EP0423169A1 - Registre - Google Patents

Registre

Info

Publication number
EP0423169A1
EP0423169A1 EP19890907354 EP89907354A EP0423169A1 EP 0423169 A1 EP0423169 A1 EP 0423169A1 EP 19890907354 EP19890907354 EP 19890907354 EP 89907354 A EP89907354 A EP 89907354A EP 0423169 A1 EP0423169 A1 EP 0423169A1
Authority
EP
European Patent Office
Prior art keywords
casing
damper
damper elements
elements
angle
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP19890907354
Other languages
German (de)
English (en)
Inventor
Knut Bergdahl
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of EP0423169A1 publication Critical patent/EP0423169A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/08—Air-flow control members, e.g. louvres, grilles, flaps or guide plates
    • F24F13/10—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers
    • F24F13/14—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre
    • F24F13/1426—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre characterised by actuating means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K1/00—Lift valves or globe valves, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces
    • F16K1/16—Lift valves or globe valves, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces with pivoted closure-members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/08—Air-flow control members, e.g. louvres, grilles, flaps or guide plates
    • F24F13/10—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers
    • F24F13/14—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre
    • F24F13/1413—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre using more than one tilting member, e.g. with several pivoting blades
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/08—Air-flow control members, e.g. louvres, grilles, flaps or guide plates
    • F24F13/10—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers
    • F24F13/14—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre
    • F24F13/1426—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre characterised by actuating means
    • F24F2013/1446—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre characterised by actuating means with gearings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/08—Air-flow control members, e.g. louvres, grilles, flaps or guide plates
    • F24F13/10—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers
    • F24F13/14—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre
    • F24F13/1426—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre characterised by actuating means
    • F24F2013/1473—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre characterised by actuating means with cams or levers

