air chamber; 11. self-locking ball-type one-way valve; 12. upper end cover; 13. lower end cover; 14. differential pressure recorder. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0028] Reference Figure 1-3 The utility model provides a glass tube micro differential pressure sensor, comprising:

[0029] Pressure-resistant cylinder;

[0030] The glass tube 1 is arranged in the pressure-resistant cylinder, and the upper and lower ends of the glass tube 1 are respectively provided with plugging pieces; the glass tube 1 and the glass piston 2 are matched by grinding, which is convenient for processing and reduces the processing difficulty;

[0031] A glass piston 2, which is slidably disposed in the glass tube 1;

[0032] The air chamber comprises an upper air chamber 9 and a lower air chamber 10 which are arranged in the pressure-resistant cylinder. The upper end of the glass tube 1 passes through the side wall of the upper air chamber 9 and extends into the upper air chamber 9. The lower end of the glass tube 1 passes through the side wall of the lower air chamber 10 and extends into the lower air chamber 10. A communication port is opened at the bottom of the lower air chamber 10, and a self-locking ball-type one-way valve 11 is installed on the communication port.

[0033] Buffer components, which are installed at both ends of the glass tube 1 and are arranged correspondingly to the glass piston 2;

[0034] A pressure change recording unit, which is mounted on the top of the glass piston 2;

[0035] Among them, the side walls of the glass tube 1 are respectively provided with a first pressure-conducting air hole 3 and a second pressure-conducting air hole 4, the first pressure-conducting air hole 3 is connected to the upper air chamber 9, and the second pressure-conducting air hole 4 is connected to the lower air chamber 10, and a pressure measuring range is formed between the first pressure-conducting air hole 3 and the second pressure-conducting air hole 4.

[0036] When the utility model is working, one end of the lower air chamber 10 is connected to the detection environment through a self-locking ball valve. When the pressure in the detection environment is greater than the pressure in the lower air chamber 10, the self-locking ball check valve 11 is opened and self-locked, and the external detection environment is connected to the lower air chamber 10. The upper air chamber 9 is connected through the first pressure-conducting air hole 3 and the second pressure-conducting air hole 4 on the glass tube 1. The upper air chamber 9 and the lower air chamber 10 form a pressure-equalizing field with balanced internal and external pressures. The piston is within the pressure measuring range, blocking the first pressure-conducting air hole 3 and the second pressure-conducting air hole 4. When the external pressure fluctuates, the pressure balance between the upper air chamber 9 and the lower air chamber 10 is broken, and the glass piston 2 in the glass tube 1 is pushed to the end with low pressure. When the pressure change value of the detection environment exceeds the pressure measuring range, the piston reaches one of the ends of the glass tube 1. At this time, the first pressure-conducting air hole 3 and the second pressure-conducting air hole 4 are connected, and the upper air chamber 9 is connected to the lower air chamber 10. After the pressure of the upper air chamber 9 and the lower air chamber 10 is balanced, the piston enters the pressure measuring range under the action of the buffer component and the pressure of the two air chambers.

[0037] According to a further optimized solution, the sealing member includes an upper end cover 12 and a lower end cover 13. The upper end cover 12 is sleeved on the top end of the glass tube 1, and the lower end cover 13 is sleeved on the bottom end of the glass tube 1. A first through hole 5 is opened at the center of the upper end cover 12, and a second through hole 8 is opened at the center of the lower end cover 13.

[0038] According to a further optimization scheme, the buffer assembly includes an upper buffer spring 6 and a lower buffer spring 7, both of which are located in the glass tube 1, one end of the upper buffer spring 6 is fixedly connected to the upper end cover 12, and one end of the lower buffer spring 7 is fixedly connected to the lower end cover 13.

[0039] According to a further optimization scheme, the distance between the bottom end of the upper buffer spring 6 and the first pressure-conducting air hole 3 is equal to the height of the glass piston 2 , and the distance between the top end of the lower buffer spring 7 and the second pressure-conducting air hole 4 is equal to the height of the glass piston 2 .

