Low vacuum pressure transmitter

Abstract

The utility model provides a low vacuum pressure transmitter which comprises a shell base, a sleeve and a cover body, the sleeve is installed at one end of the base, the cover body is installed at one end of the sleeve, and a ceramic capacitance sensor, a circuit board support and a transmitter circuit board are installed in a cavity formed by the base, the sleeve and the cover body. The transmitter circuit board is connected with the ceramic capacitance sensor through a wire, a signal output port of the transmitter circuit board is connected with a 15Pin / D-Sub connector located outside the cover body through a shielding wire, a detection channel is arranged in the shell base, and the detection channel is communicated with the position of the ceramic capacitance sensor. The pressure transmitter adopts the ceramic capacitance sensor, so that the product precision and stability can be ensured, and the transmitter is convenient in overall structural design and installation, low in cost and convenient to popularize and apply.

Description

Technical Field

[0001] The utility model mainly relates to the technical field related to sensors, in particular to a low vacuum pressure transmitter. Background Art

[0002] At present, most of the vacuum pressure transmitters commonly used in photovoltaic, semiconductor and industrial markets have complicated installation processes, and the lines are easily affected by highly corrosive environments during use. The output signal stability is poor and is significantly affected by the environment. Although there are some low vacuum pressure transmitters on the market that claim to have strong anti-interference, good long-term stability and high precision, the range is mostly MPa level and cannot achieve accurate low vacuum measurement. Even if there are Pa-level low vacuum transmitters, they are generally expensive. Utility Model Content

[0003] In order to solve the shortcomings of current technology, the utility model combines the existing technology and provides a low vacuum pressure transmitter based on practical application. The pressure transmitter adopts a ceramic capacitor sensor to ensure product accuracy and stability, and the overall structural design of the transmitter is easy to install and low in cost, which is easy to promote and apply.

[0004] The technical solution of the utility model is as follows:

[0005] A low vacuum pressure transmitter comprises a shell base, a sleeve and a cover body, wherein the sleeve is installed at one end of the base, and the cover body is installed at one end of the sleeve. A ceramic capacitor sensor, a circuit board bracket and a transmitter circuit board are installed in a cavity formed by the base, the sleeve and the cover body. The transmitter circuit board is connected to the ceramic capacitor sensor through a wire, and a signal output port of the transmitter circuit board is connected to a 15Pin / D-Sub connector located outside the cover body through a shielded wire. A detection channel is arranged in the shell base, and the detection channel is connected to the position of the ceramic capacitor sensor.

[0006] Furthermore, a mounting platform is provided at the outer end of the shell base, and an inwardly recessed card slot is provided in the middle of the mounting platform, and the card slot is connected to the detection channel.

[0007] Furthermore, the sleeve is sleeved on the step of the outer ring of the inner end of the shell base, and the sleeve and the shell base, as well as the cover and the sleeve are all connected by welding.

[0008] Furthermore, a mounting groove is provided on the inner end surface of the shell base, the ceramic capacitor sensor is installed in the mounting groove through a gasket, the circuit board bracket is threadedly matched with the mounting groove, the circuit board bracket is pressed against the ceramic capacitor sensor, and the transmitter circuit board is installed on one side of the circuit board bracket.

[0009] Furthermore, the cover body is provided with a through hole for the shielding wire to pass through, and a wire locking ring is provided at the through hole.

[0010] Furthermore, the transmitter circuit board outputs a signal of 4-20mA.

[0011] Furthermore, the shell base, sleeve and cover are all made of stainless steel.

[0012] Beneficial effects of the utility model:

[0013] 1. This product adopts ceramic capacitance sensor, which ensures high precision and high stability of measurement. Its overall structure layout is reasonable, and its sealing performance, corrosion resistance and anti-interference performance are excellent. The processing and production cost is low, which is easy to promote and apply.

[0014] 2. The base of this product adopts a flat card-mounted structural design, which is more convenient for direct installation and testing at the production site than the traditional threaded tightening installation method.

[0015] 3. This product is equipped with a professional 15-pin / D-Sub connector. The 15-pin / D-Sub connector is connected to the transmitter using a shielded wire. The outer layer of the shielded wire ensures the service life of the test circuit for more accurate testing.

[0016] 4. The overall design of this product is smooth, not easy to accumulate oil and dirt and easy to clean. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Attached Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0018] Attached Figure 2 It is a partial structural schematic diagram of the utility model.

[0019] Attached Figure 3 This is a diagram of the 15-pin / D-Sub connector port.

[0020] Numbers shown in the figure: 1. Shell base; 2. Sleeve; 3. Cover; 4. Wire locking ring; 5. Shielding wire; 6. 15Pin / D-Sub connector; 7. Ceramic capacitor sensor; 8. Circuit board bracket; 9. Transmitter circuit board; 10. Gasket; 11. Detection channel; 12. Mounting table; 13. Card slot. DETAILED DESCRIPTION

[0021] The utility model is further described in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the utility model and are not used to limit the scope of the utility model. In addition, it should be understood that after reading the content taught by the utility model, those skilled in the art can make various changes or modifications to the utility model, and these equivalent forms also fall within the scope defined by this application.

