Vibration attenuation apparatus and method

Abstract

A vibration attenuation apparatus (10), for supporting a lamina (11), comprises a contact member (12) for contacting from underneath, and thereby supporting, a lamina (11); at least one, first resiliently deformable member (13); and a further member (14) for supporting the first resiliently deformable member (13). The contact member (12) and the further member (14) engage the first resiliently deformable member (13) at mutually laterally spaced locations whereby longitudinal wave vibrational energy received at the contact member (12) from a supported lamina (11) is transmitted through and along a length of the first resiliently deformable member (13) towards the further member (14) with conversion to transverse wave form such that the first resiliently deformable member (13) causes attenuation of the vibrational energy.

Description

[0001] VIBRATION ATTENUATION APPARATUS AND METHOD

[0002] The invention relates to vibration attenuation apparatus and an associated method. The invention is of particular utility when it is required to attenuate vibrational energy in a floor or similar laminar structure. The invention also relates to a method of attenuating energy in a lamina; and a lamina supported by one or more example of attenuation apparatus as defined herein.

[0003] As is well known, building floors and similar laminar elements often are subjected to vibrations. These could arise for example because of the operation of powered machines standing on or in proximity to a floor; the operations of an office, which generate the sounds of movements of personnel, their conversations and other activities; in residential accommodation such as apartment blocks and hotels where sound such as conversation noise, the vibrations of a washing machine, music played via a hifi system or the audio output of a television often transmits via a floor to concrete members and thence to other storeys of the building; and in leisure / recreational settings such as a music venue or when a gymnasium or another exercise facility is located beneath or above a residential or office storey of a building.

[0004] Floor noise moreover can arise in a number of other ways than those identified.

[0005] It frequently is strongly undesirable for noise to propagate over any distance in a floor since this can cause unpleasant or stressful harmonic vibrations; and / or the vibrational energy can transmit to locations where it is not intended to be audible (or indeed it may be positively harmful for it to be audible, as may be the case in a hospital or care facility, a hotel spa, a recording studio, rehearsal studio or audiometry laboratory).

[0006] Attempts have been made in the prior art to attenuate vibrational energy of the kinds outlined. However these usually are somewhat crude solutions consisting of sheets of elastomeric material (that often is referred to as "underlay") installed as a layer, of a floor construction, that typically underlies an uppermost layer such as a carpet or floor tiles.

[0007] Underlay usually is successful only to attenuate a limited range of frequencies of vibration. Moreover it can be inconvenient to install, especially in rooms the "footprints" of which are irregular shapes and rooms in which the floor height is not constant across the whole floor. In very large rooms it also can be particularly difficult to install underlay neatly, and often it is necessary to define joints between adjacent lengths of the underlay material. The joints can overlap and when this happens unsightly, and potentially dangerous, bulges can arise in the uppermost flooring layer. If this is a carpet or linoleum layer the overlapping sections of underlay can cause premature wear of the topmost layer.

[0008] If on the other hand underlay is lain with gaps between adjacent sections then its vibration attenuation effect may be compromised; and unsightly or dangerous recesses may be formed in a topmost flooring layer.

[0009] Moreover, as is explained further herein, the vibrational mode experienced by underlay installed as part of a floor is longitudinal vibration. This sometimes is also referred to as compressional vibration. Such vibration causes deformation of the material of the underlay but in many instances the underlay is not able fully to attenuate the compressional waves. Consequently it is believed that the deformation that arises in underlay can become transmitted, as further longitudinal vibrational waves, to cause resonance of objects with which the underlay is in contact. In other words, underlay is not as effective at attenuating longitudinal vibrations as users would like.

[0010] As an alternative to simple, passive attenuation means such as underlay it is known to add active damping apparatus beneath a rigid floor lamina, in a void between the lamina and a further layer of the floor construction such as a concrete screed or lintel. Such means may be effective in attenuating vibrational energy in the laminar floor layer and preventing its transmission; and the attenuators may be easier to install than underlay in rooms of irregular shapes or having height variations from place to place. However such vibration attenuators require power supplies which are time-consuming to install; and they often are expensive to purchase. This may make them unacceptable in for example an apartment block in which noise attenuation must be achieved within a limited budget. Moreover the "carbon footprint" of an attenuator that relies on a power supply and / or batteries to operate may be unacceptable.

[0011] Hence there is a need in the art for apparatus that effectively attenuates vibrational energy, in a lamina such as a floor element, in a range of frequencies, at moderate cost and in a manner that readily accommodates uneven floor levels and irregular room shapes.

[0012] According to the invention in a broad aspect there is provided vibration attenuation apparatus, for supporting a lamina, comprising a contact member for contacting from underneath, and thereby supporting, a lamina; at least one, first resiliently deformable member; and a further member for supporting the first resiliently deformable member, the contact member and the further member engaging the first resiliently deformable member at mutually laterally spaced locations whereby longitudinal wave vibrational energy received at the contact member from a supported lamina is transmitted through and along a length of the first resiliently deformable member towards the further member such that the first resiliently deformable member causes attenuation of the vibrational energy. During such transmission along the length of the resiliently deformable member conversion of longitudinal vibrational energy to transverse wave form may occur.

[0013] Such apparatus is a passive device that, advantageously, does not require a power supply. Hence it is ready for use in the as-manufactured condition and there is no need to install any ancillary parts such as power cables, transformers or batteries.

[0014] The apparatus may be manufactured in a range of sizes, especially a range of heights, and this may be of benefit in accommodating unlevel floors. Using further means described below the apparatus may be made capable of attenuating vibrational energy in a range of frequencies.

