NORGREEN HENRIK (DK)
| EP0152132A1 | 1985-08-21 | |||
| DE2339631A1 | 1974-03-07 | |||
| EP0538930A1 | 1993-04-28 | |||
| EP0202583A1 | 1986-11-26 |
| 1. | A device for determining the flow of liquid in a pipe system, said pipe system having inserted therein an ul¬ trasonic meter which consists of a pipe (1) having a flow duct (3) at whose ends a first measuring transducer (4) and a second measuring transducer, respectively, are ar¬ ranged, said measuring transducers being suspended cen trally and axially with the flow duct, c h a r a c ¬ t e r i z e d in that the measuring transducers are sus¬ pended at the ends of the flow duct by ribshaped means or from a plate having one or more through bores, the size and shape of said through bores being dimensioned for a given liquid flow. |
| 2. | A device according to claim 1, c h a r a c t e r ¬ i z e d in that the transducers are suspended from four ribs (7) . |
| 3. | A device according to claim 1, c h a r a c t e r ¬ i z e d in that the through bores are circular holes or elongate holes positioned concentrically with respect to the centre of the transducer. |
| 4. | A device according to claim 1 or 2, c h a r a c ¬ t e r i z e d in that ribs (7), at the ends facing away from the transducers (4), are secured to a ring (8) hav¬ ing an external diameter which corresponds to the diame ter of the ends of the internal diameter of the flow duct (3) . |
| 5. | A device according to one of claims 1, 2 or 4, c h a r a c t e r i z e d in that electrical connections (13) to the transducers are run inside one of the ribs. |
| 6. | A device according to one of claims 15, c h a r ¬ a c t e r i z e d in that a domeshaped unit (8) is ar¬ ranged in front of the transducers, said unit having a plane face (13) of essentially the same diameter as the diameter of the transducers. |
| 7. | A device according to claim 6, c h a r a c t e r ¬ i z e d in that the domeshaped unit (8) has a cavity extending inwards from the plane face (30) to receive the transducer. |
| 8. | A device according to claim 6 or 7, c h a r a c ¬ t e r i z e d in that the domeshaped unit is secured to the ribs (7) . |
| 9. | A device according to any one of claims 1, 2 or 38, c h a r a c t e r i z e d in that the ribs have a curved shape along their axis of symmetry, such as a convex or a tray shape (9) having a plane face (14) from which the curvature begins at each side of the perpendicular axis of symmetry of the plane face. |
| 10. | A device according to any one of the preceding claims, c h a r a c t e r i z e d in that it is con structed as an independent, exchangeable unit. |
| 11. | A device according to any one of the preceding claims, c h a r a c t e r i z e d in that the flow duct is constructed as a pipe (1) which expands at the ends, e.g. like a funnel (2), or a concavely shaped pipe. |
| 12. | A device according to claims 411, c h a r a c ¬ t e r i z e d in that the ring (8) is constructed such that it forms an extension of the flow duct (3), with a smooth transition between the ring and the funnel. |
| 13. | A device according to any one of the preceding claims, c h a r a c t e r i z e d in that the suspension is made of plastics, optionally enclosed by metal. |
| 14. | A device according to claims 613, c h a r a c ¬ t e r i z e d in that when the transducer is suspended at the inlet to the flow duct, the domeshaped unit and the curved face of the ribs are oriented in a direction away from the inlet to the flow duct. |
| 15. | A device according to claims 613, c h a r a c ¬ t e r i z e d in that when the transducer is suspended at the outlet of the flow duct, the domeshaped unit is oriented in a direction out of the flow duct, while the curved faces of the ribs are oriented inwards toward the outlet of the flow duct. |
The invention concerns a device for determining the flow amount of liquid in a pipe system, said pipe system hav¬ ing inserted therein an ultrasonic meter which consists of a flow duct at whose ends a first measuring transducer and a second measuring transducer, respectively, are ar- ranged, said measuring transducers being suspended cen¬ trally at the ends of the flow duct.
Danish Published Application No. 161258 discloses a meas¬ uring device in which a transducer is mounted at the ends of a measuring pipe. The liquid whose flow amount is to be determined is conveyed via an inlet distribution cham¬ ber to a transducer, which is mounted at one end of a flow duct, and further through the flow duct to the other end at which a second transducer is mounted. This device thus involves a system in which liquid is conveyed into distribution chambers which are staggered with respect to the axial direction of the measuring path. This known de¬ vice therefore requires some mounting space because of the position of the distribution chambers.
