Acoustics – Sound-modifying means – Sound absorbing panels
Patent
1997-05-06
1999-09-28
Dang, Khanh
Acoustics
Sound-modifying means
Sound absorbing panels
181295, E04B 182
Patent
active
059592648
DESCRIPTION:
BRIEF SUMMARY
FIELD AND BACKGROUND OF THE INVENTION
The invention relates to a sound absorber having a bottom portion and a structure portion, there being formed, in the structure portion, hollow chambers which have chamber walls and which are formed like small boxes or cups, and the bottom portion furthermore being joined to the structure portion, for example welded thereto, and the hollow chambers being open on one side.
An absorber of this kind is known, for example, from DE-OS 27 58 041. In the known absorber, the hollow chambers of the structure portion are covered by a planar film as the bottom portion, which film seals air-tight each of the air volumes contained in the individual hollow chambers. Furthermore, there is known, from DE-OS 40 11 705, a further embodiment of a sound absorber of this kind, in which the structure portion is joined only at the edge to the bottom portion. The joiner is provided here by means of an elastic sealing lip. The sound absorber may be manufactured as a whole in this manner by the blow moulding method. Embodiments are also known in which each hollow chamber is joined to the bottom portion, each such hollow chamber, open at the top, being formed however as a Helmholtz resonator. In a sound absorber known from DE-PS 32 33 654, there are likewise formed individual, separate hollow chambers which, however, have at the top side a structuring in the form of a groove.
Moreover, with regard to the state of the art, reference is further made to DE-OS 40 35 177, DE-PS 42 41 518 and DE-GM 92 15 132.
SUMMARY OF THE INVENTION
Starting from the state of the art initially mentioned, an object of the invention is to provide an absorber with a bottom portion and a structure portion, which absorber, with high acoustic effectiveness, also has a sufficient mechanical stability and is nevertheless manufacturable in an economical manner.
A sound absorber of this kind is initially and substantially formed in that, between the bottom portion and the structure portion, in the region of the hollow chambers, there are formed welds between the chamber walls of the structure portion and the bottom portion, that the welds extend in spot or linear form, that all hollow chambers of the absorber, when closed off from the outside, belong to a common air space enclosed between the structure portion and the bottom portion, and that there are formed hollow chambers, whose chamber walls, of substantially like extent in height, are in part welded to the bottom portion and in part directed projectingly towards the bottom portion, an air gap being left between an end face of the chamber wall and the bottom portion. There is also possible a partially integral edge transition between the bottom portion and the structure portion. A transition of this kind makes it possible, for example, to fabricate the sound absorber as a whole from a tube-form blank, preferably by the blow moulding method. In this connection, in further detail, the transition may also be cut off in a subsequent process section. In that, between the chamber walls of the structure portion and the bottom portion, there are provided welds distributed over the surface region of the sound absorber, there results a high stability. On the one hand, by the remaining spaced-apart walls of the structure portion in relation to the bottom portion, and on the other hand, precisely by the interposed welds, buckling is greatly prevented.
In that nonetheless all hollow chambers belong to a common air space enclosed between the structure portion and the carrier portion, there is provided, also acoustically, an advantageous construction. There is produced, by the remaining communicating openings, which are relatively small in cross-section, a noticeable frictional influence on application of sound to the common air space. In an embodiment, it may be provided that the welds extend island-like. While the latter is also preferred, it may also in principle be provided that welds, mainly linear, extend starting from the respective edges up to a central region of the sound ab
REFERENCES:
patent: 4242398 (1980-12-01), Segawa et al.
patent: 4425981 (1984-01-01), Kiesewetter et al.
patent: 5410111 (1995-04-01), Stief et al.
Bruck Eduard
Oetken Joachim
Dang Khanh
Farber Martin A.
LandOfFree
Sound absorber does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Sound absorber, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sound absorber will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-705918