[0015] The apparatus may be very rapidly installed in e.g. a floor void. In the most straightforward method of installing the apparatus it is simply placed on a lintel, screed or similar lowermost layer in the void and the remainder of the floor (i.e. a laminar uppermost layer) installed on top of and resting on the contact member of the apparatus. Hence deployment of the apparatus may be achieved very quickly and economically, and this helps to contain the costs of providing sound attenuation in a floor. In practice plural examples of the apparatus would be installed e.g. at regularly or irregularly spaced intervals in order to provide support and attenuation in a substantial percentage of the area of a floor lamina. This aspect is explained in further detail herein.

[0016] The lamina may simply rest on the contact member or it may be secured in place, using one or more fasteners and / or an adhesive material.

[0017] The mode of operation of the apparatus involves as indicated the conversion in the first resiliently deformable member of longitudinal vibrational energy to a transverse wave form. This gives rise to vibration of molecules of the material of the first resiliently deformable member and hence to a heat conversion that attenuates the vibrational energy. The use of one or more resi liently deformable members provides a useable quantity of vibration-attenuating material in a convenient form that in contrast to e.g. underlay does not occupy a large area underneath a floor and yet is provided in a sufficient amount that at least largely complete attenuation may occur. Consequently the problem of transmission of longitudinal vibrational energy as may occur in underlay may be avoided in the apparatus disclosed herein.

[0018] A further advantage of the apparatus as disclosed herein is that it assists a building to comply with a "Life Cycle Assessment" (LCA) requirement or regulation. In this regard many countries now require construction companies and similar entities to submit to LCA audits or to declare LCA compliance. Composite flooring materials including underlay may not readily satisfy the relevant LCA rules. The apparatus of the invention on the other hand permits simplification of the flooring layer, with the result it is more likely to meet an LCA standard.

[0019] The apparatus itself may be made from robust, long-lasting materials. This together with its passive operational mode means the apparatus is highly likely to be re-useable when a floor is dismantled at the end of the life of a building or during an interior refit. This also assists with LCA compliance and more generally renders the apparatus of minimal environmental impact.

[0020] In preferred embodiments the apparatus includes a plurality of the first resiliently deformable members, the contact member and the further member contacting each said first resiliently deformable member at mutually laterally spaced locations whereby longitudinal wave vibrational energy received at the contact member from a supported lamina is transmitted through and along a length of each first resiliently deformable member towards the further member with conversion to transverse wave form such that the first resiliently deformable members cause attenuation of the vibrational energy.

[0021] Among other benefits this construction increases, compared with a single first resiliently deformable member, the volume of material in which attenuation of vibrational energy may take place; it allows supporting of the contact member on the first resiliently deformable members at plural locations, thereby increasing the stability of the apparatus; and it allows for "tuning" of the apparatus to attenuate vibrational energy in a range of frequencies. The last-mentioned effect may be achieved for example by making the plurality of first resiliently deformable members from differing materials such as different densities of an elastomeric material, or indeed mutually distinct materials. Widening of the range of frequencies absorbed also may be achieved for example by including a plurality of the first resiliently deformable members of differing dimensions such that their natural frequencies differ from one such member to the next. Also it is possible to pre-stress one or more of the resiliently deformable members, in ways as exemplified herein, in order to tune individual resiliently deformable members to absorb energy in chosen frequency bands.

[0022] Preferably the or each first resiliently deformable member lies or extends below the contact member. Further preferably the contact member includes a planar upper surface for supporting a lamina and the apparatus further includes at least one downwardly extending protrusion connecting the contact member and one or more of the first resiliently deformable members at a first lateral location on the or each respective first resiliently deformable member.

[0023] This arrangement allows the apparatus to have a vertical extent that for example may be dimensioned to fit into the void beneath a floor. Moreover a construction that extends vertically means that the mass of the lamina may act downwardly to ensure good coupling of vibrational energy to the first resiliently deformable member(s) and thereby maximise the amount of energy that is attenuated.

[0024] Furthermore the further member optionally may lie below the or each first resiliently deformable member and the apparatus may include at least one upwardly extending protrusion connecting the further member and one or more of the first resiliently deformable members each at a second lateral location on the respective first resiliently deformable member that is laterally spaced along the first resiliently deformable member from the first lateral location.

[0025] This arrangement of the parts of the apparatus also permits it to have a vertical extent that may be chosen to fit in to a particular depth of floor void; and further assists to ensure good energy coupling in the device.

[0026] The apparatus optionally may include an additional layer including at least one second resiliently deformable member and a base member, the further member and the base member contacting the second resiliently deformable member at mutually laterally spaced locations whereby longitudinal wave vibrational energy received at the further member is transmitted through and along a length of the second resiliently deformable member towards the base member with conversion to transverse wave form such that the second resiliently deformable member causes further attenuation of the vibrational energy.

[0027] The presence of an additional layer of this kind may assist to provide secondary attenuation of vibrational energy and / or may permit tuning of the device to attenuate energy in a wider range of frequencies than might otherwise be the case. Such tuning may be achieved for example through choice of the precise material, dimensions and / or shapes of the second resiliently deformable member(s).

[0028] Preferred embodiments of the invention may include a plurality of the second resiliently deformable members, the further member and the base member contacting each said second resiliently deformable member at mutually laterally spaced locations whereby longitudinal wave vibrational energy received at the further member is transmitted through and along a length of each second resiliently deformable member towards the base member with conversion to transverse wave form such that the second resiliently deformable members cause further attenuation of the vibrational energy.

[0029] Advantages of a plurality of the second resiliently deformable members are similar to the advantages of a plurality of the first resiliently deformable members as explained above.

[0030] Conveniently the or each second resiliently deformable member lies or extends below the further member, the apparatus further may include at least one downwardly extending protrusion connecting the further member and one or more of the second resiliently deformable members each at a first lateral location on the respective second resiliently deformable member and the apparatus further may include at least one upwardly extending protrusion connecting the base member and one or more of the second resiliently deformable members each at a second lateral location on the respective second resiliently deformable member that is laterally spaced from the first lateral location.

