GB2073893A

GB2073893A - Flow control and measuring apparatus

Info

Publication number: GB2073893A
Application number: GB8111941A
Authority: GB
Original assignee: TACO ARMATUREN AG
Current assignee: TACO ARMATUREN AG
Priority date: 1980-04-16
Filing date: 1981-04-15
Publication date: 1981-10-21
Also published as: IT1170899B; NL8101856A; SE8102452L; FR2480936A1; IT8148299A0; DE3115572A1

Abstract

A flow meter 1 is incorporated into the housing of a rotatable control valve 15. The meter comprises a spring loaded piston 11 in a transparent tube 6. <IMAGE>

Description

SPECIFICATION Flow control apparatus The present invention relates to a flow control apparatus.

DESCRIPTION OF THE PRIOR ART Flow control apparatuses are commonly designed as control valves having a valve closure body operated by a valve spindle, which spindle is provided, for instance with a hand wheel for operation of the valve. To allow the controlling of the volume flow the movable spindle as well as a fixed part of the valve casing are provided with a graduation scale and an index marking. Upon rotation of the spindle the index marking is moved relative to the graduation. The prior art has developed now mainly two designs of such apparatuses.

One design encompasses a scale graduation arranged along the spindle such that the axial displacement of the spindle forms a measure representing the prevailing volume flow through the apparatus. Another design comprises a scale graduation extending along the circumference of the spindle whereby the prevailing angle of rotation of the spindle forms the measure for indicating the prevailing volume flow through the apparatus. Such control valves are manufactured in large batches and, therefore, cost considerations do not allow that every control valve can be tested on a test stand in order to adjust and set exactly the scale for the index marking exactly within the complete control range to insure that the position of the scale graduation corresponds exactly to the prevailing flow volume. Accordingly a relatively large spread of indication errors appears due to manufacturing tolerances.In use of such a flow control apparatus it is only possible to rely on the position of the index marking relative to the scale graduation; however, it is not possible to check how much the actual flow volume deviates from the desired value. It further is impossible to ascertain upon rotating the spindle of the valve by only a small amount how such adjusting influences directly an increase or decrease, respectively, of the flow volume. Such inaccuracies are specifically in such cases a drawback in which several line conduits are present arranged parallel to each other, which line conduits should be adjusted regarding the volume flow relative to each other.Such line conduits may be present, for instance, in an apartment house comprising several user systems of hot water such as, for instance, a heating at the south side of the building, the heating at the north side of the building, the air conditioner and domestic water needs. Every group of users (every line conduit) should in such case be provided with a predetermined volume flow of water, for instance, measured in liters/ minutes. In such cases the known control valves would have been used as flow control apparatus. Accordingly, every line conduit must be adjusted relative to the others by adjusting the control position of the valves.

This adjusting relative to each other may be considered as adjusting the energy transport to every single user's group. This adjusting of the volume flows at the various line conduits such as, for instance, in heating systems, can be achieved when using the known control valves only after considerable expense and time and will still suffer considerable instability factors. The line conduit or pipe, respectively, network adjusted by means of the known control valves corresponds hardly to the originally designed distribution of energy.

Such leads to dissimilarly heated rooms of an apartment and to not optimally used heating surfaces. Should a user be provided with own control systems, such control systems can be disturbed by the non-optimal transport of energy.

SUMMARY OF THE INVENTION Hence, it is a general object of the present invention to provide an improved construction of a flow control apparatus which allows a substantially exact adjusting of through flow volumes of several parallel line conduits.

Now, in order to implement this and still further objects of the invention, which will become more readily apparent as the description proceeds, the flow control apparatus of this development is manifested by comprising a casing; a flow channel; a window arranged in said flow channel; a piston displaceably arranged in said flow channel, which said displaceable piston is intended to be acted upon by a liquid medium flowing through said flow channel such to be moved thereby along said window; a helical spring arranged in said flow channel, which said helical spring engages at one end said displaceable piston and at the other end a portion of said casing; a graduation marking provided at stationary casing parts and at said displaceable piston and intended to indicate the position of said displaceable piston along said graduation marking.

If now, every line conduit into which there is mounted such a flow control apparatus is provided further with a flow control valve, a minimal adjustment of this control valve can be viewed through the window in the apparatus by checking the displacement of the piston in the flow channel, which piston is displaced along the index scale. Because now the results of an adjustment of the control valve can be visibly indicated by the agency of the increase or decrease of the flow velocity in the flow channel and, therfore, the displacement of the piston along the scale graduation, it is possible to achieve above mentioned adjusting of the various line conduits relative to each other much easier than hither to possible. A specific advantageous design foresees an integrating of the previous mentioned control valve into the flow control apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be more fully understood by reference to the following detailed descriptions thereof, when read in conjunction with the attached drawings, and wherein: Figure 1 is a sectional view through a first embodiment of a flow control apparatus constructed according to the present invention; Figure 2 is a sectional view through a second embodiment of the flow control apparatus designed according to the present invention; and Figure 3 is a top view of the apparatus shown in Fig. 2, whereby parts are shown partly broken away.

