Differential pressure transmitter

Abstract

The utility model discloses a differential pressure transmitter which comprises a differential pressure transmitter main body, two side walls of a differential pressure sensor of the differential pressure transmitter main body, which are used for arranging diaphragms, are respectively provided with an inner cavity, and the two diaphragms of the differential pressure transmitter main body are arranged on first cavity walls of the two inner cavities of the differential pressure sensor one by one. The first ends of the two liquid filling channels in the differential pressure sensor are communicated with the two diaphragms one by one; the first cavity wall of the inner cavity is opposite to the cavity opening. According to the scheme, the inner cavities are formed in the two side walls, used for arranging the diaphragm, of the differential pressure sensor, so that the distance between the side walls, used for arranging the diaphragm, of the differential pressure sensor is reduced, the distance between the arranged diaphragm and the diaphragm is reduced, and then the horizontal effective length of the two liquid filling channels is shortened to some extent; therefore, the differential pressure generated by the dead weights of the liquid columns in the two liquid filling channels on the two sides of the sensor chip is correspondingly reduced, and the influence of the change of the mounting position on the differential pressure transmitter is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of differential pressure transmitters, in particular to a differential pressure transmitter. Background Art

[0002] A differential pressure transmitter is a transmitter that measures the difference in pressure between the two ends of a device or pipeline. It first measures the differential pressure value, then detects this change with an integrated electronic circuit, and converts and outputs a standard measurement signal of the corresponding pressure (such as 4-20mA, 4-20mA+HART, 0-5V, etc.). The differential pressure transmitter has two pressure interface ends, which are generally divided into a positive pressure end and a negative pressure end (or a high pressure end and a low pressure end). Under normal circumstances, the pressure at the positive pressure end of the differential pressure transmitter should be greater than the pressure at the negative pressure end. The differential pressure transmitter can be used to measure different measurement quantities such as pressure, differential pressure, liquid level, flow, density, etc.

[0003] Specifically, see Figure 1 The differential pressure transmitter is mainly composed of several parts, such as a differential pressure sensor A01, a fixed clamp plate A02, a bolt assembly A03, an upper shell component A04, and a digital display head module A05; the differential pressure sensor A01 and the fixed clamp plate A02 are connected and assembled together through the bolt assembly A03 to form a differential pressure sensor component (referred to as the sensor component), and two closed pressure chambers (positive pressure chamber H and negative pressure chamber L) are formed between the fixed clamp plates A02 and the differential pressure sensor A01 on both sides; the upper shell component A04 is installed on the upper part of the sensor component, and the digital display head module A05 is installed in the upper shell component A04, and connected to the lead wire of the sensor component to form a complete differential pressure transmitter.

[0004] Among them, see Figure 1 and Figure 2 The working principle of the differential pressure transmitter is as follows: media with different pressures enter the high-pressure chamber H and the low-pressure chamber L on both sides of the sensor component through the fixed clamping plates A02 on both sides of the sensor component, and exert pressure on the diaphragm A011 on both sides of the differential pressure sensor A01; the filling channel A012 inside the differential pressure sensor A01 is filled with liquid (silicone oil). According to Pascal's law, the pressure acting on the diaphragm A011 on both sides of the differential pressure sensor will be transmitted to the upper and lower sides of the sensor chip A013 through the sealing liquid (silicone oil) inside the differential pressure sensor without changing the size, so that a pressure difference is generated on the sensor chip A013, causing the bridge resistance of the Huygens bridge of the sensor chip A013 to change. The resistance change is detected by the integrated circuit, and after processing and conversion by the signal processing module A014, the differential pressure value is displayed on the digital display module A05, and a standard measurement signal output that is proportional to it is formed.

[0005] At present, the principle and structure of domestic differential pressure transmitters are similar, and the performance indicators are also similar. Differential pressure transmitters are now used in more and more industries, and the working conditions are becoming more complex and changeable. For example, differential pressure transmitters are sometimes used in working conditions where the angle of inclination often changes when they are installed, such as multi-degree-of-freedom swing tables, tilt swing test tables, swing amusement equipment, and ships in sailing. Customers have more stringent requirements for the performance indicators of differential pressure transmitters, one of which is that the differential pressure transmitter should be less affected by the installation position.