[0031] Advantages of such a vertically extending additional layer construction are similar to those explained above.

[0032] Preferably the apparatus includes a pivot joint interconnecting (a) the contact member, or (b) one or more additional member engaging the contact member, and the resiliently deformable member whereby to constrain the number of degrees of freedom of the contact member and the resiliently deformable member one relative to the other.

[0033] Such a feature may permit the various layers to move relative to one another while advantageously adding to the stability of the apparatus.

[0034] Further optionally the apparatus may include one or more limit stop that is secured relative to the further member and acts during operation of the apparatus to limit movement of the contact member and the resiliently deformable member one relative to the other. This feature may for example prevent straining of the resiliently deformable members beyond their elastic limits. In turn therefore it enhances the longevity of the apparatus.

[0035] The contact member, the one or more first resiliently deformable member, the one or more second resiliently deformable member, the further member and the base member optionally may be arranged to define an oscillation loop around which longitudinal vibrational energy may propagate with transmission along at least part of at least one said first resiliently deformable member and along at least part of at least one said second resiliently deformable member, with attenuation of vibrational energy and at least one transformation between longitudinal and transverse vibrational wave forms during such propagation.

[0036] Such an arrangement of the parts of the apparatus beneficially maximises the attenuation of vibrational energy.

[0037] In potentially all the embodiments defined heretofore the apparatus may include one or more mounting, for one or more said first or second resiliently deformable member, the length of which is adjustable so as to permit adjustment of the position of the respective resiliently deformable member relative to the remainder of the apparatus. This allows adjustment of pressure applied e.g. as a preload by the resiliently deformable member(s) and / or frequency tuning of the apparatus.

[0038] Further preferably the at least one resiliently deformable member optionally is or includes a layer of resiliently deformable material; the contact member is a laminar member and the apparatus includes protruding downwardly between the laminar member and the layer of resiliently deformable material a series of contact member protrusions that contact an upper surface of the layer at a series of mutually laterally spaced upper surface locations; the further member is a laminar member and the apparatus includes protruding upwardly therefrom a series of further member protrusions that contact a lower surface of the layer of resiliently deformable material at a series of mutually laterally spaced lower surface locations, the mutually laterally lower surface locations also each being spaced laterally from the mutually laterally spaced upper surface locations.

[0039] This embodiment is advantageously simple in construction.

[0040] At least two of the contact member protrusions and at least two of the further member protrusions may be provided in a practical version of this embodiment. The embodiment is a straightforward construction that readily may be made e.g. using continuous production techniques. Sheets or rolls of the apparatus may be produced. These may be particularly convenient for the construction industry to store, transport and use.

[0041] Preferably each contact member protrusion is elongate, extends transversely from one side of the contact member to the other, tapers in a protrusion width direction along its length and protrudes downwardly to a varying extent along its length. Similarly each further member protrusion preferably is elongate, extends transversely from one side of the further member to the other, tapers in a protrusion width direction along its length and protrudes upwardly to a varying extent along its length. Such features of the contact member and such features of the further members may in embodiments all be provided in combination with one another. Equally only a selection of the listed features may be provided. As used herein a "selection" may in any given case include only a single one of the listed features, which individually or in combination assist to maximise the range of frequencies attenuated by the apparatus.

[0042] The invention further resides in a method of attenuating longitudinal wave vibration in a lamina, the method comprising causing longitudinal vibrational energy in the lamina to transmit to a contact member supporting the lamina from underneath, and thence to a first location in at least one resiliently deformable member; causing a further member to engage and support the resiliently deformable member at a second location that is laterally spaced from the first location; and causing the vibrational energy to transmit along a length of the resiliently deformable member towards the further member and convert, with attenuation, to transverse wave form.

[0043] Such a method advantageously may be put into effect using vibration attenuation apparatus as defined herein. In the method the step of causing the vibrational energy to transmit with attenuation along a length of the resiliently deformable member optionally may include conversion of vibrational energy to transverse wave form.

[0044] Preferably the method includes causing or permitting pivoting connection between the contact member and the at least one resiliently deformable member whereby to constrain the number of degrees of freedom of the contact member and the resiliently deformable member one relative to the other. Such a feature reduces the number of degrees of freedom of the parts of the apparatus relative to one another and promotes movement of the parts in a manner attenuating vibrational energy.

[0045] The method also optionally may include causing a limit stop, that is fixed relative to the further member, to limit movement of the contact member and the resiliently deformable member one relative to the other. Advantages of this aspect of operation of the apparatus are as set out above.

[0046] The invention further extends to a lamina (such as but not limited to a layer of a floor) that is supported by one or more apparatus as defined herein and / or in which attenuation of vibrational energy occurs in accordance with the method defined herein.

[0047] Such a lamina optionally may be supported on a plurality of the apparatuses that are spaced apart from one another beneath the lamina. When the lamina is so supported preferably the apparatuses are spaced apart at least in the plane of the underside of the lamina in a regular pattern.

[0048] The invention is applicable in a wide range of environments and situations, including (but not limited to) those listed herein.

