Vibration-type measuring transducer

Abstract

The measuring transducer comprises a measuring tube which vibrates at least temporarily during operation and has the purpose of conducting the medium, the measuring tube communicating with the tube line via an inlet tube element which leads in at the inlet side and via an outlet tube element which leads in at the outlet side, and a counter-oscillator which is secured to the measuring tube at the inlet side so as to form a first coupling zone and which is secured to the measuring tube at the outlet side so as to form a second coupling zone.; Furthermore, the measuring transducer comprises a first extension arm for generating flexural torques in the inlet tube element which is coupled essentially rigidly to the inlet tube element and the measuring tube in the region of the first coupling zone and which has a centroid lying in the region of the inlet tube element, and a second extension arm for generating flexural torques in the outlet tube element which is coupled essentially rigidly tothe outlet tube element and the measuring tube in the region of the second coupling zone and which has a centroid lying in the region of the outlet tube element. The measuring transducer according tothe invention is particularly also suitable for measuring tubes with a large nominal diameter of more than 50 mm.

Description

technical field [0001] The invention relates to a vibrating measuring transducer, in particular to a vibrating measuring transducer suitable for a Coriolis mass flow meter. Background technique [0002] In order to determine the mass flow rate of a medium flowing in a pipeline, especially a liquid, a measuring device is often used, which uses a vibrating measuring transducer and associated control and regulation electronics, which generate Coriolis forces in the medium and are controlled by these Force to obtain a measurement signal representing mass flow. [0003] Such Coriolis mass flow meters are already known and widely used in industry. Thus, for example in EP-A 317 340, US-A 53 98 554, US-A 54 76 013, US-A 5531 126, US-A 56 91 485, US-A 57 05 754, US-A 57 96 012 , US-A 59 45609, US-A 59 79 246, US-A 60 06 609, US-B 63 97 685, US-B 66 91 583, US-B 68 40 109, WO-A 99 51 946, WO - Coriolis mass flow meters as described in A 99 40 394 or WO-A 00 14 485, each having a me...

AI Technical Summary

Problems solved by technology

[0017] However, further investigations have shown that, although very good results regarding interference immunity can in principle be obtained with the decoupling mechanisms proposed in US-B 66 91 583 and US-B 68 40109, for certain applications, especially in For applications in which the density of the medium fluctuates in a very wide range, the bandwidth of the decoupling mechanism is too small with the disclosed construction and because of this unsatisfactory results are not obtained with regard to the interference immunity of the measuring transducer

However, it has also been determined that the mere application of a relatively heavy anti-oscillator as suggested in US-A 52 87 754, US-A 57 05 754, US-A 57 96 010 or US-B 69 48 379 does not significantly improve Decoupling mechanism given in US-B 66 91583 and US-B 68 40 109

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