[0006] However, in existing differential pressure transmitters, such as Figure 2 As shown, the distance between the diaphragms A011 on both sides of the differential pressure sensor A01 is generally about 40 mm; Figure 3 As shown in the figure, when the differential pressure transmitter is placed vertically without connecting to the pressure medium, the diaphragm A011 on both sides of the differential pressure sensor A01 is at the same height, the pressure sensing is also the same, and the digital display module shows 0; Figure 4 As shown in the figure, when the differential pressure transmitter is tilted 90° and placed horizontally, the diaphragm A011 on both sides of the differential pressure sensor A01 will have a height gap of 40mm in the horizontal direction. At this time, the closed filling liquid column (40mm high) inside the differential pressure sensor A01 will produce a pressure difference on both sides of the sensor chip A013 due to its own liquid gravity, which is about 400Pa after conversion. Of course, when the differential pressure transmitter is tilted at a greater angle, the greater the height difference between the diaphragms on both sides, the greater the pressure difference change. In other words, the existing differential pressure transmitter is still greatly affected by the installation position, especially the more inclined the differential pressure transmitter is installed, the greater the impact. Utility Model Content

[0007] In view of this, the utility model provides a differential pressure transmitter, which can reduce the differential pressure generated by the deadweight of the liquid columns in the two liquid-filled channels on both sides of the sensor chip, thereby reducing the impact of the differential pressure transmitter on the installation position change.

[0008] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0009] A differential pressure transmitter comprises a differential pressure transmitter body, wherein the differential pressure sensor of the differential pressure transmitter body is used to set the two side walls of the diaphragm, and both sides have inner cavities, the two diaphragms of the differential pressure transmitter body are set one by one on the first cavity walls of the two inner cavities of the differential pressure sensor, and the first ends of the two liquid-filled channels in the differential pressure sensor are connected one by one with the two diaphragms; wherein the first cavity wall of the inner cavity is distributed relative to the cavity opening.

[0010] Preferably, the first cavity walls of the two inner cavities are symmetrically distributed about a middle position between the two side walls of the differential pressure sensor.

[0011] Preferably, the two liquid filling channels include a first liquid filling channel; wherein the second end of the first liquid filling channel is connected to the upper end of the sensor chip of the differential pressure transmitter body;

[0012] The middle vertical portion of the first liquid-filling channel comprises: a first vertical portion, a horizontal portion, and a second vertical portion which are sequentially connected and arranged;

[0013] The second vertical portion, the diaphragm membrane communicated with the first end of the first liquid-filled channel, and the first vertical portion are sequentially close to a middle position between two side walls of the differential pressure sensor.

[0014] Preferably, the two liquid-filling channels further include a second liquid-filling channel; wherein the second end of the second liquid-filling channel is connected to the lower end of the sensor chip;

[0015] The portion from the second end to the first end of the second liquid filling channel is an L-shaped liquid filling channel, and the vertical portion of the L-shaped liquid filling channel and the second vertical portion are equidistant from the middle position between the two side walls of the differential pressure sensor.

[0016] Preferably, the second end of the first liquid-filling channel and the second end of the second liquid-filling channel are staggered up and down; wherein, the second end of the first liquid-filling channel is located at the middle position between the two side walls of the differential pressure sensor, and the second end of the second liquid-filling channel is located on one side of the middle position between the two side walls of the differential pressure sensor.

[0017] Preferably, the diaphragm membrane communicated with the first end of the second liquid-filling channel and the liquid-filling channel of the second liquid-filling channel are successively close to the middle position between the two side walls of the differential pressure sensor.

[0018] Preferably, the lower part of the differential pressure sensor is a split assembly structure along the first direction, and the lower part of the differential pressure sensor has at least two assembly docking surfaces, one of the two assembly docking surfaces is located between the first cavity wall and the cavity opening of an inner cavity of the differential pressure sensor, and the other assembly docking surface is located between the first cavity wall and the cavity opening of another inner cavity of the differential pressure sensor; wherein the first direction is the relative direction of the two side walls of the differential pressure sensor.

