EP0093001A2

EP0093001A2 - Acoustic building blocks

Info

Publication number: EP0093001A2
Application number: EP83302321A
Authority: EP
Inventors: Juval Mantel
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-04-27
Filing date: 1983-04-22
Publication date: 1983-11-02
Also published as: IL65624A0; EP0093001A3; DE3366397D1; EP0093001B1

Abstract

An improved acoustic building block structure for attenuating unwanted vibrations comprising:

A structure section having a front side, a back side oppositely disposed from said front side,
a composite unit having at least two vibration attenuating components, and
said component lying in the path of vibration from front side to the back side.

Description

This invention is concerned with noise attenuating devices and more particularly with acoustic building blocks for use in constructing noise insulated structures.
Presently sound-proof structures such as sound-proof rooms are constructed with sound absorbing materials used in the room itself. Thus, for example, acoustic tiles are placed on the ceiling and/or walls of the room. Carpeting is used in the room for further sound absorption and drapes are used over the windows. Many times for further sound absorption and noise attenuation the walls themselves may be comprised of dense bricks in order to reduce or mute noises transmitted through the bricks themselves. There are means presently available for preventing transmittal or conduction of noises through the walls of the building concerned. For example, it is known to reduce noise conduction by using either thick bricks or dense bricks in combination with a noise absorbing material attached to the inner surfaces of the bricks.
There are no presently available composite building blocks designed to insulate a building from noises by attenuating the noises transmitted through the peripheral surfaces of the building. There is a need for such composite building blocks to soundproof a building at the present time. Presently, multiple materials are assembled together on site. This is time consuming -and costly.
Accordingly it is an object of the present invention to provide an acoustic building block for use in buildings to soundproof structures by attenuating the noises transmitted through the walls of the building itself.
It is an object of the present invention to provide new and improved acoustic building blocks in which the above referred to disadvantages are substantially reduced or overcome and the above referred to devices are substantially provided.
According to the present invention an improved acoustic building-block for attenuating unwanted sonic vibrations is provided, said building block comprising:

a composite unit having at least two different sonic vibration attenuating components.

A feature of the present invention is that the building blocks are comprised of dual complementary blocks each having at least two distinct sonic vibration muting components.
Yet another feature of the present invention provides for such building blocks where one of the components comprises a fibrous (or other) material for sound absorbing and the other component is a highly dense material.
Another feature of the invention comprises building blocks wherein one of the components is a highly dense material or mass concentration while another component comprises a serpentine pathway of brick material, said serpentine pathway elongating the distance travelled by the vibration waves and sound transmitting losses due to changing modes of vibrations in corners and due to reflections in the corners, and hence adding to the attenuation of said waves.
Yet another feature of the invention provides for building blocks comprising a sound absorbing material and a serpentine pathway of a normal brick material.
Yet another feature of the invention provides for composite building blocks wherein one of the components of the building block is a pathway having a length which places it in an anti-resonant frequency mode of the noise frequency being attenuated.
Yet a further feature of the invention comprises an acoustic building block having at least two distinct noise attenuating components wherein one of the components provides at least two opposite going pathways that conduct interfering vibrational waves of the same frequency to thereby cancel out the noises. Thus because of the nature of the pathways the vibrations in the distinct pathway are out of phase.
The operation and utilization of the present invention will be more fully apparent from the description of preferred embodiments taken.in conjunction with the following drawings in which:

Figs. 1-4 are pictorial showings of embodiments of the inventive composite block utilizing at least two different materials and/or configurations of material,
Figs. 5-7 are pictorial drawings of the inventive insulating block arrangement each showing two complementary composite blocks for noise insulation purposes,
Figs. 8, 10, 11 and 13 are sectional showings of embodiments of the invention each including two complementary composite blocks designed for noise insulation purposes, and
Figs. 9 and 12 are views of further dual mode embodiments of a composite block within the scope of the invention.