[0049] There now follows a description of preferred embodiments of the invention, by way of non-limiting example, with reference being made to the accompanying drawings in which :

[0050] Figure 1 is a schematic, side elevational view of a simple form of vibration attenuation apparatus according to the invention, including only a single attenuation layer;

[0051] Figure 2 is a schematic, side elevational view of a more complex embodiment including two layers of vibration-attenuating components; Figure 3 is a schematic, side elevational view of another embodiment that includes two layers of vibration-attenuating parts;

[0052] Figure 4 is a schematic representation of an embodiment including three layers of vibration-attenuating parts;

[0053] Figure 5 shows an embodiment that is similar to the Figure 4 embodiment and illustrates how vibrational energy may propagate around one or more transmission loops defined by the apparatus, while being attenuated;

[0054] Figures 6 and 7 show further embodiments in schematic form;

[0055] Figure 8 is a front elevational view of an embodiment in which the positioning of and pressure applied by a resiliently deformable member is adjustable;

[0056] Figure 9 is a side elevational view of the Figure 8 apparatus;

[0057] Figure 10 is a side elevational view of a variant on the Figure 8 embodiment;

[0058] Figure 11 shows in perspective view a practical version of apparatus, according to the invention, that is similar to the embodiment shown for example in Figure 2;

[0059] Figure 12 shows in side elevational view a further embodiment of the invention in which a single layer of vibration-attenuating parts is provided; and

[0060] Figure 13 shows a variant on the Figure 12 arrangement in which there are two layers of vibration-attenuating parts and the construction is elongated in order to provide attenuation over a length of flooring.

[0061] Referring to the drawings, and initially to Figure 1, a vibration attenuation apparatus 10 for supporting a lamina 11 such as a floor board or other flooring member in a simple form comprises a rigid contact member 12, a first, resiliently deformable member 13, and at least one rigid further member 14 for supporting the first resiliently deformable member 13.

[0062] In the embodiment shown the contact member 12 is an essentially flat, plate-like element that is intended to contact the lamina 11 from underneath, i.e. below the level of a floor. The remainder of the apparatus 10 lies below the contact member 12, so the apparatus would not be visible as long as the floor, etc., defining lamina 11 is opaque.

[0063] The contact member engages the underside of the lamina (floor etc.) 11 and supports it. Consequently any longitudinal wave form vibration occurring in the lamina 11 becomes transmitted to the contact member 12.

[0064] The first resiliently deformable member 13 is supported, and hence engaged, by the further member 14, which in the illustrated embodiment takes the form of a metal (or other rigid material) upright 16. A bracket 17, that also is formed from a rigid material such as a metal, firmly interconnects one end (which is the widest part) of the resiliently deformable member 13 and the upright 16 a short distance from the free, upper end of the latter.

[0065] The first resiliently deformable member 13 is in the illustrated embodiment formed as a cone of a resiliently deformable material such as an elastomer, and in particular a synthetic or natural rubber or rubber composite. Other shapes and forms of the resiliently deformable member however are possible within the scope of the disclosure; and moreover the member 13 may be formed from a range of materials as would occur to the person of skill in the art.

[0066] The upright 16 at its lowermost end terminates in a base member 19 that rests on or is secured to a rigid member such as a concrete (or other rigid material) lintel, beam, board, screed or similar feature represented schematically by numeral 19a.

[0067] The contact member 12 engages the first, resiliently deformable member by way of a downwardly projecting engagement member 18 the lowermost end of which presses into the opposite (narrowest) end of the resiliently deformable member 13 to that at which bracket 17 is secured.

[0068] Although not shown in Figure 1 the apparatus 10 typically would include one or more further features that retain the contact member 12 and engagement member 18 relative to the remainder of the parts of the apparatus 10, while permitting limited movement of the parts as described below.

[0069] When vibration occurs in the lamina 11, for example by way of one or more of the causes listed herein, the rigidity of the material of the floor means that this is likely to be predominantly or entirely of a longitudinal wave form. Such vibrational energy is transmitted from the material of the lamina 11 to the contact member and thence, via the downwardly projecting engagement member 18, to the point (narrowest) end of the first resiliently deformable member 13. This is made possible by the (limited) ability of the contact member 12 and engagement member 18 to move relative to the remainder of the apparatus 10.

[0070] The energy of vibration then passes to the material of the resiliently deformable member. At this time partly because the material of the member 13 is resiliently deformable and partly because the lateral spacings of the connecting parts of the apparatus causes the vibrational energy to travel along the length of the member 13, the vibrational waveform transmits in the resiliently deformable member 13 in a manner that prevents transmission of the energy as longitudinal waves.

[0071] In this regard the elements of the apparatus may be thought of as defining a series of laterally adjacent, vertically extending cells or units. The construction of the apparatus in causing the energy to transmit laterally causes the energy to pass from one adjacent cell to the next, with energy dissipation occurring as a result of motion of the molecules of the resiliently deformable member 13. As a result transmission of the energy from the top to the bottom of the apparatus, as would arise in vertically arranged layers of a floor that does not include the apparatus, is significantly reduced so that in practice only minimal vibration may be detected for example at the level of the lintel 19a.

[0072] This causes movement of the molecules of the resiliently deformable member 13 relative to one another, with the result that the vibrational energy becomes attenuated through conversion primarily to heat.

[0073] At the same time, propagation of the vibrational energy in the resiliently deformable member 13 by reason of its tapered (conical) shape causes the energy to be spread among increasing numbers of molecules of the resiliently deformable material. This reduces the concentration of energy such that in combination with the attenuation effect mentioned above the vibration is barely detectable, or not detectable at all, at the bracket 17. The bracket 17, further member 16 and lintel etc. 19a serve essentially a supporting function. As a result of attenuation of the vibrational energy any element in contact with the lintel etc. 19a does not experience the vibration occurring in the lamina 11.

[0074] Underlay, as is used in prior art installations, is compressed over most if not all of its surface area through contact by the supported lamina. In contrast, in the apparatus disclosed herein the resiliently deformable member(s) 13 is / are unconstrained over most of their volumes. As a result deformation of the molecules of the member(s) 13 may occur more readily and to a greater extent than in underlay or a similarly constrained medium. This in turn enhances the vibration-attenuating effect of the apparatus.

[0075] The apparatus 10 may be manufactured as a module that can be installed under a floor during its construction. In practice a plurality of the apparatuses are likely to be provided at spaced locations below the lamina 11 in order to provide even support and to attenuate vibrations that arise at localised points. However the apparatus may just as readily be constructed from a kit that is assembled and installed in situ.