Definitions

  • This invention is related to a damper device comprising a fl conveying casing having a curved wall and two damper elemen pivotably arranged in the casing.
  • the damper device is pr ferably intended for air flow regulation in ventilati arrangements.
  • Damper devices of various kinds are previously known but suff from several problems.
  • One of these problems resides in t noise generated by the turbulence of the air around dampers a shafts.
  • Another problem relates to the regulation characte ristics of the dampers.
  • a linear characteristic is aimed at i.e. the pivoting angle of the damper should preferably b proportional to the flow.
  • Prior dampers e.g. so calle throttle dampers and iris dampers, present a regulatio characteristic which considerably deviates from the linear one
  • the object of the present invention is to provide a damper device having such a structural design that the problems discussed hereinabove are eliminated or at least reduced.
  • fig 1 is a side view of the damper device in its open position, a portion of the casing being cut away;
  • fig 2 is a view of the damper device as viewed from the left in fig 1? --,
  • fig 3 is a view of the damper device as viewed from above fig 1, i.e. parallel to its pivot axis, a portion of the casi and the operating arrangement having been removed;
  • fig 4 is a view similar to fig 3 but illustrating the device a closed position
  • fig 5 is an enlarged basic view illustrating one of the damp elements in its extreme positions
  • fig 6 is an enlarged view illustrating an operating arrangeme for the damper elements
  • fig 7 is a view of the operating arrangement as viewed from t right in fig 6;
  • fig 8 is a view illustrating the damper elements in a plana flattened state
  • fig 9 is a diagram illustrating the relation flow q and degr ⁇ of opening of the damper
  • fig 10 is a view similar to fig 2 of an alternative embodimen
  • fig 11 is a view similar to figs 3 and 4 of the alternati embodiment according to fig 10;
  • fig 12 is a side view similar to fig 1 of another alternati comprising another damper element shape and another operati arrangement, the damper elements being in open position;
  • fig 13 is a view of fig 12 from above, the casing being part cut away and some other parts removed for gaining clarity;
  • fig 14 is a view similar to fig 13 but illustrating the damp elements in a closed position
  • fig 15 is a view similar to figs 3 and 4 of a third alternative for the damper device
  • fig 16 is a view similar to fig 15 of a fourth alternative embodiment.
  • the damper device comprises a flow conveying casing 1 with a curved mantle wall and two damper elements 2, 3 pivotably arranged in the casing. These elements are curved generally in correspondence to the wall of the casing and adapted to coope ⁇ rate so that they in a closed position (fig 4) in unison generally shut off or at least reduce the flow through the casing. In their open positions (figs 1-3) the damper elements are located generally along the interior side of the casing wall while delimiting between themselves an entirely open channel extending in the longitudinal direction of the casing.
  • the casing 1 is generally circular in cross section and each of the damper elements 2, 3 is generally semi-circularly curved.
  • each of the damper elements comprises lugs 6 provided with holes.
  • damper elements 2, 3 In the duct space delimited in unison by the damper elements 2, 3 in their open position (see fig 2) there is no shaft exten ⁇ ding transversely relative to the casing. Instead, the damper elements 2, 3 are at the bottom of the view according to figs 1 and 2 pivotably connected to the casing by means of a short stub axle 7 projecting through the holes in the lower lugs 6. The design at the top appears most clearly from figs 6 and The damper elements 2, 3 are pivotable by means of a ge transmission 8 comprising two gears 9, 10 connected to t respective damper elements 2, 3.
  • gears are in engageme with a further gear 11 secured against rotation relative to shaft 12, which serves as a pivot shaft for the damper devic
  • the gears 9-11 are bevelled as illustrated and the pivot shaf 12 extends at an angle of about 90 relative to the axes of t gears 9, 10.
  • the first gear 9 is secured against rotatio relative to a sleeve 13, which protrudes through the casing and is secured against rotation relative to the damper elemen 2.
  • the second gear 10 is secured against rotation relative to shaft 14, which protrudes through a central hole in the gear 1 and extends through the sleeve 13 to a rigid connection to th second damper element 3 at its lower end.
  • the shaft 14 run freely within the sleeve 13 and is preferably radially jour nalled by means of the latter.
  • a holder 16 comprising bearing opening for the shaft 12.
  • a spring 17 acts between th holder 16 and the gear 11 and/or an abutment on the shaft 1 and has the purpose to maintain the gear 11 in engagement wit gears 9, 10. Accordingly, the shaft 12 is displacably journal led in its longitudinal direction relative to holder 16. Th spring 17 may for instance be formed by a screw compressio spring arranged about shaft 12.
  • the shaft 12 may be connected to an operating arm 18 fo operation of damper elements 2, 3.
  • the shaft 12 is rotatable b means of this arm and this rotational movement is transferre from gear 11 to gears 9 and 10 in such a way that the dampe elements 2 and 3 will be pivoted uniformly but in differen directions.
  • the holder 16 may b provided with a scale 19 serving to assist in adjusting the ar 18 so that the damper elements obtain the desired position.
  • a certain adjustment established to be suitable may be defined by means of an indicator member 20, which may be secured in a desired position along the scale and which may operate as a stop for the movement of arm 18.
  • the damper elements 2, 3 are curved in accurate correspondence to the internal surface of the casing 1 so that there is, in the open position of the damper elements, always an equally large distance between the outside of the damper elements and the inside of casing 1.
  • the casing 1 may suitably comprise grooves 21 or other designs for receiving sealing rings intended to provide a tight connection relative to duct pieces connectable to the opposite ends of the casing.
  • each of the damper elements located upstream in the air flow direction lies, in the open position (see fig 5) of the damper elements, generally in a plane forming an angle a with a plane P extending transversely to the casing which is smaller than 30 but larger than 0 . More specifically, said upstream edge 4 lies upstream relative to the plane P, which is drawn out in fig 5 and extends transversely relative to the casing 1 while passing through the pivot axis of the damper elements.
  • the angle a is smaller than 28 but larger than 2°. It is preferred that the angle a is between 17.5 an 27.5 , 20-25 being particularly preferred. The angle a is the embodiment about 22.5 .
  • the closed position of the damp element is indicated with dashed lines. Furthermore, it appea by the dashed double arrow how the portion of the edge 4 whi is mostly spaced from the pivot axis of the damper element moving when operating the damper element from its open to i closed position. It also appears that said portion of t damper element is located at generally the same distance fr the inner wall of the casing 1 in these open and closed pos tions.
  • the pivot angle c of the damp element between the open and closed position is approximate 2 x a.
  • the angle c is in the embodiment smaller than 60
  • the angle c is between 30 and 60 .
  • the most pr ferred is between 40 and 50 , the angle c being in the emb diment about 45 .
  • each of the damp elements are generally located in planes, which between the selves form an angle which is larger than 60 preferably larg than 65°. In the embodiment this angle (a + b) is about 67.5 .
  • the edge 5 of the damper elements which located downstream in the air flow direction will in the op position of the damper elements generally lie in a plane, whi forms an angle with a plane P extending transversely to t longitudinal direction of the casing which is larger than 3 and smaller than 60°. It is preferred that the angle b between 40 and 50°. In the embodiment the angle is about 45°.
  • the sealing members 22 have preferably the character of a strip like slipping sealing, which by slippingly abutting against the inside of the casing seals the space between this inside and the respective damper element in the opened and closed posi ⁇ tions of the damper element as well as in its positions there ⁇ between.
