DE202007011915U1 - Modular meter - Google Patents

Abstract

Modular measuring device (1), comprising:
a sensor module (20) having a converter for providing an electrical sensor signal dependent on a measured variable; and
an electronic module (10) which comprises a housing (11) which has a chamber (12) which is open toward the sensor module (20) and in which circuit components (14) for processing the sensor signal and an end section of the sensor module (20) are arranged, wherein the remaining volume in the chamber (12) is at least partially potted; characterized in that the chamber (12) includes a first potting compound (17) covering the circuit components (14) and a second potting compound (18) at least partially covering the surfaces of the end portion of the sensor module in the chamber; Potting compound has different mechanical properties than the first potting compound.

Description

The The present invention relates to modular meters, in particular potentiometric measuring instruments, amperometric measuring instruments, Conductivity meters, turbidity meters and measuring equipment for other physical or chemical Measured variables, in particular in the field of industrial Process measurement.

One generic measuring device includes a Sensor module with a converter for providing one of Measured variable dependent electrical sensor signal and an electronic module comprising a housing which towards the sensor module has an open chamber, in which circuit components arranged for processing the sensor signal and an end portion of the sensor module are, with the remaining volume is shed in the chamber.

The Applicant manufactures, for example, a modular pH meter called "Memosens", which comprises as a sensor module a pH combination electrode on which an electronic module with an inductively coupling interface to a data and energy transmission line is arranged Measuring devices are for example the unpublished patent applications DE 102007008072 and DE 102007008074 and as well as utility models 202007004799 refer to.

Under Everyday conditions will be a pH sensor for calibration from the measuring point removed and taken to a laboratory. This can on the one hand forces act on the sensor module and on the other hand on the electronics module, which at the contact point between the sensor module and the electronic module meet each other and in extreme cases to damage to lead.

equally can generate high frequency vibrations from the environment of the sensor module via the Sensor module can be coupled into the electronics module and itself in this respect long term on the durability of the circuit components impact.

It is therefore the object of the invention, the generic Optimize meter.

The Task is solved by the measuring device according to independent claim 1.

That Measuring device according to the invention comprises Sensor module with a converter for providing one of Measured variable dependent electrical sensor signal and an electronic module comprising a housing which towards the sensor module has an open chamber, in which circuit components arranged for processing the sensor signal and an end portion of the sensor module are, with the remaining volume in the chamber at least partially is shed; characterized in that the chamber is a first potting compound which covers the circuit components, and a second potting compound, which the surfaces of the end portion the sensor module in the chamber at least partially covered, wherein the second potting compound has other mechanical properties as the first potting compound.

In a presently preferred embodiment of the invention is the second Potting compound softer than the first potting compound.

In a development of the invention comprises the first potting compound a high temperature 2 component epoxy resin with filler.

In In a further development of the invention, the electronic module comprises a Board, being arranged on the board circuit components are, and wherein the circuit board and the circuit components at least with the first potting compound opposite the opening the chamber are completed.

In a development of the invention comprises the second potting compound a soft modified, unfilled epoxy resin with high Chemical resistance.

In In a further development of the invention, the sensor module comprises a potentiometric sensor, with a glass shaft, in particular one Combination electrode, wherein the end portion of the glass shaft in the Chamber is arranged, and a surface of the end portion in the chamber opposite the opening of the chamber is completed with the second potting compound.

The Invention will now be described with reference to the embodiment shown in the drawing explained.

It shows:

1 : A longitudinal section through an electronics module-side end portion of a modular pH meter according to the invention.

This in 1 illustrated modular pH meter 1 includes an electronics module 10 and a sensor module 20 ,

The electronics module has a plastic housing 11 with a chamber 12 on, in which a circuit board 14 is provided with circuit components, wherein on the board contact points 15 disposed are at which the sensor module 20 is connected, as described below.

The circuit components convert an analog sensor signal into a digital signal, which inductively via a toroidal coil 16 on a sensor module 20 remote end portion of the housing 11 is decoupled.

The sensor module 20 In the exemplary embodiment comprises a combination electrode with a glass shaft 21 whose end section is in the chamber 12 is arranged. signal lines 22 for pH and reference potential as well as temperature and mass are at the contact points 15 connected. The board 14 with the circuit components is up to at least its upper edge with a first potting compound 17 opposite the opening of the chamber 12 completed, wherein the first potting compound comprises a high-temperature two-component epoxy resin with filler.

An annular gap between the end portion of the glass shaft 21 and a surrounding wall of the chamber 12 is with a second potting compound 18 which is softer than the first potting compound, whereby the mechanical coupling between the glass shaft 21 and the housing 11 is reduced.

The second potting compound 18 includes, for example, soft modified, unfilled epoxy resin with high chemical resistance.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 102007008072 U [0003]
• - DE 102007008074 U [0003]
• - DE 202007004799 U [0003]

Claims (6)

Modular measuring device ( 1 ), comprising: a sensor module ( 20 ) with a converter for providing an electrical sensor signal dependent on a measured variable; and an electronics module ( 10 ), which is a housing ( 11 ), which one to the sensor module ( 20 ) open chamber ( 12 ), in which circuit components ( 14 ) for processing the sensor signal and an end portion of the sensor module ( 20 ), the remaining volume in the chamber ( 12 ) is at least partially shed; characterized in that the chamber ( 12 ) a first potting compound ( 17 ) containing the circuit components ( 14 ), and a second potting compound ( 18 ), which at least partially covers the surfaces of the end portion of the sensor module in the chamber, wherein the second potting compound has different mechanical properties than the first potting compound. Apparatus according to claim 1, wherein the second potting compound softer than the first potting compound. Apparatus according to claim 1 or 2, wherein the first Potting compound a high-temperature two-component epoxy resin with filler includes. Device according to one of claims 1 to 3, wherein in an embodiment of the invention, the electronic module comprises a circuit board, wherein on the circuit board circuit components ( 14 ) are arranged, and wherein the circuit board and the circuit components at least with the first potting compound ( 17 ) opposite the opening of the chamber 12 ) Are completed. Device according to one of claims 1 to 4, wherein the second potting compound a modified, unfilled Epoxy resin with high chemical resistance includes. Device according to one of claims 1 to 5, wherein the sensor module ( 20 ) a potentiometric sensor, with a glass shaft ( 21 ), in particular a combination electrode, wherein the end portion of the glass shaft ( 21 ) in the chamber ( 12 ), and a surface of the end portion in the chamber (FIG. 12 ) is completed with respect to the opening of the chamber with the second potting compound.