[0019] Preferably, the lower portion of the differential pressure sensor comprises: a first portion, a middle portion and a second portion;

[0020] The two side walls of the middle part along the first direction serve as the assembly docking surfaces respectively; the first part and the second part are respectively arranged on the two side walls of the middle part, the first part is provided with a through first inner cavity, the second part is provided with a through second inner cavity, the two side walls of the middle part are provided with middle inner cavities, the first inner cavity and the second inner cavity are respectively connected with the middle inner cavity to form the inner cavity; the two diaphragm membranes are arranged one by one on the first cavity walls of the two middle inner cavities of the middle part; wherein the first cavity wall of the middle part is distributed relatively to the cavity opening.

[0021] Preferably, the first part and the corresponding side walls of the middle part have a first docking positioning structure that cooperates with each other;

[0022] A second docking and positioning structure that cooperates with each other is provided between the second portion and the corresponding side walls of the middle portion.

[0023] Preferably, the first docking positioning structure and / or the second docking positioning structure comprises: a docking positioning groove and a docking positioning protrusion that cooperate with each other;

[0024] The docking positioning groove is formed on the corresponding side wall of the middle part, and the docking positioning protrusion is arranged on the docking surface of the first part or the second part.

[0025] It can be seen from the above technical solution that the differential pressure transmitter provided by the utility model has inner cavities on both side walls of the differential pressure sensor originally used to set the diaphragm, which reduces the spacing between the side walls of the differential pressure sensor used to set the diaphragm, and reduces the spacing after the diaphragm is set, that is, shortens the horizontal spacing between the sensor chip and the diaphragm, and then shortens the horizontal effective length of the two liquid-filling channels, and reduces the liquid level difference between the two liquid-filling channels, and further reduces the differential pressure generated by the deadweight of the liquid column in the two liquid-filling channels on both sides of the sensor chip, thereby reducing the influence of the differential pressure transmitter on the change of the installation position. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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 or the description of the prior art 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.

[0027] Figure 1 It is a structural schematic diagram of an existing differential pressure transmitter;

[0028] Figure 2It is a structural cross-sectional diagram of a differential pressure sensor of an existing differential pressure transmitter;

[0029] Figure 3 It is a simplified schematic diagram of the structure of the normal placement of the differential pressure sensor of the existing differential pressure transmitter;

[0030] Figure 4 It is a simplified schematic diagram of the structure in which the differential pressure sensor of the existing differential pressure transmitter is placed at a 90° tilt;

[0031] Figure 5 A structural cross-sectional view of a differential pressure sensor of a differential pressure transmitter provided in an embodiment of the utility model;

[0032] Figure 6 A simplified schematic diagram of the structure of a differential pressure sensor of a differential pressure transmitter provided by an embodiment of the utility model when placed normally;

[0033] Figure 7 This is a simplified schematic diagram of the structure in which the differential pressure sensor of the differential pressure transmitter provided in an embodiment of the utility model is placed at a 90° tilt.

[0034] Among them, in the existing differential pressure transmitter, A01 differential pressure sensor, A02 fixing clamp, A03 bolt assembly, A04 case component, A05 digital display head component, H high pressure chamber, L low pressure chamber, A011 diaphragm, A012 filling channel, A013 sensor chip, A014 signal processing module;

[0035] Among them, in the differential pressure transmitter of this scheme, B01 is a differential pressure sensor, B011 is a diaphragm, B012 is a liquid filling channel, B013 is a sensor chip, B015 is an inner cavity, B016 is a first vertical part, B017 is a horizontal part, B018 is a second vertical part, B019 is a vertical part, B020 is a first part, B021 is a middle part, and B022 is a second part. DETAILED DESCRIPTION

[0036] In order to solve the technical problems existing in the above-mentioned background technology, this solution reduces the fluctuation effect of the differential pressure transmitter caused by the change of the installation position to a reasonable and controllable numerical range, such as the change amount is below 100Pa, so that the change value can meet the customer's licensing requirements. The key to solving this technical problem lies in improving the structure of the differential pressure sensor, the core pressure-sensing component of the differential pressure transmitter. Details can be seen in the description below.

[0037] 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.

[0038] The differential pressure transmitter provided in the embodiment of the utility model comprises a differential pressure transmitter body, such as Figure 5 As shown, the differential pressure sensor B01 of the differential pressure transmitter body is used to set the diaphragm B011, and both side walls are provided with inner cavities B015. The two diaphragms B011 of the differential pressure transmitter body are set one by one on the first cavity walls of the two inner cavities B015 of the differential pressure sensor B01, and the first ends of the two liquid-filling channels B012 in the differential pressure sensor B01 are connected one by one with the two diaphragms B011; wherein, the first cavity wall and the cavity opening of the inner cavity B015 are distributed relatively to each other.