  • Each of the damper elements 2, 3 comprises preferably a sealing member 22 along its entire edge 4 located upstream.
  • the sealing member 22 is of an elastic design, e.g. of rubber or plastic, and secured to the respective damper element in an arbitrary manner, e.g. glueing, screwing, riveting etc.
  • the casing 1 is provided with at least two measuring openings 23, 24, a first 23 of which is adapted to communicate with the interior of casing 1 up-stream of the damper elements 2, 3 whereas the second 24 is adapted to communicate with the interior of the casing downstream of the damper elements.
  • the arrangement of these measuring openings 23, 24 is based upon the notion that for determining flow amounts, flow measuring means of the pressure drop type may be used, wherein the static pressure drop across a restriction device gives a differential pressure which is proportional to an amount of flow.
  • pressure measuring members 25 and 26 may be connecte as indicated diagrammatically in fig 3. Knowing the amount of restriction between the measuring openings 23 and 24 and th pressure differential obtained with the assistance of the pressure measuring members 25, 26, information is accordingl obtained, on basis of which the flow through the casing 1 ma be determined.
  • the damper elements 2, 3 will them selves form said restriction device, i.e. in dependence upo the position of the damper elements a smaller or larg restriction of the flow through the casing is obtained.
  • a smaller or larg restriction of the flow through the casing is obtained.
  • the device is of course preferably such that the sealing memb 22, which is coordinated to at least one of the damper elemen and which is located in the area of the measuring openings 23 24, acts sealingly relative to the casing 1 in the area betwe the measuring openings. Accordingly, there will also in t open position (fig 3) of the damper elements occur a restric tion functioning between the measuring openings 23, 24 due the engagement of the sealing member 22 against the casing i the area between the measuring openings. This restriction i sufficient to provide, by means of the measuring openings 23 24, information about the flow in the casing although t damper elements are parallel to the wall of the casing.
  • the relation flow q/damper opening degree ⁇ for the dampe device according to figs 1-8 is illustrated with the full lin 27 in fig 9.
  • the straight inclined line indicates an idea proportional regulation characteristic.
  • th curve illustrated with the line 27 is relatively close to th ideal proportionality.
  • the regulation characteristics for tw dampers commonly occurring in ventilation arrangements, namel the throttle damper and the iris damper respectively, ar indicated with dashed and dash dotted curves.
  • the known dampers have a considerably worse regulation charac teristic.
  • the damper elements 2 and 3 are each rigidl secured relative to two respective shafts 28, 29 and 30, 31 respectively. These shafts are rotatably received in the casing 1 or in bearings arranged thereon. Each of the shaft pins 28-31 comprises a gear rigidly secured thereto, the gears being in engagement with each other in pairs.
  • One of the shafts, e.g. the one denoted 28, comprises an extensioning forming an operating member 32, which may be rotatably supported relative to a holder 33 attached to the casing 1. By rotating the shaft 28, the damper elements 2, 3 will be pivoted in opposite directions as in the preceding case.
  • damper elements 2, 3 here have edges 4, which in the open positions of the damper elements are located up-stream and which in the planar, spread out condition of the damper ele ⁇ ments do not form any parabola but instead a straight line.
  • the edges 5 of the damper elements 2, 3 located downstream in the open position form in the spread out condi ⁇ tion of the damper elements parabolic archs.
  • the edges 4 are in the open position of the damper elements generally located in a plane extending transversely to the longitudinal axis of the casing 1.
  • the operating arrangement 34 disclosed herein is for the rest of another kind than the one previously described. More speci ⁇ fically, the operating arrangement 34 comprises a rotatable shaft 35, which is rotatably journalled at the casing 1 and/or a holder 36 arranged thereon.
  • An operating member 37 rigidly mounted to the shaft 35 comprises two guides 38, 39, along which follower members 40, 41 are movable on rotation of the operating member 37 by means of the shaft 35.
  • the two follower members 40, 41 are connected to a respective arm 42 and 43, which in its turn is secured against rotation relative to respective shaft 44 and 45.
  • Each of these two shafts 44, 45 connected to one of the damper elements 2, 3.
  • the operating or transmission member 37 has in the embodime the character of a plate and its guides 38, 39 are formed arcuate slots therein, said slots having first ends relative close to the center of the plate and second ends relative close to the periphery of the plate.
  • the follower members 4 41 are formed by pins or projections received in these respe tive slots 38, 39.
  • One 45 of the shafts 44, 45 has the chara ter of a sleeve secured against rotation relative to the damp element 2 whereas the other shaft 44 projects through a preferably is radially journalled in the shaft sleeve 45 a secured against rotation relative to the other damper eleme 3.
  • the shaft sleeve 45 is preferably supported relative to t casing 1 or the holder 36 by means of suitable bearings.
  • the damper elements in this embodiment have generally the sa design as in figs 1-9.
  • the difference consists in the presen of a different type of sealing members 46 between the inside the casing 1 and the damper elements 2, 3. More specificall these sealing members are designed as a ring shaped coll comprising a surface turned inwardly towards the damper el ments, said surface being designed in correspondence to t movement described by points on the edges 4 located upstream on the damper elements on movement of the damper elements from open to closed position and vice versa.
  • the edges of the damper elements located upstream will always be very close to or in slipping engagement against this collar 46 along the entire circumference of the configuration formed by the damper elements in common.
  • edges 4 of the damper elements 2, 3 located upstream could possibly comprise some kind of elastical sealings for slipping engagement against the collar 46 then being generally rigid.
  • the collar 46 could be provided with some kind of elastical coating on its side turned inwardly towards the damper elements, said elastical coating being adapted to be in contact with the edges 4 of the damper elements located upstream.
  • the shape of the annular collar 46 will of course vary along the circumference in correspondence to the path of movement of the edges 4 of the damper elements located upstream.
  • measuring openings 23, 24 are provided and these are here located on either sides of the collar 46, which is tightly connected to the inside of the casing 1.
  • This embodiment corresponds to the one illustrated in fig 15 with the exception that each of the damper elements 2, 3 here are so designed that they in a planar, spread out condition have opposite parabolic archs, which are generally identical.
  • the edges, 4, 5 of the damper elements located upstream and downstream respectively will form angles a and b with the transverse plane P passing through the pivot axis of the damper elements which are equally large.
  • Each of the angles a and b is in the embodiment about 30 , from whic it follows that the angle of pivoting of the damper element between open and closed position is about 60 .
  • the sealing members 22 and 46 may designed in many other ways than those described.
  • One or mo elastical sealing members could for example be attached on t inside of the casing 1 for cooperation with the damper el ments.
  • the inventi by no means is limited to such designs, where the casing 1 ha in cross section, circular, oval or otherwise round shape
  • the casing could be cross-sectionally rectangular otherwise polygonal with damper elements curved in correspo dence thereto and pivotably supported about a common axis alternatively two axes disposed relatively close to each oth in the central area of the casing.
  • each of the damp elements would accordingly have a generally U-shaped curv profile.
  • other modifications are possible within the sco of the invention.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Air-Flow Control Members (AREA)
  • Lift Valve (AREA)

