EP0044304A1 - Sound damping in ventilation conduits. - Google Patents

Sound damping in ventilation conduits.

Info

Publication number
EP0044304A1
EP0044304A1 EP80901859A EP80901859A EP0044304A1 EP 0044304 A1 EP0044304 A1 EP 0044304A1 EP 80901859 A EP80901859 A EP 80901859A EP 80901859 A EP80901859 A EP 80901859A EP 0044304 A1 EP0044304 A1 EP 0044304A1
Authority
EP
European Patent Office
Prior art keywords
conduits
slab
connection
transverse
closed
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.)
Granted
Application number
EP80901859A
Other languages
German (de)
French (fr)
Other versions
EP0044304B1 (en
Inventor
Lars Olof Andersson
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.)
Strangbetong AB
Original Assignee
Strangbetong AB
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 Strangbetong AB filed Critical Strangbetong AB
Publication of EP0044304A1 publication Critical patent/EP0044304A1/en
Application granted granted Critical
Publication of EP0044304B1 publication Critical patent/EP0044304B1/en
Expired legal-status Critical Current

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62—Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls specifically with respect to sound only
    • E04B1/84—Sound-absorbing elements
    • 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
    • F24F13/24—Means for preventing or suppressing noise

Definitions

  • This invention relates to arrangement and method in sound damping of ventilating conduits in frame-work elements.
  • Parallel conduits in the direction of the span of prefabricated framework elements are often used for branching off the ventilation system in a building.
  • sons of the conduits in the framework elements are conneced in one end to a feeding conduit, and the air is thereafter passed on through the conduits to exhausting means connected to a conduit somewhere along its length, or at its end.
  • exhausting means connected to a conduit somewhere along its length, or at its end.
  • a transverse connection is established between two separate parallel conduits so that these conduits are connected in series for the ventilating air, which hereby is passed in zigzag through the conduits in the frame-work elements.
  • the invention relates to a construction, which is so formed, that the framework acts as sound damping means for noice from fans and sound, which is transmitted from one room to another via the ventilating piping and the invention also relates to a method for producing said transverse connections between the conduits in the framework.
  • the invention consists of an arrangement where the parallel conduits in the framework are closed in their ends by means of concrete plugs, which normally are casted on the building place after the erection of the framework elements and which conduits have at least one connection which is placed transversely between two conduits and which is placed at that end of the framework elements, which is opposite to the inlet end of the conduits for the ventiiating air.
  • two or more conduits may be connected in series by means of the transverse connection.
  • Fig, 1 shows two embodiments of the invention, where a concrete slab is cut and taken apart in its two parts.
  • Fig. 2 is a perspective view of a concrete slab in a third embodiment of the invention.
  • Fig. 3 is a side view of a concrete slab according to Fig. 2.
  • Fig. 4 is a cross section in the plane of the slab where three of the mentioned embodiments are shown in the form of a complete product.
  • Fig. 1 is thus a perspective view showing a concrete slab 1, and the slab is cut transversely so that a small piece 2 has been parted, whereby the openings of five conduits 3, 4, 5, 6 and 7 are shown, A transverse connection 8 has been opened between the conduits 3 and 4 by that a cavity has been cut down in both conduit 3 and the conduit 4 from the upper side 9 of the slab before the concrete has been set. After that cavity has been cut and after that the concrete has set, the cavi vity is covered in the upper side 9 by means of plastic, a rubber plug or other suitable material. The plug is shown by phantom lines and is denoted by 10. The plug only reaches the upper edge of the conduits 3 and 4 and it is thus seen, that a connection 8 is established between the two conduits 3 and 4 under the plug 10. See also Fig. 3 and the following.
  • FIG. 1 A second embodiment of the transverse connection is also shown in Fig. 1 from which the connection between conduits 5, 6 and 7 can be seen.
  • This connection has been established by that a boring has been drilled transversely to the conduits 5, 6 and 7 and ending in the conduit 5.
  • the boring is parallel to the upper side 9.
  • the boring is plugged between the edge 11 of the slab and the conduit 7 by a plug 10 and this can be done after that the slab has been set by inserting an expander plug or the like in the boring. Concrete or plastic can also be used for this purpose.
  • This embodiment is also shown in Fig. 4 according to what will be described below. It is obvious that according to the two embodiments described any number of conduits can be connected though in the first case it has been described a connection between the two conduits and the second embodiment includes a connection between three conduits.
  • a third embodiment is shown for establishing the connection between the conduits.
  • This is shown by a connection being established between the conduits 3, 4 and 5.
  • the conduits are opening in the the front side 13 of the slab.
  • the connection is formed by that a notch 14 has been made between the conduits 3 and 4 and between the conduits 4 and 5 in the front side 13.
  • the notch is so deep that its cross section area is that of the conduits.
  • the notch 14 is covered by a plate 15 or by other suitable means, see Fig. 3. It can be seen that hereby the notch 14 is closed at the front edge 13 and that thus the connection is made between all the three conduits 3, 4 and 5, see also Fig. 4.
  • Fig. 4 is a cross section along the upper side 9 of the concrete slab 1.
  • Fig. 4 shows how the conduits 3, 4, 5 and 6 are connected so a medium can pass in series through all four conduits.
  • Initially all conduits are opened in the front side 16 of the slab 1 while the oppsite front side 17 has no openings to the conduits.
  • the connection between the conduits 4 and 5 has been established according to the third described embodiment and thus the embodiment, which can be seen from Figs. 2 and 3.
  • a notch has been made in the front side 16 between the conduits 4 and 5 whereby the interconnection 14 is made and the notch has been covered by the plate 15 against the front side
  • transverse connection between two conduits could be established by drilling a bore from the side 18 all the way through the slab whereafter this boring could be plugged between conduits 4 and 5 in the left end of the slab, whereby the medium is passed in series through all four conduits according to the arrows in Fig. 4.
  • the passage for the medium through the conduits can of course follow another path than the one shown in Fig. 4. It is also possible to establish transverse connections between two conduits by that a hole is drilled from a mouth of anyone of the conduits 3-7 and that the drilling is carried out in inclined direction to the longitudinal axis of the conduits and thus into an adjacent conduit.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Architecture (AREA)
  • Structural Engineering (AREA)
  • Civil Engineering (AREA)
  • Electromagnetism (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Building Environments (AREA)
  • Duct Arrangements (AREA)
  • On-Site Construction Work That Accompanies The Preparation And Application Of Concrete (AREA)
  • Pipe Accessories (AREA)

