CN-122029414-A - Pressure transducer for transmitting the pressure of a process medium

Abstract

The invention relates to a pressure transducer (1) for transmitting pressure of a process medium, comprising a metal body (2), a pressure sensor module (5) comprising a ceramic insulating body (6) and a pressure sensor (7), an isolation diaphragm (8) to which the process medium can be applied from a first isolation diaphragm face (8.1), wherein in the ceramic insulating body (6) at least one electrically conductive contact pin (6.2) is inserted such that the contact pin (6.4) extends at least from a first end face (6.1) through the ceramic insulating body (6) to a second end face (6.2) opposite to the first end face (6.1), wherein the at least one contact pin (6.4) is further arranged and positioned in the ceramic insulating body (6) such that the distance (d) between the contact pin (6.4) and another electrically conductive component of the pressure transducer at the second end face is not smaller than a value specified in standard DIN 60079-11 (2011 edition) for a gap in air and/or an electrical creepage distance.

Inventors

• Lars Stoltz

Assignees

• 恩德斯豪斯欧洲两合公司

Dates

Publication Date

20260512

Application Date

20240923

Priority Date

20231024

Claims (6)

1. 1. A pressure measuring transducer (1) for transmitting a pressure of a process medium, comprising: -a metal base body (2), the metal base body (2) having a surface (3) and a receiving space (4), the receiving space (4) being for receiving a pressure sensor module (5); The pressure sensor module (5) comprises a ceramic insulating body (6) and a pressure sensor (7), the ceramic insulating body (6) in particular having a substantially cylindrical or conical outer contour, the pressure sensor (7) being placed at a first end (6.1) of the ceramic insulating body, wherein the pressure sensor module (5) is inserted into the metal base body (2) such that the pressure sensor (7) faces an isolation diaphragm (8) and is directed towards the receiving space (4), wherein the ceramic insulating body (6) is also joined with the metal base body on a lateral surface (6.3), -An isolating diaphragm (8), which isolating diaphragm (8) is fixed on the surface (2), wherein a pressure chamber (4) is formed between the isolating diaphragm and the surface, which pressure chamber (4) communicates with a hydraulic path (10) via an opening (4.1) in the surface, which isolating diaphragm (8) is contactable with the process medium on a first isolating diaphragm side (8.1), which pressure chamber (9), which hydraulic path (10) and which receiving space (4) are filled with a pressure-transmitting liquid for transmitting the pressure of the process medium to the pressure sensor; Wherein in the ceramic insulating body (6) at least one electrically conductive contact pin (6.2) is inserted such that the contact pin (6.4) extends at least from the first end (6.1) through the ceramic insulating body (6) to a second end (6.2) opposite the first end (6.1), wherein the at least one contact pin (6.4) is further arranged and positioned in the ceramic insulating body (6) such that the distance (d) between the contact pin (6.4) and the other electrically conductive component of the pressure measuring transducer at the second end is not less than the value specified in standard DIN EN 60079-11 (2011 edition) for air distance and/or creepage prevention distance in air.
2. 2. Pressure measuring transducer according to claim 1, wherein at least a part of a reference pressure path (11) is formed in the ceramic insulating body (6), via which reference pressure path (11) reference pressure can be supplied to the pressure sensor (7), and wherein the at least a part of the reference pressure path (11) formed in the ceramic insulating body (6) is implemented such that the path has a minimum length (l1+l2) which is not smaller than a value specified in standard DIN EN 60079-11 (2011 edition) for air distance and/or creepage prevention distance in air.
3. 3. Pressure measuring transducer according to one or more of the preceding claims, wherein the minimum length (l1+l2) and/or distance (d) is not smaller than the values specified for the air distance and/or creepage prevention distance in air for voltage and protection classes ia, ib of 30V according to table 5 of standard DIN EN 60079-112022 version.
4. 4. Pressure measuring transducer according to one or more of the preceding claims, wherein the minimum length (l1+l2) and/or the distance (d) is not less than 1.5mm, preferably not less than 1.75mm, particularly preferably not less than 2mm.
5. 5. The pressure measuring transducer according to one or more of the preceding claims, wherein the further electrically conductive component of the pressure measuring transducer (1) comprises an edge of the metal base body (2), wherein the ceramic insulating body (6) is joined to the metal base body (2) with its lateral surface (6.3).
6. 6. The pressure measuring transducer according to one or more of the preceding claims, wherein the ceramic insulating body (6) comprises a recess (6.5) on the first end (6.1), the pressure sensor (7) being inserted into the recess (6.5), wherein the recess (6.5) is preferably implemented such that the pressure sensor (7) is inserted into the recess to a maximum height of, for example, half the actual height of the pressure sensor (7).