[0039] It should be noted that the differential pressure transmitter body can be composed of the differential pressure sensor B01, the fixing clamp, the bolt assembly, the upper case component and the digital display head module. On this basis, the structure of the differential pressure sensor B01 is improved, such as Figure 5 As shown, both side walls (relatively distributed) of the differential pressure sensor B01 originally used to set the diaphragm B011 are provided with inner cavities B015. Of course, the inner cavity B015 on one side of the differential pressure sensor B01 is connected to the high-pressure chamber H, and the inner cavity B015 on the other side is connected to the low-pressure chamber L. The two diaphragms B011 are respectively arranged on the first cavity walls of the two inner cavities B015 of the differential pressure sensor B01, wherein the cavity openings of the inner cavities B015 are distributed on the side walls of the differential pressure sensor B01 originally used to set the diaphragm, so that the distance between the two diaphragms B011 can be smaller than the original distance between the two diaphragms, and The first ends of the two liquid-filling channels B012 in the pressure sensor B01 are connected to the two diaphragm films B011 one by one, so that the effective length of each liquid-filling channel B012 in the horizontal direction can be shortened. In this way, when the differential pressure transmitter is tilted and placed horizontally, the height distance between the two diaphragm films B011 can be reduced, which also reduces the liquid level difference of the two liquid-filling channels B012, and thus the differential pressure generated by the deadweight of the liquid column in the two liquid-filling channels B012 on both sides of the sensor chip B013 is also reduced accordingly, thereby reducing the impact of the differential pressure transmitter on the change of the installation position, and better meeting the customer's use requirements. Of course, the external dimensions of the differential pressure sensor B01 of this differential pressure transmitter are consistent with those of the existing differential pressure sensors, ensuring that the external dimensions of the differential pressure transmitter after assembly are consistent, ensuring that the differential pressure transmitter is easy to install, fix and use, and making the differential pressure transmitter have good versatility and interchangeability.

[0040] Among them, Figure 5 As shown in FIG. 1 , after the internal structure of the differential pressure sensor B01 is cleverly designed as described above, the distance between the diaphragms B011 on both sides of the differential pressure sensor B01 can be greatly reduced to 10 mm. Figure 6 As shown in the figure, when the differential pressure transmitter is placed vertically normally, the heights of the diaphragms B011 on both sides of the differential pressure sensor B01 are consistent, and the digital display of the differential pressure transmitter shows 0; Figure 7 As shown, after the differential pressure transmitter is tilted 90° and placed horizontally (laid down), the height spacing of the diaphragm B011 of the differential pressure sensor B01 can also be greatly reduced, and the differential pressure generated by the deadweight of the liquid column in the two liquid-filled channels B012 on both sides of the sensor chip B013 is also reduced accordingly, thereby greatly reducing the impact of the differential pressure transmitter caused by the change in installation position, which can meet the customer's usage requirements. Of course, this impact can be 1 / 4 of the existing impact.

[0041] That is to say, this scheme can be based on the original differential pressure transmitter, and inner cavities are opened on the two side walls of the differential pressure sensor B01 originally used to set the diaphragm B011, which reduces the spacing of the side wall parts of the differential pressure sensor B01 used to set the diaphragm B011, and reduces the spacing of the diaphragm B011 after setting, that is, shortens the horizontal spacing between the sensor chip B013 and the diaphragm B011, shortens the horizontal effective length of the two liquid filling channels B012, and reduces the liquid level difference of the two liquid filling channels B012, thereby reducing the differential pressure generated by the deadweight of the liquid column in the two liquid filling channels B012 on both sides of the sensor chip B013 accordingly, thereby reducing the influence of the differential pressure transmitter on the change of the installation position, that is, reducing the influence of the deadweight of the filling liquid column on the zero position indication, pressure indication and output signal of the differential pressure transmitter when the installation position changes inclination, and this improvement is particularly effective for differential pressure transmitters with a small measuring range (less than 40kPa).