DETAILED DESCRIPTION OF THE PRE FERRED EMBODIMENTS Describing now the drawings, and considering initially the exemplary embodiment of the flow control apparatus 51 as shown in Fig. 1, it will be understood that same comprises a casing 1 made, for intance, from a pressed yellow brass. This casing 1 comprises a center body 2 provided at one end with a hexagon head 3 and at the other end with a male thread 4. The hexagon head 3 comprises a female thread 52 such to allow a mounting of the apparatus 51 to not particularly shown pipes. The casing 1 comprises a fluid flow channel 5. The casing 1 comprises two through holes 6 arranged diametrically opposite to each other, which through holes 6 extend to the fluid flow channel 5 and thus define windows 6 in this fluid flow channel. A tube section 7 made from a transparent material is arranged within the fluid flow channel 5.This tube section 7 can be made preferably from a plastics material. The tube section 7 is mounted sealingly inside the housing 1 whereby two O-rings 8 and 9 form the respective seals. A disk 10 made preferably also from yellow brass is arranged, furthermore, within the fluid flow channel 5, which disk 10 is mounted with a press fit in the fluid channel 5 and accordingly exerts a pressure against the tube section 7 such that this tube section 7 is held axially in casing 1 such that it cannot be displaced. The edge of one of the through holes 6 is provided with a graduation 6', which extends, for instance from the numerals 1 to 5.

A sleevelike piston 11 is axially displaceably guided within mentioned tube section 7. This sleevelike piston 11 is made of a material having a specific gravity which is as close as possible to the specific gravity of the prevailing flowing medium. Between a face 53 of the casing 1 and the sleevelike piston 11 there is arranged a helical pressure spring 12, which abuts at one end 62 casing 1 and is seated with its other end 61, that is, with one coil in a groove 52 on the sleevelike piston 11. Accordingly, piston 11 of Fig. 1 can be displaced against the force of the spring 1 2 to the right within the tube section 7.Piston 11 comprises a face surface 1 3. The apparatus 51 as shown in Fig. 1 is flowed through by a flowing liquid medium in direction of the arrow 1 4, such that this flowing liquid medium flows partly against the face surface 1 3 of the sleevelike piston 11. Accordingly, due to its face surface 1 3 this sleevelike piston 11 acts as a flow resistance within the tube section 7.The higher the velocity of flow of this liquid medium is, the more the sleevelike piston 11 of Fig. 1 will be displaced to the right at a simultaneous compression of spring 1 2. The prevailing volume flow per time unit is adjusted and set by means of the flow control valve 1 5. The construction or design, respectively, of this control valve 1 5 is generally known.It comprises a rotatable shut-off member in form of a spherical valve body 1 6 provided with a fluid flow channel 1 7. This valve body 1 6 is sealingly seated by the agency of O-ring 55 within casing 1 and can be rotated by means of a slotted adjusting plug 18, which slot 56 receives a hand tool, for instance, a screwdriver for operating the valve body 1 6. This operating or rotating, respectively, of the valve body 16 leads to a more or less opening of the cross-sectional area of the fluid flow channel 1 7 relative to the fluid flow channel 5 surrounding such.

Conclusively, the control valve 1 5 controls the cross-sectional area of the fluid flow channel.

Because the adjustments or changes, respectively, of the cross-sectional area of the fluid flow channel generates in a known way at the control edges of the fluid flow channel 1 7 erratic and irregular flow speeds and accordingly produces turbulences, that is, a nonuniform cross-sectional flow speed, this controlling or adjusting, respectively, of the crosssectional area is arranged seen in direction of flow behind the sleevelike piston 11. Conclusively, piston 11 is also acted upon by an undisturbed fluid flow.

The transparent tube section 7 is visible through the through hole 6 provided with a scale graduation 6' and a person can seen through this transparent tube section 7 and view the edge 57 of the sleevelike piston 11 at its face surface 1 3. This rear edge 57 of piston 11 seen in direction of flow through the apparatus 51 is the index marker of the apparatus which coacts with the scale graduation 6' formed on one of the through holes 6.

According to the embodiment shown in Fig. 1 the face surface 1 3 is located at value 1.1 of this scale. Thereby the valve body 1 6 of the control valve 1 5 will be adjusted to a considerably reduced position within the flow chan nel, which, however, is not shown in Fig. 1 for sake of clarity. If, however, the valve body 1 6 is in a position in which it gives the flow channel completely free, which position is shown in Fig. 1 at the control valve 15, the sleevelike piston 11 could, for instance, be located with its face surface 1 3 at the mark 5 of the graduation.