[0076] An optional feature of the apparatus 10 of Figure 1 is a movement limit stop 21. This takes the form of a rigid (e.g. metal) protuberance that is firmly fixed to the further member 14, the base member 19 or the lintel etc. 19a. The limit stop 21 prevents the resiliently deformable member 13 from deforming excessively, e.g. beyond its elastic limit as may otherwise occur as a result of loading of the lamina 11.

[0077] The limit stop may take a wide variety of forms as would occur to the person of skill in the art.

[0078] Figure 1 omits a small number of features such as fastenings as would normally be provided in the apparatus 10 in order to prevent separation and potential loss of the parts. Such features may readily be envisaged and need not be described herein.

[0079] In Figure 1 the apparatus 10 is shown as a discrete, self-contained device but in alternative embodiments it may be formed as part of or attached to further apparatus. As an example in this regard the upright 16 may be for example a side wall or partition wall of a room, such that the remainder of the apparatus 10 is formed integrally therewith. As a further variant a side wall or partition wall may be of an essentially conventional construction, and an upright 16 of apparatus 10 secured thereto using e.g. one or more fasteners and / or an adhesive compound.

[0080] These versions of the apparatus 10 may be of benefit when for example it is desired to support and attenuate vibrations in a floor lamina 11 at or closely adjacent one or more lateral edges of a floor lamina and / or a room. In such a situation there may not be sufficient space to position a free-standing embodiment of the apparatus 10 in a desired location. Forming the apparatus integrally with, or such that it can be secured to, a wall may advantageously address this requirement.

[0081] It also is possible to consider a floor lamina 11 that is supported on a plurality of the apparatuses 10 with a clearance around its lateral periphery so that it does not contact, and hence is isolated from, a side wall of the room in which the installation is constructed. This also is expected to minimise the transmission of vibrations, via the side wall, the transmission path of which might otherwise bypass the apparatus 10. Combinations of arrangements including peripheral clearances and apparatuses that are integral with or secured to a wall are also possible.

[0082] Variations, as described above, including attachment to or integral forming with a wall and / or one or more peripheral clearances providing spacing also may optionally be implemented in the other embodiments described herein. As needed the further embodiments may be modified, as will occur to the person of skill in the art, in order to permit such integral forming, attachment and / or spacing.

[0083] The embodiment of Figure 1 defines a single layer of vibration-attenuating parts constituted primarily by the single resiliently deformable member 13. Figure 2 shows a variant 10a in which plural resiliently deformable members are formed into two layers of vibration-attenuating parts.

[0084] In Figure 2 a contact member 12 that can be, but need not be, similar to contact member 12 of Figure 1 in use of the apparatus 10a lies beneath, and supports from below, a lamina such as a floor or similar feature. The lamina is not visible in Figure 2 but may readily be envisaged.

[0085] Contact member 12 engages a pair of first, resiliently deformable members 13a, 13b. Each of these is a cone of resiliently deformable material. The points 13c, 13d of the cones are positioned as shown in juxtaposition to one another and pointing towards the interior of the apparatus 10a, with the two resiliently deformable members 13a, 13b being essentially coplanar.

[0086] Each member 13a, 13b is supported at its widest end, opposite the aforesaid points, by a respective bracket 17a, 17b securing it to a rigid (e.g. metal, or another rigid material) upright 16a, 16b. The uprights 16a, 16b define left- and right-hand ends of a first layer of vibration-attenuating parts and are interconnected underneath the resiliently deformable members 13a, 13b by a rigid bar or plate 22 that in normal use extends horizontally.

[0087] The uprights 16a, 16b and the bar / plate 22 consequently define a U-shaped structure between the limbs of which the resiliently deformable members extend towards one another in a coplanar manner, such that the points of the conical members 13a, 13b lie spaced a short distance apart from one another at the same level in interior of the apparatus 10a. As a result of this arrangement a downwardly depending connection rod 23 that terminates in a horizontally extending plate 24 is able simultaneously to contact both the resiliently deformable members 13a, 13b, adjacent their respective tips 13c, 13d.

[0088] Each upright 16a, 16b is perforated or formed with a concave recess approximately half-way along its vertical length. The point of a respective conical, second resiliently deformable member 26, 27 is received in the resulting aperture or recess in each upright 16a, 16b in a manner ensuring contact between each upright 16a, 16b and a respective said second resiliently deformable member 26, 27.

[0089] The conical members 26, 27 are coplanar and each extend horizontally such that the widest parts of the members 26, 27 are spaced from the uprights 16a, 16b. At these ends that are spaced from the uprights 16a, 16b each second resiliently deformable member 26, 27 is secured by way of a bracket 28, 29 to a further respective upright 31, 32.

[0090] The further uprights 31, 32 are interconnected by a further rigid bar or plate 33 defining a base member such that the second resiliently deformable members 26, 27, uprights 31, 32 and further bar / plate 33 define a second U-shaped structure that is similar to but wider than that defined by the elements 16a, 16b and 22 and that amounts to a second layer of vibration-attenuating parts in the apparatus 10a. The second U-shaped structure as shown essentially surrounds the first U-shaped structure.

[0091] The further bar / plate rests on or is secured to a lintel, beam, screed, board or similar feature 19a defining the lowermost part of the floor cross-section.

[0092] When longitudinal vibration occurs in the lamina supported by contact member 12 this transmits via the connection rod 23 and plate 24 to the first resiliently deformable members 13a, 13b. Here the vibrational energy by reason of the elastomeric nature of the material of the members 13a, 13b and the lateral spacing of the connections of the parts of the apparatus, which as explained in relation to Figure 1 prevents the energy from propagating vertically downwardly in one and the same vertical cell or unit, converts to transverse vibrational energy and is dissipated in a similar manner to the operation of resiliently deformable member 13 in Figure 1.