Abstract

De maniere a obtenir un meilleur amortissement sonore du bruit engendre par les ventilateurs, qui se produit dans des systemes de ventilation, il a ete demontre qu'un bon amortissement peut etre obtenu si l'air de ventilation circule dans deux ou plusieurs conduites avant de deboucher dans la piece. A cet effet, une connexion transversale est etablie entre deux conduites separees paralleles de maniere a ce qu'elles soient connectees en serie, pour l'air de ventilation, qui passe ainsi en zigzag au travers des conduites dans les elements de la structure. Le dispositif est forme de telle sorte que la structure joue le role de moyen d'amortissement sonore du bruit provenant des ventilateurs et du bruit qui est transmis d'une chambre a une autre par l'intermediaire des conduites de ventilation. Les conduites paralleles (3, 4, 5, 6) de la structure sont fermees a leurs extremites a l'aide de bouchons en beton, qui normalement sont coules sur le site de l'edifice apres erection des elements de structure, lesquelles conduites possedent au moins une connexion (8) qui est placee transversalement entre deux conduites (3, 4) et qui est placee a l'extremite des elements de structure, a l'oppose de l'extremite d'entree des conduits de l'air de ventilation. De cette maniere deux ou plusieurs conduits peuvent etre connectes en serie au moyen de la connexion transversale.In order to obtain better sound absorption of the noise generated by the fans, which occurs in ventilation systems, it has been shown that good absorption can be obtained if the ventilation air circulates in two or more ducts before lead into the room. For this purpose, a transverse connection is established between two separate pipes parallel so that they are connected in series, for the ventilation air, which thus passes in a zigzag through the pipes in the elements of the structure. The device is shaped in such a way that the structure acts as a sound-absorbing means for noise from the fans and noise which is transmitted from one room to another through the ventilation ducts. The parallel pipes (3, 4, 5, 6) of the structure are closed at their ends with concrete plugs, which normally are poured on the site of the building after erection of the structural elements, which pipes have at least one connection (8) which is placed transversely between two ducts (3, 4) and which is placed at the end of the structural elements, opposite the inlet end of the air ducts of ventilation. In this way two or more conduits can be connected in series by means of the transverse connection.