The embodiment shown in Fig. 1 includes a composite block 11 which is comprised of mortar shells 12 and 13 at each end of the block. Between the mortar shells 12 and 13 is a hollow sectionalized mortar section 14. The shells 12 and 13 are shown to be filled with an acoustical sound absorbing material 16, such as fiber glass, for example. The sectionalized shell 14 comprises a plurality of mortar walls dividing the space within the intermediate section 14 into smaller sub-sections. The walls include horizontal walls 17 and vertical walls 18, for example. The end sections 12 and 13 have baffling apertures therein such as apertures 19 shown in section 12.
The composite sound insulating building block 32 shown in Fig. 2 is comprised of end sections 22 and 23. Each of the end sections 22 and 23 is a solid block of mortar. Between the end sections 22 and 23 is an inner section 24. The inner section is hollow but filled with a sound absorbing material 26. The walls 27 and 28 which run perpendicular to the end sections each contain a dense mass section such as section 29, in addition to having baffled apertures such as aperture 30 therein. The baffled apertures act in the manner of baffle aperture 19 to maximize the distance sound or vibrations must travel on the wall 28.
The composite sound absorbing building block 31 of Fig. 3 is also comprised of a pair of oppositely disposed end sections 32 and 33. In this case the end sections are massive and dense blocks of mortar. An inner section 34 connects the end sections 32 and 33. The section 34 is comprised of a pair of serpentine or folded over wall sections such as, for example, wall section 34a which is perpendicular to and coupled directly to the end section 33. Perpendicular to wall section 34a is a longer section 35 substantially parallel to section 33. Perpendicular to section 35 is a shorter section 36 which connects to another parallel section 37 of substantially the same length as section 35. Section 37 is connected to end section 32 by short perpendicular section 38. This type of fold-over construction is repeated in an opposite serpentine wall starting at section 34b. Each of the long wall sections such as 35 and 37 have a dense mass section integral thereto such as sections 39. In addition the short wall sections such as 34b and 38 have therein baffle apertures such as aperture 40.
Thus the path of vibration through the building block 31 passes first through a heavy mortar section, then along the wall section such as wall section 38 having baffles therein, then along a wall section having a high mass section therein such as section 39. The path continues along a wall section 36 and back along a wall section 37 again having a dense portion 39 and along a baffled wall section 38. Section 36 may also have baffles therein to lengthen the pathway of the vibrations. The lengthened pathway by itself provides acoustical insulation. In addition the denser section- changes the velocity of the acoustical vibrations and accordingly sets up interference patterns. The sections of heavy mass cause sound reflections and thus attenuation. Similarly the length of the serpentine wall 34 and 34b can be adjusted to filter out certain frequencies by setting up interference patterns of the vibrational frequencies in the end section 32 or 33 caused by the transmittals of the vibrations through the serpentine sections. The dimensions of the serpentine sections makes them particularly resonant and anti-resonant to specific frequencies. Selecting the lengths can provide the resonance and anti-resonance desired. Also, by selecting the points at which the sections such as sections 38 are coupled to the end sections, desired interference patterns in the end section can be generated.
The composite acoustical insulating building block 41 shown in Fig. 4 also comprises a pair of end sections 42 and 43. The end sections are joined together by an inner section. The inner section comprises a pair of complementary serpentine walls 44 and 44a. The wall 44 comprises a first comparatively long section 45 normal to end section 43. The wall section 44 continues with a portion 46 that is substantially parallel to section 43. The wall section 46 sharply turns to a wall member 47 substantially normal to wall member 46. Wall member 47 continues as a comparatively long wall member 48 that is normal to wall member 47 and parallel to the end sections. Finally, the serpentine wall is coupled to end member 42 by a wall member 49 that is substantially perpendicular to the end member:
The inner section also comprises the serpentine wall 44a which is complementary to serpentine wall 44. Wall 44a comprises a wall member 49a that is comparatively short and is coupled to and substantially normal to end member 43. Wall member 49a is joined and normal to wall member 48a which is-substantially parallel to the end members. Wall member 48a is joined and normal to wall member 47a which leads to a long wall member 46a that is substantially parallel to the end members. Wall member 46a is joined to end member 42 by a wall member 45a that is substantially normal to the end section 42. The length of the serpentine section here again can be selected to filter out selected frequencies by adjusting the dimensions of the intermediate sections of walls 44 and 44a. In addition the wall members 44 and 44a can set up interfering vibrations in the end member such as end member 42 if the end member 43 is the outer end member and-the end member 42 is the receiving end member.
It should be noted that the end members 42 and 43 can comprise a sandwich having inner and outer walls of normal mortar and an inner section 50 of a different density or mass than the outer portions.
Fig. 5 shows another embodiment of a complementary building block structure. More particularly the building block structure 51 shown in Fig. 5 comprises a pair of complementary building blocks 52 and 53. Each of the building blocks comprises a hollow front section, such as section 54a. Each section 54a has within it sound absorbing material such as the fiber glass material indicated at 59. Each front section 54a has a pair of angle legs at the outer ends thereof leading towards the opposite complementary building block front section. Legs of the building block 53 are shown as legs 55 and 56. Legs on building block 52 are shown as legs 57 and 58. The legs have straight sections perpendicular to the building block section, shown as section 60. An angle section which is substantially perpendicular to section 60 and thus parallel to the front section 54a is shown as section 60a. The complementary building blocks of Fig. 5 provide excellent attenuating sound vibrations. First the sound must pass through the front wall section of the front section 54a and then through the sound absorbing material and subsequently through the massive highly dense leg sections. After it passes through the leg section it then is faced with another hollow section filled with sound absorbing material. Thus the sound is interfered with by the hollow section filled with sound absorbing material and then encounters a highly dense section followed by the hollow sound absorbing material filled section. In between the dense section and the sound absorbing section there is either mortar or an empty space and consequently the sound passes through many different types of sections wherein the vibrations travel at different velocities. This normally attenuates and reflects the sound vibrations.
Fig. 6 is another variation of complementary building blocks. In Fig. 6 the complementary building blocks 61 include building blocks 62a and 62b. The building blocks comprise face sections, shown as 63 and 64, respectively. Each of these sections is normally of high density. Legs extend from each of sections 63 and 64. These legs comprise enfolded portions. For example, leg 65 is in the shape of a hollow T formed by leg sections 68074, wherein sections 68, 69, 72 and 73 are perpendicular to block 64 and the others are parallel thereto.