[0093] However there may be an excess of energy in the vibrations over and above that which the resiliently deformable members 13a, 13b are able to dissipate. Furthermore the first resiliently deformable members may be able predominantly to dissipate energy only in a relatively limited range of frequencies. In order to ensure attenuation of vibrational energy that is as complete as possible therefore the second vibrationattenuating layer constituted by elements 26, 27, 28, 29, 31, 32, 33 operates in a similar manner to the first such layer. The ability in this way to cause the vibrational energy to transmit through more of the material of the resiliently deformable members provides for a greater degree of attenuation in general; and moreover if desired it is possible to tune the parts of the apparatus, and in particular the resiliently deformable members 13a, 13b, 26 and 27, such that each of the described layers attenuates vibrational energy in a respectively different frequency band.

[0094] Each of the resiliently deformable members 13a, 13b, 26 and 27 visible in Figure 2 overlies a respective, optional limit stop 21a, 21b, 21c, 21d. Each of these is identical or similar to the limit stop 21 of Figure 1 and performs the same function of preventing excessive deformation of the resiliently deformable members.

[0095] Further variants on the Figure 2 apparatus could include dispensing with the further rigid bar 33 and attaching the further uprights 31, 32 directly to e.g. a lintel 19a on which the apparatus 10a rests in use.

[0096] In use the apparatus 10a as illustrated would rest on, and indeed be pressed into contact with, the lintel 19. The apparatus may if desired be secured to the lintel etc. 19a, by any of a variety of means.

[0097] Another optional variant is to orientate the second resiliently deformable members 26, 27 and their associated supporting components to extend e.g. at right angles to the direction in which the first resiliently deformable members 13a, 13b extend. This may lead to additional compactness of the apparatus 10a and may assist to minimise the transmission of vibrational energy through the apparatus 10a.

[0098] The resiliently deformable members 13a, 13b, 26 and 27 do not have to be of the same design as is illustrated. Moreover they can be formed of either identical or differing materials, or differing grades or densities of the same material.

[0099] As in the case of the Figure 1 embodiment a plurality of the apparatuses 10a is likely in use to be provided, supporting a floor lamina at spaced intervals.

[0100] Figure 3 illustrates in side elevational view a variant 10b on the Figure 2 apparatus 10a. The apparatus 10b is similar to the apparatus 10a in that it includes two layers of vibration-attenuating parts. Apparatus 10b differs from apparatus 10a however in that, firstly, the resiliently deformable members 13a, 13b, 26 and 27 are formed as cylinders or cuboidal blocks of resiliently deformable material.

[0101] Furthermore an additional resiliently deformable member 34 is positioned between the free ends of the members 13a, 13b such as to be contacted by the connection rod 23 in preference to the free ends of the members 13a, 13b as in Figure 2. The additional resiliently deformable member is secured at each end by way of connectors 36, 37 to the free ends of the first resiliently deformable members 13a, 13b. The connectors 36, 37 are such as to transmit to the members 13a, 13b any vibrational energy that is not attenuated in the additional member 34 when the lamina supported on the contact member 12 is subjected to vibration.

[0102] This arrangement allows the plate 24 to be dispensed with since it is necessary to contact only a single member (i.e. additional member 34) with the connection rod 23. Figure 3 shows by way of schematic shading V the deflection of the additional resiliently deformable member that can arise when the contact member 12 experiences vibration. A further variant that is visible in Figure 3 is a common support 38 for the limit stops 21a, 21b. The common support is a rigid member such as a bar or plate that spans between the uprights 16a and 16b.

[0103] The limit stops 21a, 21b in Figure 2 are positioned to underlie, and limit the movement of, the additional resiliently deformable member 34. However these, or additional limit stops, could be provided in positions limiting the movement of e.g. the resiliently deformable members 13a, 13b.

[0104] Further, optional limit stops 39, 41 respectively extend from the uprights 31, 32 in order to underlie, and limit the movement of, the second resiliently deformable members 26, 27.

[0105] Combinations of the features of Figure 3 with those of e.g. Figure 2 are possible. Consequently it is possible for instance to mix different shapes of the resiliently deformable members, and / or different designs of the limit stops, in one and the same embodiment.

[0106] Plural examples of the apparatus 10b, or combinations of the different apparatus types described herein, may be used to support and attenuate vibration in one and the same lamina. Such plural apparatuses may be spaced e.g. at regular intervals or in a pattern as desired in order to provide particular attenuation effects.

[0107] As noted the parameters of the parts of the apparatus 10b may be selected so that each of the two vibration-attenuating layers may act chiefly to attenuate oscillations in a respective frequency band. Moreover the use of multiple resiliently deformable members increases, compared with Figures 1 and 2, the amount of elastomeric (or other resiliently deformable) material through which the vibrational energy passes in the form of transverse waves in order to undergo attenuation.

[0108] Figure 4 shows in schematic form a further embodiment of apparatus 10c, in which three layers of vibration-attenuating components are provided. In Figure 4 a contact member 12, which is a planar member that supports a lamina from underneath, rests or is secured on the free upper points of a pair of conical, first resiliently deformable members 13a, 13b.

[0109] The first resiliently deformable members 13a, 13b are secured at their lower, widened ends e.g. by rigid brackets 17a, 17b to a respective pair of support arms 16c, 16d. The support arms 16c, 16d extend inclinedly downwardly below the first resiliently deformable members 13a, 13b and meet at a lowermost point 16e.

[0110] Adjacent the lowermost point 16e each of the support arms 16c, 16d rests on and engages the point of a respective left and right, conical second resiliently deformable member 26, 27.