The practical embodiment shown in Fig. 1 has, for instance, been embodied for a 2 inch water tube. This flow control apparatus is in such case designed for a range of flow between 0 and 5 liters/minute and can be used in hot water heating systems which operate, for instance, with radiators or can be used for a floor heating and systems having collectors for solar energy.

Although it has been mentioned earlier that only one of the through holes 6 is provided with a scale graduation 6' such that in order to allow viewing the position of the sleevelike piston 11 only this one through hole 6 in the casing 1 would be necessary, practical embodiments have shown that it is advantageous to arrange two through holes 6 located diametrically opposite to each other because this design allows the transparent tube section 7 to be lightened much better by incoming light such that the position of the sleevelike piston 11 can be viewed much better.

The helical spring 1 2 used for the apparatus as shown in Fig. 1 has a quite flat distribution of the spring stiffness, that is, this spring is a very soft spring, whereby in a practical execution this helical spring 1 2 has been made from a wire having a diameter of 0.2 mm. To construct the sleevelike piston 11 a plastics material has been used which has about the same specific gravity as water such that the piston 11 is held in water practically without any buoyancy. Because, accordingly, the deadweight of the piston 11 together with the spring 1 2 can be neglected, the apparatus shown in Fig. 1 may be arranged in a pipe conduit in a lying or in a standing position.

Reference is made now to Figs. 2 and 3, in which there is shown a further preferred embodiment of the flow control apparatus identified by the reference numeral of 58.

This embodiment shown in Figs. 2 and 3 comprises a bipartite casing of the apparatus consisting of a first casing part 1 9 and a second casing part 20. The first casing part 1 9 is mounted rigidly and is provided to this end with two coupling stubs 21 and 22 to allow a coupling or connecting, respectively, to pipes. This second casing part 20 is arranged within the first casing part 1 9 and is rotatably mounted therein, whereby the second casing part 20 can be rotated about 90 .

Both casing parts 1 9 and 20 are fluid tight mounted by means of four O-rings 23, 24, 25 and 26 relative to each other. Two further sealing rings 27 and 28 are mounted additionally within the rigidly held casing part 1 9.

These annular sealing rings 27 and 28 are made of a relatively hard plastics material.

The sealing ring 27 carries a O-ring 25, and the sealing ring 28 carries the O-ring 26. The second casing part 20 is held within the first casing part 1 9 by means of a cover 29, which is mounted to the first casing part 1 9 by the agency of several screw bolts 30. For ease of assembly the face surfaces 59 and 62 of the sealing rings 27 and 28 of Fig. 2 facing each other according to Fig. 2 are arranged such that they converge downwardly. The rotatable second casing part 20 will then be inserted into the first casing part 1 9 from above as viewed in Fig. 2 and thereafter the cover 29 is applied.

The rotatable second casing part 20 is provided with two diametrically opposed arranged through holes 31 such as is the case at the first preferred embodiment shown in Fig. 1. These through holes form a window each for the inner tube section 32, which tube section 32 consists of a transparent material, for instance, of a plastics material.

According to Fig. 3 the through hole 31 arranged as seen in Fig. 2 at the top is followed by a graduation or scale 33, respectively. This graduation extends, for instance, from the value 2 to the value 22. The transparent tube section 32 is sealingly held by the agency of two Rings 34 and 35 within a channel 36 of the second casing part 20.

Within this tube section 32 a sleevelike piston 37 and a helical pressure spring 38 are mounted such as is the case in the first preferred embodiment shown in Fig. 1. Piston 37 is provided with a face surface 39. The rigidly held casing part 1 9 comprises a fluid flow channel 40, which is defined by the through bores of the two sealing rings 27 and 28.

From Fig. 3 it can be seen that the stationary first casing part 1 9 is provided with an access opening 41, which access opening 41 is arranged staggered to the fluid flow channel 40 of the first stationary casing part 1 9 by an angle of rotation of 90t. This access opening 41 allows an extracting of the tube section 32 inclusive the piston 37 and the spring 38 arranged therein after the rotatable second casing part 20 has been rotated from its position shown in Fig. 3 by 90 . In this rotated position of the second casing part 20 the flow channel 36 of the rotatable second casing part 20 is aligned with the access opening 41 such that in this position also the structural members 32, 37 and 38 can be extracted out of the second casing part 20 and also out of the first casing part 1 9. In the assembled condition of the apparatus of Fig.

3 this access opening 41 is closed by means of a cover plate 42. The liquid flow medium flows in direction of arrow 1 4 through the apparatus. A flow control valve 15' is mounted in the stationary first casing part 1 9 behind piston 37 viewed again in direction of flow.

The rotating of the second casing part 20 together with the members 32, 37 and 38 towards the access opening 41 can proceed in various ways. For instane, the second casing part 20 is provided with two recesses 43, into which the plugs of a known tool can be inserted. Accordingly, this second casing part 20 may be rotated by operating this tool similarly to a rotating valve through 90'.