[0022] refer to Figure 1 , Figure 2 as well as Figure 3 As shown, it is a schematic diagram of the relevant structure of a low vacuum pressure transmitter provided in this embodiment.

[0023] This transmitter is a high-precision ceramic capacitive sensor vacuum pressure transmitter that can measure in harsh semiconductor and industrial low vacuum and corrosive gas and liquid environments.

[0024] This transmitter is a fully welded structure assembled with a ceramic capacitor pressure sensor, and the structure mainly consists of the following parts: ceramic capacitor sensor 7, stainless steel housing, transmitter circuit board 9, circuit board bracket 8, shielding wire 5, 15Pin / D-Sub connector 6.

[0025] As shown in the figure, the stainless steel shell mainly includes a shell base 1, a sleeve 2 and a cover 3, which are welded together to form a cavity inside the stainless steel shell for installing components such as sensors. As shown in the reference figure, the sleeve 2 is welded to one end of the shell base 1, and the cover 3 is welded to one end of the sleeve 2, wherein a step is set on the outer ring of the inner end of the shell base 1, and the sleeve 2 is sleeved on the outer ring of the shell base 1 and welded to ensure the sealing performance and structural firmness.

[0026] In this embodiment, a mounting groove is provided on the inner end surface of the housing base 1, and the ceramic capacitor sensor 7 and the gasket 10 are installed in the mounting groove. The circuit board bracket 8 is provided on one side of the ceramic capacitor sensor 7, which is installed on the mounting groove through threads and pressed on the ceramic capacitor sensor 7, and 504 glue is applied on the threaded connection.

[0027] The output of the transmitter circuit board 9 is 4-20mA, which is connected to the signal port of the ceramic capacitor sensor 7 with a high-temperature wire. One end of the shielded wire 5 is stripped and soldered to the signal output port of the transmitter circuit board 9; the other end of the shielded wire 5 is stripped and passed through the cover hole on the cover body 3, fixed with the locking wire ring 4 and connected to the 15Pin / D-Sub connector 6. The interface definition of the 15Pin / D-Sub connector 6 is shown in Table 1 below. Using a professional 15Pin / D-Sub connector, the line test is more accurate and ensures the service life of the test line.

[0028] Table 1

[0029] .

[0030] In this embodiment, the installation of the transmitter is achieved by setting a mounting platform 12 at the outer end of the shell base 1, wherein an inwardly recessed slot 13 is set in the middle position of the mounting platform 12, the slot 13 is connected to the detection channel 11, and the detection channel 11 is connected to the position of the ceramic capacitor sensor 7.

[0031] Different from silicon resistance pressure sensor, the low vacuum pressure transmitter of this embodiment is designed to use ceramic capacitance pressure sensor. There is no transmission of liquid medium. The process pressure acts directly on the front surface of the ceramic diaphragm through the detection channel 11. The capacitance change ratio between the substrate electrode and the diaphragm electrode and the pressure magnitude causes the diaphragm to displace, thereby generating a pressure signal. The measurement range of this pressure transmitter is 0-2666Pa, and the accuracy meets <0.5%FS (@25℃), which truly achieves low vacuum, high precision and high cost performance.

Claims

1. A low vacuum pressure transmitter, characterized in that: It includes a shell base, a sleeve and a cover body, the sleeve is installed at one end of the base, the cover body is installed at one end of the sleeve, a ceramic capacitor sensor, a circuit board bracket and a transmitter circuit board are installed in the cavity formed by the base, the sleeve and the cover body, the transmitter circuit board is connected to the ceramic capacitor sensor through a wire, the signal output port of the transmitter circuit board is connected to the 15Pin / D-Sub connector located outside the cover body through a shielded wire, and a detection channel is arranged in the shell base, and the detection channel is connected to the position of the ceramic capacitor sensor.

2. The low vacuum pressure transmitter according to claim 1, characterized in that: A mounting platform is arranged at the outer end of the shell base, and an inwardly recessed card slot is arranged in the middle of the mounting platform, and the card slot is communicated with the detection channel.

3. The low vacuum pressure transmitter according to claim 1, characterized in that: The sleeve is sleeved on the step of the outer circle of the inner end of the shell base, and the sleeve and the shell base, as well as the cover and the sleeve are all connected by welding.

4. The low vacuum pressure transmitter according to claim 1, characterized in that: An installation groove is arranged on the inner end surface of the shell base, the ceramic capacitor sensor is installed in the installation groove through a gasket, the circuit board bracket is threadedly matched with the installation groove, the circuit board bracket is pressed against the ceramic capacitor sensor, and the transmitter circuit board is installed on one side of the circuit board bracket.

5. The low vacuum pressure transmitter according to claim 1, characterized in that: The cover body is provided with a through hole for the shielding wire to pass through, and a wire locking ring is provided at the through hole.

6. The low vacuum pressure transmitter according to claim 1, characterized in that: The output signal of the transmitter circuit board is 4-20mA.

7. The low vacuum pressure transmitter according to claim 1, characterized in that: The shell base, sleeve and cover are all made of stainless steel.

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