Description

Pressure transducer for transmitting the pressure of a process medium Technical Field The present invention relates to a pressure measuring transducer for transmitting the pressure of a process medium. Background Pressure measuring transducers for registering pressure are commonly used in industrial pressure measurement technology for absolute pressure measurement, relative pressure measurement and differential pressure measurement. Typically, a first pressure of the medium acts on the isolation diaphragm and is transmitted to the pressure sensor via a first hydraulic pressure transmission path. Typically, the hydraulic pressure transfer path is filled with a pressure transfer liquid to transfer pressure to the pressure sensor. In order to be able to draw the sensor signal of the pressure sensor out of the region under pressure, so-called glass-metal seals are generally used. The pressure sensor is placed on one side of the glass-to-metal seal and the sensor signal is led out of the area under pressure by the contact pins encapsulated by the glass. However, in particular in the process industry, and also in automation technology in general, such pressure measuring transducers are often used in areas where there is a risk of explosion, the so-called explosion hazard areas. For use in an explosion-hazard area, for intrinsically safe equipment protection, the air distance and/or creepage distance between the intrinsically safe current circuit and a grounded metal part, such as a metal platform of a pressure measuring transducer, for example, which is grounded via a container, it is the pressure of the medium in the container that is to be determined. In the case of the use of the above-described glass-metal seals in pressure measuring transducers intended for explosion-hazard areas, the implementation of the required air distance and/or creepage distance can only be achieved with relatively great effort. For example, additional non-electrical conductors are placed between the glass-to-metal seal and the pressure sensor to provide the required air distance and/or creepage distance. A disadvantage of this is that the additional non-electrical conductor must be produced separately and then installed in the pressure measuring transducer. It is therefore an object of the present invention to provide a pressure measuring transducer which can be used in particular in explosion-hazard areas and which is easier to produce. Disclosure of Invention The object according to the invention is achieved by a pressure measuring transducer as claimed in claim 1. The pressure measuring transducer for transmitting the pressure of a process medium of the present invention comprises: a metal base body having a surface and a receiving space for accommodating the pressure sensor module; The pressure sensor module comprises a ceramic insulating body, in particular having a substantially cylindrical or conical outer contour, and a pressure sensor, which is placed at a first end of the ceramic insulating body, wherein the pressure sensor module is inserted into the metal base body such that the pressure sensor faces the isolation diaphragm and is directed towards the receiving space, wherein the ceramic insulating body is also joined with the metal base body on a lateral surface, The isolating diaphragm being fixed on the surface, wherein a pressure chamber is formed between the isolating diaphragm and the surface, the pressure chamber being in communication with a hydraulic path via an opening in the surface, the isolating diaphragm being contactable with the process medium on a first isolating diaphragm face, the pressure chamber, the hydraulic path and the receiving space being filled with a pressure transmitting liquid for transmitting the pressure of the process medium to the pressure sensor; Wherein in the ceramic insulating body at least one electrically conductive contact pin is inserted such that the contact pin extends through the ceramic insulating body at least from the first end to a second end opposite the first end, wherein the at least one contact pin is further arranged and positioned in the ceramic insulating body such that the distance between the contact pin and another electrically conductive component of the pressure measuring transducer at the second end is not less than the value specified in standard DIN EN 60079-11 (2011 edition) for air distance and/or creepage prevention distance in air. An advantageous embodiment of the pressure measuring transducer of the invention may provide that at least a part of a reference pressure path is formed in the ceramic insulating body via which reference pressure can be supplied to the pressure sensor, and wherein the at least part of the reference pressure path formed in the ceramic insulating body is implemented such that the path has a minimum length which is not less than the value specified in standard DIN EN 60079-11 (2011 edition) for the air distance and/or creepage pr