European Patent Specification No. 88235 discloses a de¬ vice of the type defined in the introductory portion of claim 1. This known transducer, too, incorporates distri¬ bution chambers which are positioned axially with the flow duct itself in one embodiment. The transducers are suspended centrally in the distribution chambers to the flow duct, without it being indicated at all how the sus¬ pension is constructed.
Accordingly, the object of the invention is to provide a device of the type defined in the introductory portion of
claim 1 which takes up less space and is moreover inex¬ pensive to produce.
The stated object is achieved by the device of claim 1, which is characterized in that the measuring transducers are suspended at the ends of the flow duct, and that they are suspended by rib-shaped means or from a plate having one or more through bores, the size and shape of said through bores being dimensioned for a given liquid flow.
This results in a slender structure, since space-consum¬ ing distribution chambers are no longer required.
When, as stated in claim 3, the transducers are suspended from four ribs, a sturdy suspension is obtained, capable of foxedly securing the transducers even at high liquid flow rates.
When the ribs, at the ends facing away from the trans- ducer, are secured to a ring having an external diameter which corresponds to the diameter of the ends of the in¬ ternal diameter of the flow duct, it is ensured that the transducers are easy to mount in the flow duct.
Further, it is an advantage that electrical connections to the transducers are run inside one of the ribs, since this ensures that the lines do not interfere with the ac¬ tual flow in any way.
With a view to relieving the transducers during the pas¬ sage of the liquid, it is an advantage to mount a dome- shaped unit which has a plane face having essentially the same diameter as the diameter of the transducers.
It is a further advantage when the dome-shaped unit has a cavity extending from the plane face to receive the transducer, as the transducer is hereby protected well.
As the done-shaped unit is secured to the ribs, the transducer is retained very stably and fixedly in the dome-shaped unit.
If the ribs have a curved shape along their axis of sym- metry, such as a convex or tray shape with a plane face from which the curvature begins at each side of the per¬ pendicular axis of symmetry of the plane face, it is en¬ sured that the liquid flow through the duct is disturbed as little as possible.
Expedient embodiments of the device of the invention are defined in the dependent claims in general.
The invention will now be explained more fully with ref- erence to an example shown in the drawing, in which:
fig. 1 is sectional view of the device according to the invention,
fig. 2 shows the transducer with suspension according to the invention,
fig. 3 shows a dome-shaped unit to protect the trans¬ ducer,
fig. 4 is a perspective view of an embodiment of a rib to secure the transducer, and
fig. 5 is a cross-sectional view of a ring to secure the ribs of fig. 4.
As will be seen in fig. 1, a device for determining the flow of a liquid in a pipe system consists of a pipe 1 having a duct 3 which is terminated at both ends by a funnel 2. A small pipe section having threads is arranged in extension of the funnel 2 and is intended to receive a gasket ring 6 adapted to engage the bottom of the small pipe section. A transducer 4 may be engaged at the oppo¬ site side of the gasket ring 6 and be tightened by means of a nut 5.
As shown in fig. 2, the transducer 4 is suspended cen¬ trally by means of ribs 7, whose opposite ends with re¬ spect to the transducer are terminated by a ring 8.
This structure may be inserted in a simple manner by means of the gasket ring 6 and be tightened by means of the nut 5, as shown in fig. 1.
Fig. 3 schematically shows an embodiment in which the transducer 4 is protected by a dome-shaped unit 8, which has a base face 13 having essentially the same diameter as the transducer 4. In general, the dome-shaped unit may be constructed with a depression (not shown) in which the transducer may be positioned and be well protected there.
Fig. 4 shows a preferred embodiment of the ribs 7, as these are formed with a convex or tray shape, which also contributes to ensuring that liquid flowing through the flow duct 3 of fig. 1 is disturbed as little as possible.
Finally, fig. 5 shows a cross-section of the ring 8 which has two faces 11, 12 capable of engaging the small pipe in fig. 1, more particularly the gasket ring 6 with the face 12 and with the face 11 along the inner surface of the small pipe. Fig. 5 additionally shows that the ring 10 has a curved surface 10 which may be dimensioned for
the funnel 2 in fig. 1 so that the face 10 merges evenly into the funnel 2.
Although the invention has been explained in connection with a particular embodiment according to figs. 1 to 5, nothing prevents it from being modified within the scope of the invention. For example, the dome-shaped unit may be shaped more pointedly than shown in fig. 3. The same applies to the ribs shown in fig. 2 and fig. 4.