[0042] Specifically, Figure 5 As shown, the first cavity walls of the two inner cavities B015 are symmetrically distributed about the middle position between the two side walls of the differential pressure sensor B01, so that the two diaphragm membranes B011 are also symmetrically distributed about the middle position between the two side walls of the differential pressure sensor B01, which means that the two diaphragm membranes B011 are still symmetrically distributed on the differential pressure sensor B01, thereby making the distance from the high-pressure chamber H to the diaphragm membrane B011 on its side and the distance from the low-pressure chamber L to the diaphragm membrane B011 on its side tend to be the same, avoiding errors caused by media of different pressures exerting pressure on the diaphragm membranes B011 on both sides of the differential pressure sensor B01, thereby ensuring the measurement accuracy of the differential pressure sensor B01.

[0043] Specifically, Figure 5As shown, the two liquid filling channels B012 include a first liquid filling channel; wherein the second end of the first liquid filling channel is connected to the upper end of the sensor chip B013 of the differential pressure transmitter body;

[0044] like Figure 6 As shown, the middle vertical part of the first liquid-filling channel includes: a first vertical part B016, a horizontal part B017 and a second vertical part B018 which are connected in sequence;

[0045] The second vertical portion B018, the diaphragm membrane B011 communicated with the first end of the first liquid-filling channel, and the first vertical portion B016 are sequentially close to the middle position between the two side walls of the differential pressure sensor B01.

[0046] Among them, Figure 5 As shown, the first liquid filling channel can be the right liquid filling channel inside the differential pressure sensor B01, and its first end is connected to the right diaphragm membrane B011, the second end is connected to the upper end of the sensor chip B013, and the third end is used to fill with liquid; the original middle vertical part of the first liquid filling channel (such as Figure 2 As shown in FIG. 1 , the first vertical part B016, the horizontal part B017 and the second vertical part B018 are connected in sequence. Figure 6 As shown, the second vertical portion B018 is closer to the middle position between the two side walls of the differential pressure sensor B01 than the diaphragm B011 connected to the first end of the first liquid filling channel, and the diaphragm B011 connected to the first end of the first liquid filling channel is closer to the middle position between the two side walls of the differential pressure sensor B01 than the first vertical portion B016; that is, the middle vertical portion of the first liquid filling channel adopts a circuitous arrangement, which can further shorten the horizontal effective length of the first liquid filling channel. Compared with the existing arrangement of the first liquid filling channel, the horizontal effective length of the first liquid filling channel can be greatly shortened, and the liquid level difference between the two liquid filling channels B012 can be further reduced, thereby making the differential pressure generated by the deadweight of the liquid column in the two liquid filling channels B012 on both sides of the sensor chip B013 further reduced accordingly, thereby further reducing the influence of the differential pressure transmitter on the change of the installation position.

[0047] Furthermore, if Figure 5 As shown, the two liquid filling channels B012 further include a second liquid filling channel; wherein the second end of the second liquid filling channel is connected to the lower end of the sensor chip B013;

[0048] like Figure 6 As shown, the portion from the second end to the first end of the second liquid filling channel is an L-shaped liquid filling channel, and the vertical portion B019 and the second vertical portion B018 of the L-shaped liquid filling channel are equidistant from the middle position between the two side walls of the differential pressure sensor B01.

[0049] Among them, Figure 5 As shown, the second liquid filling channel can be the left liquid filling channel inside the differential pressure sensor B01, and its first end is connected to the left diaphragm membrane B011, the second end is connected to the lower end of the sensor chip B013, and the third end is used to fill with liquid; of course, the part from the second end to the first end of the second liquid filling channel is also originally an L-shaped liquid filling channel (such as Figure 2 As shown in the figure, the vertical part B019 and the second vertical part B018 of the L-shaped liquid filling channel are equidistant from the middle position between the two side walls of the differential pressure sensor B01. Compared with the original arrangement position of the second liquid filling channel, this makes it easier for the second end of the first liquid filling channel and the second end of the second liquid filling channel to be staggered in the upper and lower positions on the sensor chip B013, which can further shorten the horizontal effective length of the second liquid filling channel, and further reduce the liquid level difference between the two liquid filling channels B012, thereby further reducing the differential pressure generated by the deadweight of the liquid column in the two liquid filling channels B012 on both sides of the sensor chip B013, thereby further reducing the influence of the installation position change on the differential pressure transmitter.