Abstract

Un registre comporte une enveloppe (1) d'acheminement de flux présentant une paroi incurvée en section et deux éléments à registre (2, 3) montés pivotants dans ladite enveloppe. Lesdits éléments sont incurvés généralement au niveau de la paroi de l'enveloppe et agencés pour coopérer de manière à arrêter généralement ensemble, en position fermée, l'écoulement à travers ladite enveloppe. Les deux éléments à registre sont, dans leurs positions ouvertes, situés généralement le long de la paroi de l'enveloppe tout en délimitant entre eux un canal entièrement ouvert.
EP19890907354 1988-06-23 1989-06-22 Registre Withdrawn EP0423169A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE8802363A SE8802363D0 (sv) 1988-06-23 1988-06-23 Anordning vid inregleringsdon for luft
SE8802363 1988-06-23

Publications (1)

Publication Number Publication Date
EP0423169A1 true EP0423169A1 (fr) 1991-04-24

Family

ID=20372714

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19890907354 Withdrawn EP0423169A1 (fr) 1988-06-23 1989-06-22 Registre

Country Status (3)

Country Link
EP (1) EP0423169A1 (fr)
SE (1) SE8802363D0 (fr)
WO (1) WO1989012791A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19822910A1 (de) * 1998-05-22 1999-12-02 Neumann Jens Verschlußelement für Leitungen

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1125766A (fr) * 1954-06-08 1956-11-07 Obturateur à plusieurs parties destiné à obturer des tubes guidant l'eau

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8912791A1 *

Also Published As

Publication number Publication date
WO1989012791A1 (fr) 1989-12-28
SE8802363D0 (sv) 1988-06-23

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