The building block herein includes the highly dense faces 63 and 64 and the hollow leg portions. The spaces between the hollow leg portions and the complementary block portion may be filled with mortar or left empty. In either case vibrations must pass through different materials causing variations in the velocity of the vibrations therethrough. Also the dimensioning of the "T" sections can be such that certain vibrational frequencies set up interference patterns to further attenuate the vibrations passing through the structure.
The complementary blocks 80 shown in Figure 7 comprise a pair of building blocks 81 and 82. They have main body sections 83 and 84,respectively. They each also have a pair of legs extending from the front ends of said main body section toward the other building block. The legs are hollow structures having a basic trapezoidal configuration in cross-section. The trapezoid comprises a first side such as side 85 perpendicular to the main body section 84 of block 82. Extending perpendicularly to side 85 is a section 86 which is also parallel to the main body section 84. An inwardly slanting section 87 extends back to the main body section. The section 87 meshes with the inwardly slanting section 88 of the trapezoidal-like leg of block 81, for example.
In the block configuration ₈₀ the sound absorption attenuation is caused by, among other things, the highly dense sections 83, 84 leading to the hollow sections.
The sound is attenuated as its velocity changes in going from the highly dense sections to the hollow sections. In addition the linear dimensions of legs 85 and 87, for example, can be selected so as to cause interference at certain frequencies of the vibrations that are transmitted from the main body section 84 into the legs.
Fig. 8 is a configuration of another complementary building block structure shown as 91. Here again the legs, such as leg 92,have a basic trapezoidal configuration in cross-section. The main body section such as 93 on block 94 comprises a dense section 95 followed by a hollow section 96 having a sound absorbing material 97 therein. The legs such as leg 92 is solid in this.case. It is a portion of the main body section 93 that is hollow in this case and may be filled with the sound absorbing material.
_Fig. 9 shows a complementary building block 101 that is different than the previous complementary building blocks in that the space between the complementary angle sections 103, 104 of blocks 105a, 105b has resilient material therein such as, for example, rubber- shown as 102, Here again each of the blocks such as block ₁₀₅a has a main body section 106, which is hollow and defined by the longitudinal walls 107 and 108₎surrounding the hollow portion 109 which may be filled with a sound absorbing material 110. The side walls of the horizontal section are shown as side walls 111 and 112. The side walls extend beyond the longitudinal defining wall 108. The meshing section is coupled to wall 108 by a pair of perpendicular walls 113 and 114. The perpendicular walls ₁₁₃ and 114 are coupled to a long wall section 116. Long wall section 116 has a pair of angle sections 117 and 118 extending therefrom. The angle sections are the meshing portions of the building block and they mesh with complementary portions on similar building blocks.
In the arrangement of Fig. 9 the sound attenuation is caused by, among other things, the changes of velocity caused by the different dimensions of each of the parts or the building blocks. The sound travels by conduction through the perpendicular wall sections 113 and 114. The vibrations also travel by convection through the hollow portion defined by the walls 113, 114 and 116. However the sound velocity changes and is refracted. In addition the dimensioning can be such as to cause interference to certain vibrational frequencies on the vibrations that are transmitted by conduction. The resilient material between the complementary structures adds to the attenuation because of the variations of velocity in the material by the sound absorbing qualities of the elastic material and also by the dimensioning of the conductive path through the material.
Fig. 10 is another complementary building block structure 120. Structure 120 comprises blocks 121 and 122 which are structured to be complementary and mesh with one another. In this case blocks 121 and 122,each comprising a heavy front section such as section 123 and an angled wall section extending therefrom comprising a first wall perpendicular to the main front section 123 such as wall 124. Wall 124 extends to a longitudinal wall 126 that is parallel to'the main body section of block 121. Between the main section 123 and the longitudinal parallel wall section 126 is the corresponding longitudinal wall section 126a of complementary block 122. Also between the main body section 123 and the complementary wall section 126a is a sound absorbing material 128. Similarly there is sound absorbing material 129 between the walls 126 and 126a, and like material 130 between the main section 122a of block 122 and wall 126.
Thus the structure 121 has extensive use of sound absorbing material, including sound absorbing material 131 along wall 124 and along wall 132 which joins section 122a to wall 126a, for example. The sound must pass through either the long wall sections and then some sound absorbing material or a sound absorbing material wall section, sound absorbing material and the main body of the other complementary block.
The embodiment of Fig. 11 also shows a pair of complementary building blocks, comprising building blocks 132a and 132b. Each of these complementary building blocks comprises a main body section 133 and a complementary "_T" section shown generally as 134. The complementary "T" section comprises a stem portion 136 which is perpendicular to the main body section and a cross-section 137. Surrounding the "T" section in the space between the "T" section and the main body section there is sound absorbing material 138. Thus when the blocks are meshed together in the complementary fashion the vibrations must travel through the main section which is comparatively dense, be conducted through the stem portion and then to the cross-section and through sound absorbing material to the main body section. Convectionwise the sound goes from the main body section and the sound absorbing material through the space between sound absorbing material to the cross-section of the complementary brick and then again through sound absorbing material section, sound absorbing material and a dense body section.
Fig. 12 is a variation of the basic building blocks shown in Fig. 11. Here the building block 140 is shown as having a main body section centrally located such as main body section 141. Extending from both sides thereof are the "T" sections shown generally as 142 and 143. Each of the "T" sections comprises a stem 144, which is perpendicular to the main body section, and a cross-section 146 which is parallel to the main body sections. Between the cross-section and the main body section there is space which may be filled with sound absorbing material, such as sound absorbing material 147.
The complementary building block configuration of Fig. 13 shown in the embodiment 150 comprises a first building block 151a and a complementary building block 15_1b. Each of the building blocks 151a and 151b comprises the same component parts. Building block 151a comprises a main body section 152 and a complementary section 153 shaped as a characterized "L". The longitudinal portion 154 of the "L" is perpendicular in cross-section to the main body section 152. Extending perpendicular to section 154 is the base 155 of the "L" which is substantially parallel to main body section 152. The characterized "L" shape is derived from a section 156 extending toward the main body section from the end of the base section 155. The space between the complementary portion may be filled with a sound absorbing material 157. Thus here the sound must travel through the dense main body section and be conducted through the characterized "L" section, then through the hollow space or sound absorbing material.
Thus a plurality of different types of composite building blocks are described herein. Each of the building blocks described contains at least two different composite sound attenuating components,wherein the conduction path is such that the vibrational frequencies being attenuated pass through both of said components. Basically attenuation is accomplished by