[0040] Further optimization scheme, the elastic force of the lower buffer spring 7 is not less than the sum of the gravity of the glass piston 2 and the static friction between the glass piston 2 and the glass tube 1. At the same time, the elastic force needs to be less than the sum of the gravity of the glass piston 2 and the static friction between the glass piston 2 and the glass tube 1 and the pressure measurement range. The elastic force of the upper buffer spring 6 needs to be less than the sum of the pressure measurement range and the gravity of the glass piston 2 and the static friction between the glass piston 2 and the glass tube 1, and greater than the gravity of the glass piston 2 and the static friction between the glass piston 2 and the glass tube 1.

[0041] According to a further optimized solution, the pressure change recording unit includes a differential pressure recorder 14 , which is mounted on the top of the glass piston 2 , and is disposed corresponding to the first perforation 5 .

[0042] The differential pressure recorder 14 is a conventional technology, and this embodiment does not specifically limit the specific model.

[0043] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0044] The embodiments described above are only descriptions of the preferred methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A glass tube micro differential pressure sensor, characterized in that: include: Pressure-resistant cylinder; A glass tube (1), the glass tube (1) being arranged in the pressure-resistant cylinder, and the upper and lower ends of the glass tube (1) being respectively provided with sealing members; A glass piston (2), the glass piston (2) being slidably disposed in the glass tube (1); An air chamber, the air chamber comprising an upper air chamber (9) and a lower air chamber (10) arranged in the pressure-resistant cylinder, the upper end of the glass tube (1) passes through the side wall of the upper air chamber (9) and extends into the upper air chamber (9), the lower end of the glass tube (1) passes through the side wall of the lower air chamber (10) and extends into the lower air chamber (10), a communication port is opened at the bottom of the lower air chamber (10), and a self-locking ball-type one-way valve (11) is installed on the communication port; A buffer assembly, the buffer assembly being mounted at both ends of the glass tube (1), the buffer assembly being arranged corresponding to the glass piston (2); A pressure change recording unit, wherein the pressure change recording unit is installed on the top of the glass piston (2); The side walls of the glass tube (1) are respectively provided with a first pressure-conducting air hole (3) and a second pressure-conducting air hole (4); the first pressure-conducting air hole (3) is connected to the upper air chamber (9); the second pressure-conducting air hole (4) is connected to the lower air chamber (10); and a pressure measuring range is formed between the first pressure-conducting air hole (3) and the second pressure-conducting air hole (4).

2. A glass tube micro differential pressure sensor according to claim 1, characterized in that: The sealing member comprises an upper end cover (12) and a lower end cover (13); the upper end cover (12) is sleeved on the top end of the glass tube (1); the lower end cover (13) is sleeved on the bottom end of the glass tube (1); a first through hole (5) is opened at the center of the upper end cover (12); and a second through hole (8) is opened at the center of the lower end cover (13).

3. A glass tube micro differential pressure sensor according to claim 2, characterized in that: The buffer assembly comprises an upper buffer spring (6) and a lower buffer spring (7), wherein the upper buffer spring (6) and the lower buffer spring (7) are both located in the glass tube (1), one end of the upper buffer spring (6) is fixedly connected to the upper end cover (12), and one end of the lower buffer spring (7) is fixedly connected to the lower end cover (13).

4. A glass tube micro differential pressure sensor according to claim 3, characterized in that: The distance between the bottom end of the upper buffer spring (6) and the first pressure-conducting air hole (3) is equal to the height of the glass piston (2), and the distance between the top end of the lower buffer spring (7) and the second pressure-conducting air hole (4) is equal to the height of the glass piston (2).

5. The glass tube micro differential pressure sensor according to claim 3, characterized in that: The elastic force of the lower buffer spring (7) is not less than the sum of the gravity of the glass piston (2) and the static friction between the glass piston (2) and the glass tube (1).

6. A glass tube micro differential pressure sensor according to claim 3, characterized in that: The pressure change recording unit comprises a pressure difference recorder (14), the pressure difference recorder (14) is installed on the top end of the glass piston (2), and the pressure difference recorder (14) is arranged corresponding to the first through hole (5).

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