[0111] The members 26, 27 are secured to downwardly extending rigid uprights 31a, 32a e.g. through the use of bolts as illustrated, or other fastening means. The uprights 31a, 32a are similar to, and perform the same function as, the uprights 31, 32 of Figure 2. Consequently they are interconnected at their lower ends by a further rigid bar or plate 33 that also is similar in form and function to the counterpart element 33 of Figure 2.

[0112] The uprights 31a, 32a however differ from uprights 31, 32 in that they extend downwardly as illustrated below the further rigid bar 33. This is so the uprights 31a, 32a can respectively be engaged by the points of a pair of third, conical, resiliently deformable members 42, 43 that are secured on the left and right sides of the apparatus 10c by rigid brackets 44, 46 to additional, respective uprights 47, 48. The downward extensions of the uprights 31a, 32a may include recesses or apertures for the purpose of receiving the points of the conical members 42, 43. The additional uprights 47, 48 may be interconnected by an additional rigid bar 49 intended in use of the apparatus to act as a base member and rest on or be secured to an element such as a lintel or screed defining the lowermost extent of a void beneath a floor lamina.

[0113] It will be apparent that the respective pairs 13a, 13b; 26, 27; and 42, 43 of resiliently deformable members define three layers (identified, approximately, by the numerals ®, ® and ® in Figure 4) of vibration-attenuating components. Each of these layers operates in a similar manner to those described above, in that longitudinal vibration is converted by the contact of the various elements to transverse wave form, in which form it causes vibration of the molecules of the resiliently deformable members. This in turn causes dissipation of the vibrational energy through conversion chiefly to heat.

[0114] Figure 5 illustrates in schematic elevational view a further three-layer embodiment of apparatus lOd in accordance with the invention, with comparable elements to the previously described embodiments being referenced by the same numerals or, where appropriate, derivatives thereof.

[0115] The apparatus lOd is similar to the apparatus 10c of Figure 4, except firstly that the orientations of the first resiliently deformable members 17a, 17b (forming part of a first layer ® of vibration-attenuating components) differ from those in Figure 4 in the sense that the longitudinal axes of the members 13a, 13b extend horizontally instead of inclinedly. This permits a connection rod 23 that is similar to rod 23 of Figure 2 to engage the points of the conical, resiliently deformable members. Rod 23 in Figure 5 may include recesses or apertures on opposite sides so that the points of the resiliently deformable members may be received in them in a vibration-transmitting manner that also assures the integrity of the apparatus.

[0116] A rigid bar or plate 22 is desirable to connect and rigidify the uprights 31a, 32a that otherwise are equivalent to the uprights 31a, 32a of Figure 4.

[0117] The construction of the second layer ® of vibration-attenuating components in Figure 5, made up principally of the resiliently deformable members 26, 27, associated uprights 31a, 32a supporting the resiliently deformable members 26, 27 and further rigid bar 33 is essentially similar to the counterpart layer ® of Figure 4.

[0118] The third layer ® of vibration-attenuating components is similar to the layer ® of Figure 4, except that the directions of the third resiliently deformable members 42, 43 are reversed compared with Figure 4, such that the points of the conical members are "outboard" of the widest parts thereof. The shapes and sizes of the supporting rigid elements adjusted accordingly in order to provide adequate support for the thus- orientated members 42, 43.

[0119] The various uprights 16c, 16d, 47 and 48 may include apertures or recesses for the purpose of receiving the tips of the respective conical, resiliently deformable members. Brackets, that may be of similar designs to those previously described or may differ therefrom, are provided to secure the wide ends of the resiliently deformable members.

[0120] The Figure 5 apparatus lOd operates in a similar manner to the Figure 4 apparatus 10c. Figure 5 shows overlain on the image shading and arrows that represent the presently believed understanding of propagation of vibrational energy around the apparatus lOd. Multiple passes of the energy around the transmission loops represented respectively by the first, second and third layers of vibration-attenuating components gives rise to a high degree of energy dissipation, with the result that the apparatus is highly effective at providing vibration isolation. Reflection of vibrational energy may in some instances occur, and this in part gives rise to transmission of energy around the parts of the apparatus in a loop-like manner as schematically shown.

[0121] It should be noted that the shading in Figure 5 may be a simplification of the actual paths taken by vibrational energy in the apparatus lOd, and this figure is intended to be indicative of general principles of transmission. A more complex transmission pattern than that shown, involving e.g. harmonic frequencies and mixes of wave form types, is likely to arise in practical situations. This indeed is one reason why a multilayer apparatus is believed likely to be more effective at attenuating vibrations than a single-layer device such as apparatus 10. In the latter the single energy-absorbing layer may not be efficient at attenuating all the harmonics and wave form types that may arise.

[0122] In other words vibrational loop effects of the general kind illustrated in Figure 5 may arise, and be effectively attenuated, in many if not all of the embodiments described herein and derivatives thereof as will occur to the person of skill in the art.

[0123] Figure 6 shows a two-layer variant lOe, of the three-layer construction of Figure 4. Apparatus lOe comprises the components 13a, 13b, 16c, 16d, 26, 27, 31a, 32a and 33 of Figure 4 that constitute the layers ® and ® of that Figure. The Figure 6 apparatus lOe omits the components making up the third layer ® of Figure 4. The uprights 31a, 32a in Figure 6 are of a modified shape compared with Figure 4 in order to accommodate and support the chosen sizes of the resiliently deformable members 26, 27. However in other embodiments, depending on the exact design of the parts, such modification may not be needed.

[0124] Based on the foregoing descriptions the operational principles of the apparatus lOe may readily be envisaged, with longitudinal vibrations in the lamina 11 being converted to transverse wave form by conduction through the parts of the apparatus lOe such that the vibrational energy passes along the resiliently deformable members in a manner leading to vibration attenuation.