Description

ARRANGEMENT AND METHOD IN SOUND DAMPING OF CONDUITS FOR VENTILATION IN FRAMEWORK ELEMENTS
This invention relates to arrangement and method in sound damping of ventilating conduits in frame-work elements.
Parallel conduits in the direction of the span of prefabricated framework elements are often used for branching off the ventilation system in a building. Hereby sons of the conduits in the framework elements are conneced in one end to a feeding conduit, and the air is thereafter passed on through the conduits to exhausting means connected to a conduit somewhere along its length, or at its end. In order to achieve a better sound damping of sound from fans, which occurs in ventiiating systems it has been shown that a good damping can be achieved if the ventilating air is circulated in two ormore conduits before being let out in the room. For that purpose, a transverse connection is established between two separate parallel conduits so that these conduits are connected in series for the ventilating air, which hereby is passed in zigzag through the conduits in the frame-work elements.
Thus, the invention relates to a construction, which is so formed, that the framework acts as sound damping means for noice from fans and sound, which is transmitted from one room to another via the ventilating piping and the invention also relates to a method for producing said transverse connections between the conduits in the framework. Thus, the invention consists of an arrangement where the parallel conduits in the framework are closed in their ends by means of concrete plugs, which normally are casted on the building place after the erection of the framework elements and which conduits have at least one connection which is placed transversely between two conduits and which is placed at that end of the framework elements, which is opposite to the inlet end of the conduits for the ventiiating air. Hereby two or more conduits may be connected in series by means of the transverse connection.
The object of the invention is to describe a solution of the above stated problem and the characterizing features of the invention are started in the following claims.
The invention will now be described in connection with the accompanying drawings.
Fig, 1 shows two embodiments of the invention, where a concrete slab is cut and taken apart in its two parts.
Fig. 2 is a perspective view of a concrete slab in a third embodiment of the invention.
Fig. 3 is a side view of a concrete slab according to Fig. 2.
Fig. 4 is a cross section in the plane of the slab where three of the mentioned embodiments are shown in the form of a complete product.
Fig. 1 is thus a perspective view showing a concrete slab 1, and the slab is cut transversely so that a small piece 2 has been parted, whereby the openings of five conduits 3, 4, 5, 6 and 7 are shown, A transverse connection 8 has been opened between the conduits 3 and 4 by that a cavity has been cut down in both conduit 3 and the conduit 4 from the upper side 9 of the slab before the concrete has been set. After that cavity has been cut and after that the concrete has set, the cavi vity is covered in the upper side 9 by means of plastic, a rubber plug or other suitable material. The plug is shown by phantom lines and is denoted by 10. The plug only reaches the upper edge of the conduits 3 and 4 and it is thus seen, that a connection 8 is established between the two conduits 3 and 4 under the plug 10. See also Fig. 3 and the following.
A second embodiment of the transverse connection is also shown in Fig. 1 from which the connection between conduits 5, 6 and 7 can be seen. This connection has been established by that a boring has been drilled transversely to the conduits 5, 6 and 7 and ending in the conduit 5. The boring is parallel to the upper side 9. In order to establish a connection only between the conduits 5, 6 and 7 the boring is plugged between the edge 11 of the slab and the conduit 7 by a plug 10 and this can be done after that the slab has been set by inserting an expander plug or the like in the boring. Concrete or plastic can also be used for this purpose. This embodiment is also shown in Fig. 4 according to what will be described below. It is obvious that according to the two embodiments described any number of conduits can be connected though in the first case it has been described a connection between the two conduits and the second embodiment includes a connection between three conduits.
In Fig. 2 a third embodiment is shown for establishing the connection between the conduits. This is shown by a connection being established between the conduits 3, 4 and 5. In this case the conduits are opening in the the front side 13 of the slab. The connection is formed by that a notch 14 has been made between the conduits 3 and 4 and between the conduits 4 and 5 in the front side 13. The notch is so deep that its cross section area is that of the conduits. After that the notch has been made and the slab has set, the notch 14 is covered by a plate 15 or by other suitable means, see Fig. 3. It can be seen that hereby the notch 14 is closed at the front edge 13 and that thus the connection is made between all the three conduits 3, 4 and 5, see also Fig. 4.
Fig. 4 is a cross section along the upper side 9 of the concrete slab 1. In order to show the invention Fig. 4 shows how the conduits 3, 4, 5 and 6 are connected so a medium can pass in series through all four conduits. Initially all conduits are opened in the front side 16 of the slab 1 while the oppsite front side 17 has no openings to the conduits. Between the conduits 3 and 4, there is a transverse connection 8, which has been formed according to the first described embodiments and thus the cavity 8 is covered in the upper side by a plug or a cover, which can not be seen from Fig. 4. The connection between the conduits 4 and 5 has been established according to the third described embodiment and thus the embodiment, which can be seen from Figs. 2 and 3. Thus, a notch has been made in the front side 16 between the conduits 4 and 5 whereby the interconnection 14 is made and the notch has been covered by the plate 15 against the front side
16. Finally, a transverse connection has been established between the conduits 5 and 6 by drilling a bore from side 18 of the slab, which correspond to the boring from side 11 in Fig. 1. The plug 12 has been inserted in the boring from the long side 18 and thus the left end of the conduits 5 and 6 has been interconnected and the medium is prevented from passing out of the side 18. It is only by way of an example that all three embodiments are shown in Fig. 4. The inventive idea can be. varied in many ways and referring to Fig. 4 it can be seen that the transverse connection between two conduits could be established by drilling a bore from the side 18 all the way through the slab whereafter this boring could be plugged between conduits 4 and 5 in the left end of the slab, whereby the medium is passed in series through all four conduits according to the arrows in Fig. 4. The passage for the medium through the conduits can of course follow another path than the one shown in Fig. 4. It is also possible to establish transverse connections between two conduits by that a hole is drilled from a mouth of anyone of the conduits 3-7 and that the drilling is carried out in inclined direction to the longitudinal axis of the conduits and thus into an adjacent conduit. It is also possible to use other methods for closing the recess forming the transverse connection so that the connection passes through a conduit but is closed to the conduit in question, by that a piece of a pipe having the same diameter as the conduits is inserted in the transverse connection.