[0050] Furthermore, as mentioned above, Figure 5 As shown, the second end of the first liquid-filling channel and the second end of the second liquid-filling channel are staggered in the vertical direction; wherein, the second end of the first liquid-filling channel is located in the middle position between the two side walls of the differential pressure sensor B01, and the second end of the second liquid-filling channel is located on one side of the middle position between the two side walls of the differential pressure sensor B01. Of course, this is due to the spacing distribution of the vertical portion B019 of the L-shaped liquid-filling channel and the middle position between the two side walls of the differential pressure sensor B01. In addition, the second end of the first liquid-filling channel can also be located on the other side of the middle position between the two side walls of the differential pressure sensor B01; for example, Figure 5 As shown, the second end of the first liquid-filling channel can be located on the right side of the middle position between the two side walls of the differential pressure sensor B01, and the second end of the second liquid-filling channel can be located on the left side of the middle position between the two side walls of the differential pressure sensor B01.

[0051] In this scheme, if Figure 5 As shown, the diaphragm B011 connected to the first end of the second liquid filling channel and the liquid filling channel of the second liquid filling channel are respectively close to the middle position between the two side walls of the differential pressure sensor B01. Figure 5As shown, the left diaphragm membrane B011 connected to the first end of the left liquid filling channel is closer to the middle position between the two side walls of the differential pressure sensor B01 than the liquid filling channel of the left liquid filling channel, so that the horizontal effective length of the second liquid filling channel can be further shortened. Of course, compared with the existing arrangement of the second liquid filling channel, its horizontal effective length can be greatly shortened, which can further reduce the liquid level difference between the two liquid filling channels B012, and then the differential pressure generated by the deadweight of the liquid column in the two liquid filling channels B012 on both sides of the sensor chip B013 is also further reduced accordingly, so that the influence of the differential pressure transmitter caused by the change of the installation position is further reduced.

[0052] Specifically, Figure 5 As shown, the lower part of the differential pressure sensor B01 is a split assembly structure along the first direction, and the lower part of the differential pressure sensor B01 has at least two assembly docking surfaces, one of the two assembly docking surfaces is located between the first cavity wall and the cavity opening of an inner cavity B015 of the differential pressure sensor B01, and the other assembly docking surface is located between the first cavity wall and the cavity opening of another inner cavity B015 of the differential pressure sensor B01; wherein the first direction is the relative direction of the two side walls of the differential pressure sensor B01.

[0053] Among them, the lower part of the differential pressure sensor B01 can be divided into three parts along the first direction, and an assembly docking surface is provided between each two adjacent parts. In this case, the lower part of the differential pressure sensor B01 has a total of two assembly docking surfaces, one of which is located between the first cavity wall and the cavity opening of an inner cavity of the differential pressure sensor B01, and the other is located between the first cavity wall and the cavity opening of another inner cavity of the differential pressure sensor B01. In this way, the upper diaphragm membrane B011 can be respectively arranged on the first cavity walls of the two inner cavities in the middle part, and then the two side parts are respectively arranged on the two assembly docking surfaces of the middle part, so as to facilitate the two diaphragm membranes B011 to be arranged one by one on the first cavity walls of the two inner cavities B015 of the differential pressure sensor B01, thereby avoiding the situation of insufficient operating space when setting the diaphragm membrane B011.

[0054] Furthermore, if Figure 5 As shown, the lower part of the differential pressure sensor B01 includes: a first part B020, a middle part B021 and a second part B022 along the first direction;

[0055] The two side walls of the middle part B021 along the first direction serve as assembly docking surfaces respectively; the first part B020 and the second part B022 are respectively arranged on the two side walls of the middle part B021, the first part B020 is provided with a through first inner cavity, the second part B022 is provided with a through second inner cavity, and the two side walls of the middle part B021 are both provided with middle inner cavities, and the first inner cavity and the second inner cavity are respectively connected with the middle inner cavity to form an inner cavity B015; two diaphragm membranes B011 are arranged one by one on the first cavity walls of the two middle inner cavities of the middle part B021; wherein, the first cavity wall of the middle part B021 is distributed relatively to the cavity opening.