(1) increasing the length of the path,
(2) providing materials of different relative densities or masses to thereby cause reflection of the vibrational frequencies as the vibrations are conducted through the block,
(3) providing losses in corners by the changing vibration modes at the corners,
(4) providing passage holes and stopping layers with sound absorbing materials in the paths,
(3) selecting lengths of travel and causing the waves or vibrational frequencies to split such that interference patterns are set up, and
(4) selecting lengths and dimensional characteristics such that anti-resonant nodes are set up.

Both the interference patterns and the anti-resonant nodes are designed to cancel at least some of the vibrational frequencies that the composite building block is designed to attenuate. In some of the embodiments dual composite blocks are used which are designed to cooperate with each other to further attenuate particular noise frequencies.
Accordingly what has been described herein are acoustic building blocks for use in building soundproof structures by attenuating particular noises that would normally be transmitted through the walls of the structure itself.
While the principles of the invention have been described above in connection with specific apparatus and applications, it is to be understood that this description is made by way of example only and not as a limitation on the scope of the invention.

Claims

1. An improved acoustic building block structure for attenuating unwanted vibrations comprising:

a structure section having a front side, a back side oppositely disposed from said front side,

a composite unit having at least two vibration attenuating components, and

said component lying in the path of vibration from front side to the back side.

2. A structure as recited in Claim 1 wherein said building block is comprised of dual complementary blocks each having at least two distinct vibration attenuating components.

3. A structure as recited in any of Claims 1 and 2 wherein one of the components is a highly dense material providing a large mass.

4. A structure as recited in Claim 3 wherein the other distinct vibration attenuating component comprises an elongated conduction path through said building block.

5. A structure as recited in Claim 4 wherein said elongated path comprises a serpentine section of mortar.

6. A structure as recited in Claim 4 wherein said other vibration attenuating component comprises a pathway which splits the noise and later joins the noise in an interfering pattern.

7. A structure as recited in Claim 5 wherein the other vibration attenuating component comprises a pathway having dimensions to provide an anti-resonant node for interfering with the original noise frequency.

8. A structure as recited in Claim 3 wherein said dual blocks are separated from each other by a sound absorbing material and wherein any hollow spaces in the blocks are filled with sound absorbing material.