Upon rotating this second casing part 20 together with its members 32, 37 and 38 towards the access opening 41 several objects can be achieved. Because the second casing part 20 acts in the same way as a rotary valve, its flow channel 36 is blocked against the flow channel 40 of the first casing part 19, i.e. no fluid flow proceeds through the apparatus. If now the drain plug 44 is removed, the fluid pipe or conduit line system mounted to the coupling plug 22 can be drained. Besides the blocking function by the agency of the second casing part 20 it is now possible to dismount the transparent tube section 32, the piston 37 as well as the spring 38. This can be made, for instance, for cleaning purposes, however, also in order to, for instance, exchange spring 38 against another spring having a different spring stiffness.In such case it is merely necessary to replace the scale graduation 33 by a differently graduated scale. In this way the usable range of the apparatus could be broadened.

The more complicated constructed and accordingly more expensive apparatus of Fig. 3, this in comparison with the embodiment shown in Fig. 1, can be used for connecting one-inch or two-inch pipes. Accordingly, this appratus can be designed for a flow volume of, for instance, 100 iters/minute.

Both shown and described embodiments of the apparatus can have a graduation scale designed on the transparent tube sections 7 or 32, respectively. In this way it is also possible to provide every transparent tube section with two different graduations whereby obviously at any time only one of the two graduations may be seen at an installed apparatus. Accordingly, such two graduations are arranged staggered along the circumference of this transparent tube section 7 such that at any given time only one of the two graduations is visible. If now a spring having a different spring stiffness is used, it is merely necessary to rotated the transparent tube section around irs longitudinal axis until the other graduation corresponding to the new spring stiffness can be viewed through the through hole 6 or 31, respectively, acting as window.

It is possible to adjust a sought water flow volume by means of the control valves 1 5 or 1 5', respectively. by checking the displacea ble pistons 11 or 37, respectively. which given an optical exact indication of the volume flow and therefore an extremely exact adjusting of the volume flow is possible.

While there are shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto, but may be otherwise variously embodied and practiced within the scope of the following claims.

Claims

1. A flow control apparatus, characterized by at least one window arranged in a flow channel, by a piston displaceably arranged in said flow channel, which piston can be acted upon by a flowing liquid and accordingly be moved along said window, by a helical spring arranged in said flow channel which engages at one end said piston and at the other end a casing portion of said flow control apparatus, and by a graduation marking arranged on stationary casing parts and on said displacea- ble piston intended to indicate the position of said piston along said graduation.

2. The flow control apparatus as defined in claim 1, characterized in that said casing is provided with a flow control valve which is arranged behind said piston relative to the direction of flow therethrough.

3. The flow control apparatus as defined in claim 1, characterized in that said window is provided by a tube section made of a transparent material and arranged in a channel of said casing, whereby said channel of said casing is provided with at least one through hole exposing said transparent tube section therethrough.

4. The flow control apparatus as defined in claim 1, characterized in that said piston is a sleevelike member having a face surface extending transversely relative to said flow channel and intended to be acted upon by said flowing liquid.

5. The flow control apparatus as defined in claims 3 and 4, characterized in that said sleevelike piston is guided by and within said transparent tube section.

6. The flow control apparatus as defined in claims 1 and 3, characterized in that said casing has a tubelike shape and is provided at both its ends with a pipe connector, further in that said through hole is arranged in said casing, and in that said transparent tube section is sealingly arranged in said casing.

7. The flow control apparatus as defined in claims 1 and 3, characterized in that said casing is bipartite, that said casing parts are arranged inside each other, rotatable relative to each other and fluid-tight sealed relative to each other, whereby a first casing part is provided at two ends with pipe connectors and the second casing part is located inside said first casing part, and whereby a channel of said second casing part comprises said tube section including said piston and said helical spring. and in that said first casing part is provided with an access opening which is arranged staggered in direction of rotation relative to said flow channel, further in that the flow channel of said second casing part can be aligned with said removing opening such to allow a removal of said piston and of said helical spring from both said casing parts.

8. The flow control apparatus as defined in claim 7, characterized in that said second casing part is shaped and arranged as a rotary slide valve which is rotatable into a position relative to said first casing part in which said flow channel of said first casing part is blocked by said second casing part acting as a rotary slide valve, whereby in said rotated position of said second casing part relative to said first casing part said removing opening is aligned with said flow channel of said second casing part.

9. The flow control apparatus as defined in claim 1, characterized in that an index marking of said graduation marking is provided by the rear edge of said piston seen in direction of flow through said flow control apparatus.

10. The flow control apparatus as described and shown in Fig. 1.

11. The flow control apparatus as described and shown in Figs. 2 and 3.