Claims

CLAIMS :
1. Arrangement in sound damping of parallelly placed ventilating conduits in framework elements of concrete, characterized in that the sound damping is established in the framework elements by that at least two of adjacent conduits (3,4; 4,5) are closed in the same end and are connected by only one transverse connection (8; 14), which is situated near the end closure.
2. Arrangement according to claim 1, characterized in that three or more pair of conduits are connected two and two by transverse connections so that the conduits are connected in series for passing ventilating air to an exhaust opening.
3. Arrangement according to claim 1 and 2, characterized in that the transverse connection (8; 14) is placed at some distance from the end closures of the conduits and preferably at a distance of 0,5 - 2,0 m.
4. Arrangement according to claim 1, characterized in that a plug of sound damping material, for instance mineral wool, is placed within the area between the end closure of the conduits of concrete and a transverse connection (8; 14).
5. Arrangement according to claim 4, characterized in that the plugs is of sound isolating material and it is a form of a wedge.
6.Method for establishing a bore connection between longitudinal conduits enclosed in a concrete slab when being produced, characterized in that before the con crete is set, at least one cavity is taken out from any of the sides of the slab at least so deep that a connection is established between at least two adja cent conduits and that the connection is closed to the side of the slab by a cover or an adjacent concrete slab.
7. Method according to claim 1, characterized in that the cavity is made from a side of the slab and that a plate is casted in the plane of the side of the slab and thereby covering said cavity.
8. Method according to claim 1, characterized in that transverse connections are drilled from an edge side of the slab and parallel with the side of the slab and transverse to the conduits, whereafter the opening of the drilled connection is closed.
9. Method according to claim 8, characterized in that the transverse connection is closed to one or more of the conduits by a piece of a pipe.
10. Method according to claim 1, characterized in that the transverse connections are taken out from an end side of the slab, where the conduits are opening and through at least one of said openings.
EP80901859A 1979-10-05 1980-10-01 Sound damping in ventilation conduits Expired EP0044304B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE7908293A SE422609B (en) 1979-10-05 1979-10-05 DEVICE AND PROCEDURE FOR SOUND MUTING OF VENTILATION CHANNELS IN BED CLOVER
SE7908293 1979-10-05

Publications (2)

Publication Number Publication Date
EP0044304A1 true EP0044304A1 (en) 1982-01-27
EP0044304B1 EP0044304B1 (en) 1984-03-07

Family

ID=20338990

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80901859A Expired EP0044304B1 (en) 1979-10-05 1980-10-01 Sound damping in ventilation conduits

Country Status (8)

Country Link
EP (1) EP0044304B1 (en)
BE (1) BE888283A (en)
DE (1) DE3066852D1 (en)
DK (1) DK235981A (en)
FI (1) FI68697C (en)
NO (1) NO152947C (en)
SE (1) SE422609B (en)
WO (1) WO1981001026A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5239792A (en) * 1990-01-09 1993-08-31 Teletron Limited Eavesdropping-proof room and sound dampening devices therefor

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US640176A (en) * 1899-02-23 1900-01-02 Heinrich Lehmann Process of producing hollow walls and roofs of cast mortar.
DE800331C (en) * 1949-03-26 1950-10-30 Buderus Eisenwerk Process for improving the thermal insulation properties of precast concrete components such as slabs, stones and the like. Like., with continuous cavities
FR1227466A (en) * 1959-03-13 1960-08-22 hollow reinforced concrete elements and method of assembly thereof
SE349842B (en) * 1970-12-21 1972-10-09 Straengbetong Ab

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8101026A1 *

Also Published As

Publication number Publication date
DK235981A (en) 1981-05-29
EP0044304B1 (en) 1984-03-07
NO152947C (en) 1985-12-18
DE3066852D1 (en) 1984-04-12
NO152947B (en) 1985-09-09
FI811637L (en) 1981-05-27
NO811847L (en) 1981-06-01
BE888283A (en) 1981-07-31
WO1981001026A1 (en) 1981-04-16
SE422609B (en) 1982-03-15
FI68697C (en) 1985-10-10
SE7908293L (en) 1981-04-06
FI68697B (en) 1985-06-28

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