초록 ▼

This galvanic electrode of a flow sensor of an electromagnetic flowmeter for measuring the volumetric flow rate of an electrically conductive liquid flowing in a measuring tube is practically absolutely fluid-tight inserted in the wall of the measuring tube and has a highly constant wetting surface.

This galvanic electrode of a flow sensor of an electromagnetic flowmeter for measuring the volumetric flow rate of an electrically conductive liquid flowing in a measuring tube is practically absolutely fluid-tight inserted in the wall of the measuring tube and has a highly constant wetting surface. The electrode comprises a shank having a first portion which is fitted fluid-tightly in a hole in the wall, an end face and a second portion having a smaller diameter than the hole and the first portion. A wetting surface formed by the end face and a second portion of the electrode shank. This second portion forms a gap between the surface of the hole. The gap is sufficiently wide and the surface of the hole has a low surface tension so that the liquid will penetrate into and fill the gap, and the wetting surface will remain constant under all operating conditions of the flowmeter.

대표청구항 ▼

[ We claim:] [1.] A galvanic electrode of a flow sensor of an electromagnetic flow meter for measuring the volumetric flow rate of an electrically conductive liquid flowing in a measuring tube having a metallic part and an electrically non-conductive part contacting the liquid and extending through

[ We claim:] [1.] A galvanic electrode of a flow sensor of an electromagnetic flow meter for measuring the volumetric flow rate of an electrically conductive liquid flowing in a measuring tube having a metallic part and an electrically non-conductive part contacting the liquid and extending through a hole in a wall of the measuring tube thereby forming an extension, the electrode being inserted into a constant-diameter hole extending through the extension from an outer side of the extension, which is not in contact with the liquid, to an inner side of the extension, which is in contact with the liquid, the electrode comprising:an electrode shank havinga first portion which is fitted fluid-tightly in the constant-diameter hole from the outer side of the extension with a permanent radial mechanical prestress, anda second portion havinga smaller diameter than the constant-diameter hole and the first portion,an end surface, anda surface adjoining the end surface,a wetting surface formed by the surface adjoining the end surface and by the end surface which is wettable by the liquid,the surface adjoining the end surface of the second portion of the electrode shank and a surface of the constant-diameter hole forming a gap, andthe gap being sufficiently wide and the surface of the constant-diameter hole having a low surface tension so that the liquid will penetrate into and fill the gap and the wetting surface will remain constant under all operating conditions of the flowmeter.