[0056] It should be noted that if Figure 5 As shown, the two opposite side walls of the middle part B021 along the first direction are respectively used as assembly docking surfaces; the first part B020 and the second part B022 can be respectively welded to the above-mentioned two opposite side walls of the middle part B021; wherein, the two diaphragm sheets B011 can be firstly welded to the first cavity walls of the two middle inner cavities of the middle part B021, and then the first part B020 and the second part B022 can be respectively welded to the two side walls of the middle part B021, so as to complete the arrangement of the two diaphragm sheets B011 at the lower part of the differential pressure sensor B01, thus avoiding the welding tool from extending into the cavity opening of the inner cavity B015 of the differential pressure sensor B01, and facilitating the welding of the diaphragm sheet B011 to the first cavity wall of the middle inner cavity of the middle part B021. In addition, as Figure 5 As shown, the middle part B021 is connected to the upper part of the differential pressure sensor B01, and the middle and lower parts of the two liquid-filling channels B012 are also distributed in the middle part B021. In addition, in order to facilitate the compact installation of the diaphragm B011, the first cavity wall of each middle inner cavity of the middle part B021 can be provided with an installation groove or an installation cavity for matching with the diaphragm B011, and the shape of the installation groove or the installation cavity matches the diaphragm B011.

[0057] Furthermore, in order to facilitate the first part B020 and the second part B022 to dock with the two side walls of the middle part B021, the first part B020 and the corresponding side walls of the middle part B021 are provided with a first docking positioning structure that cooperates with each other;

[0058] A second docking and positioning structure that cooperates with each other is provided between the corresponding side walls of the second portion B022 and the middle portion B021.

[0059] Specifically, Figure 5 As shown, the first docking positioning structure and / or the second docking positioning structure include: a docking positioning groove and a docking positioning protrusion that cooperate with each other; wherein, the docking positioning groove is opened on the corresponding side wall of the middle part B021, and the docking positioning protrusion is arranged on the docking surface of the first part B020 or the second part B022.

[0060] Among them, Figure 5 As shown, the left side wall of the middle part B021 can be provided with a docking positioning groove, and the docking surface of the first part B020 can be provided with a docking positioning protrusion for cooperating with the docking positioning groove of the left side wall of the middle part B021, wherein the docking positioning groove of the left side wall of the middle part B021 can be an annular docking positioning groove surrounding the first direction, and accordingly, the docking positioning protrusion of the docking surface of the first part B020 can also be an annular docking positioning protrusion surrounding the first direction, and cooperate with the annular docking positioning groove of the left side wall of the middle part B021; similarly, the right side wall of the middle part B021 can be provided with a docking positioning groove, and the docking surface of the second part B022 is provided with a docking positioning protrusion for cooperating with the docking positioning groove of the right side wall of the middle part B021, wherein the docking positioning groove of the right side wall of the middle part B021 can be an annular docking positioning groove surrounding the first direction, and accordingly, the docking positioning protrusion of the docking surface of the second part B022 can also be an annular docking positioning protrusion surrounding the first direction, and cooperate with the annular docking positioning groove of the right side wall of the middle part B021. That is to say, the first docking positioning structure and / or the second docking positioning structure can adopt an annular docking positioning convex groove structure, which has the characteristics of simple structure and convenient docking positioning. Of course, the first docking positioning structure and / or the second docking positioning structure can also adopt a docking positioning hole column structure, which will not be repeated here.

[0061] In addition, it should be noted that the improvement method of the internal structure of the differential pressure sensor provided by this scheme is not only applicable to single crystal silicon differential pressure sensors, but also to differential pressure sensors with different measurement principles such as diffused silicon differential pressure sensors and capacitive differential pressure sensors; and the internal filling liquid of this differential pressure transmitter is not limited to silicone oil, but is also applicable to high-temperature silicone oil, low-temperature silicone oil, fluorine oil, and sanitary oil; and this differential pressure transmitter shortens the distance between the sensor chip and the diaphragm, reducing the influence of the deadweight of the filling liquid column on the zero position indication, pressure indication and output signal of the differential pressure transmitter when the installation position changes, which is not only applicable to differential pressure transmitters, but also to pressure transmitters.

[0062] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0063] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A differential pressure transmitter, comprising a differential pressure transmitter body, characterized in that: The differential pressure sensor (B01) of the differential pressure transmitter body is used to set the diaphragm (B011), and both side walls are provided with inner cavities (B015). The two diaphragms (B011) of the differential pressure transmitter body are set one by one on the first cavity walls of the two inner cavities (B015) of the differential pressure sensor (B01), and the first ends of the two liquid-filled channels (B012) in the differential pressure sensor (B01) are connected one by one with the two diaphragms (B011); wherein the first cavity wall of the inner cavity (B015) is distributed relative to the cavity opening.

2. The differential pressure transmitter according to claim 1, characterized in that: The first cavity walls of the two inner cavities (B015) are symmetrically distributed about the middle position between the two side walls of the differential pressure sensor (B01).

3. The differential pressure transmitter according to claim 2, characterized in that: The two liquid filling channels (B012) include a first liquid filling channel; wherein the second end of the first liquid filling channel is connected to the upper end of the sensor chip (B013) of the differential pressure transmitter body; The middle vertical portion of the first liquid-filling channel comprises: a first vertical portion (B016), a horizontal portion (B017) and a second vertical portion (B018) which are sequentially connected; The second vertical portion (B018), the diaphragm membrane (B011) connected to the first end of the first liquid-filled channel, and the first vertical portion (B016) are sequentially close to the middle position between the two side walls of the differential pressure sensor (B01).

4. The differential pressure transmitter according to claim 3, characterized in that: The two liquid-filling channels (B012) further include a second liquid-filling channel; wherein the second end of the second liquid-filling channel is connected to the lower end of the sensor chip (B013); The portion from the second end to the first end of the second liquid-filling channel is an L-shaped liquid-filling channel, and the vertical portion (B019) of the L-shaped liquid-filling channel and the second vertical portion (B018) are equidistant from the middle position between the two side walls of the differential pressure sensor (B01).

5. The differential pressure transmitter according to claim 4, characterized in that: The second end of the first liquid-filling channel and the second end of the second liquid-filling channel are staggered in an upward and downward manner; wherein the second end of the first liquid-filling channel is located at a middle position between the two side walls of the differential pressure sensor (B01), and the second end of the second liquid-filling channel is located on one side of the middle position between the two side walls of the differential pressure sensor (B01).

6. The differential pressure transmitter according to claim 4, characterized in that: The diaphragm membrane (B011) communicated with the first end of the second liquid-filling channel and the liquid-filling channel of the second liquid-filling channel are successively close to the middle position between the two side walls of the differential pressure sensor (B01).

7. The differential pressure transmitter according to claim 1, characterized in that: The lower part of the differential pressure sensor (B01) is a split assembly structure along a first direction, and the lower part of the differential pressure sensor (B01) has at least two assembly docking surfaces, one of the two assembly docking surfaces is located between the first cavity wall and the cavity opening of an inner cavity (B015) of the differential pressure sensor (B01), and the other assembly docking surface is located between the first cavity wall and the cavity opening of another inner cavity (B015) of the differential pressure sensor (B01); wherein the first direction is the relative direction of the two side walls of the differential pressure sensor (B01).

8. The differential pressure transmitter according to claim 7, characterized in that: The lower part of the differential pressure sensor (B01) comprises: a first part (B020), a middle part (B021) and a second part (B022); The two side walls of the middle part (B021) along the first direction serve as the assembly docking surfaces respectively; the first part (B020) and the second part (B022) are respectively arranged on the two side walls of the middle part (B021); the first part (B020) is provided with a through first inner cavity, and the second part (B022) is provided with a through second inner cavity; the two side walls of the middle part (B021) are both provided with middle inner cavities, and the first inner cavity and the second inner cavity are respectively connected with the middle inner cavity to form the inner cavity (B015); the two diaphragm membranes (B011) are arranged one by one on the first cavity walls of the two middle inner cavities of the middle part (B021); wherein the first cavity wall of the middle part (B021) is distributed relative to the cavity opening.

9. The differential pressure transmitter according to claim 8, characterized in that: A first docking and positioning structure that cooperates with each other is provided between corresponding side walls of the first part (B020) and the middle part (B021); A second docking and positioning structure that cooperates with each other is provided between the corresponding side walls of the second part (B022) and the middle part (B021).

10. The differential pressure transmitter according to claim 9, characterized in that: The first docking positioning structure and / or the second docking positioning structure comprises: a docking positioning groove and a docking positioning protrusion that cooperate with each other; The docking positioning groove is provided on the corresponding side wall of the middle part (B021), and the docking positioning protrusion is provided on the docking surface of the first part (B020) or the second part (B022).

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