[0125] As in the case of all the other variants of the apparatus, the Figure 6 apparatus lOe may be deployed on its own or as one of a plurality of apparatuses. When plural apparatuses are used they may all be of the same design, or they may be of differing designs, sizes and materials. Within one and the same apparatus lOe the resiliently deformable members 13a, 13b, 26 and 27 may be all of the same design and / or material or they may differ from one another in various respects such as dimensions, material specifications, densities and so on in order to produce desired vibration attenuation effects.

[0126] Figure 6 additionally shows, in a manner that is exaggerated for purposes of illustration, that the apparatus may readily be employed when the lamina 11 is not parallel to the lowermost floor layer 33. Such a situation may arise for example if the lamina is installed in a sloping manner as indicated; or more commonly because the lowermost layer 33 includes one or more uneven areas, changes in height and / or slopes. Also in some installations the lamina 11 may be capable of tilting, and the inclination of it in Figure 6 schematically represents this possibility as well. The apparatus 10 is believed to be superior to prior art arrangements in accommodating such aspects of floors as are embraced by the tilting of lamina Il in Figure 6.

[0127] Although only Figure 6 shows inclination of floor parts as illustrated, all the embodiments described herein similarly may be employed in ways that accommodate such features of a floor construction.

[0128] Figure 7 illustrates in schematic, elevational view a further variant of apparatus lOf that in essence is a combination of layers ® and ® visible in Figure 5. These layers adopt a similar form to their counterparts in apparatus lOd, except that a common upright 50 is provided at the lowermost layer ® in order jointly to support the resiliently deformable members 42, 43. The common upright 50 may be connected to a stand 51 that in the illustrated embodiment adopts a box-like structure made up of rigid elements such as metal sheets as illustrated. The stand 51 may be positioned to rest or be secured on a further component such as a lintel, screed or similar element 19a defining the lowermost part of a floor void.

[0129] Operation of the Figure 7 apparatus lOf may readily be envisaged based on the foregoing descriptions, which apply mutatis mutandis to the apparatus lOf. Variations and combinations of the apparatus lOf may be the same as or similar to those described above.

[0130] Figures 8 and 9 respectively are a side elevational and front elevational view of a further embodiment 10g of apparatus, according to the invention, that includes a pivot joint between the contact member 12 and one or more resiliently deformable member of the apparatus. The purpose of the pivot joint, as explained below, is to stabilise the apparatus by limiting the number of degrees of freedom of movement of the parts, while permitting sufficient movement to promote attenuation of vibration transmitted through the apparatus.

[0131] In Figure 8 a contact member in the form of a plate 12 that may be of a similar design to those of the apparatuses 10, 10a, 10b, 10c, lOd, lOe and lOf described above underlies, and supports from beneath, a lamina such as a floor. Contact member 12 is connected by way of a downwardly extending, rigid connection rod or plate 23 to the point of a conical first resiliently deformable member 13. The point 13c of the resiliently deformable member is received in an aperture or recess 52 formed in the connection rod / plate 23, such that the point 13c is loosely captive therein.

[0132] The first resiliently deformable member 13 expands in diameter in the direction away from the point 13c. At its widest part the resiliently deformable member 13 is secured to a threaded rod 53 that is coaxial with the longitudinal axis of the cone shape of the resiliently deformable member 13.

[0133] The end of threaded rod 53 extending away from the resiliently deformable member 13 is threadedly received in a composite mounting block 54 that is supported from above by a further connection rod 56. This is secured to the mounting block 54 at its lower end and the underside of the contact member 12 at its upper end, at a location spaced along the contact member 12 from the connection rod 23. Mounting block 54 is itself pivotably mounted by way of left and right resiliently deformable, or at least flexible, pivot cones 57, 58 supported each at the same height relative to the mounting block 54 on respective left and right cone uprights 59, 61 that are themselves secured by way of connected flanges 62, 63 to e.g. a lintel 19.

[0134] The points of the pivot cones 57, 58 are received in recesses formed in the left and right sides of the mounting block, such that the mounting block may rotate relative to the remainder of the apparatus 10g. Such rotation is signified by the double-headed arrow in Figure 8.

[0135] The composite mounting block 54 as shown adopts a sandwich construction in which an elongate centre layer 54a is of a different material than upper and lower, laminar outer layers 54b, 54c. The centre layer 54a may be formed of a material that provides e.g. resilient support for the points of the member 57, 58. The outer layers 54b, 54c may be formed from rigid materials such as metals in order to provide firm anchoring points for any attached components, and ensure correct supporting of the centre layer 54a.

[0136] The described sandwich construction however is optional and it may be possible to form the mounting block 54 from a single material.

[0137] The arrangement of apparatus 10g is such that on the contact member 12 being subjected to longitudinal vibration this transmits via the connection rod or plate 23 to the point 13c of the first resiliently deformable member 13. The vibrational energy at this point converts to transverse wave form and transmits along and through the material of the resiliently deformable member 13. As in the other apparatuses described herein this causes attenuation of the vibrational energy, primarily through conversion to heat.

[0138] During such attenuation the contact member 12, connection rod or plate 23 and further connection rod 56 are free to rotate by reason of the pivotal connection created by receipt of the points of the pivot cones 57, 58 in the side recesses of the mounting block.

[0139] Pivoting mounting as described herein is an optional feature in most if not all embodiments of the invention. Since the resiliently deformable member 13 is mounted by way of the screw thread of the threaded rod 53 it is possible to adjust the extent to which the resiliently deformable member 13 protrudes from the mounting block 54. As a result it is possible to tune the resonant frequency of the apparatus 10g and / or to apply a pre-load to the engagement of the resiliently deformable member 13 with the connection rod or plate 23. Such adjustability allows tuning of the properties of the apparatus 10g.

[0140] Additionally or alternatively it is possible to apply a pre-load during manufacturing of the apparatus, for example through use of a G-clamp or functionally similar means to compress the layers of the apparatus before using one or more fastening means to secure the layers in contact one with another. The precise method of using a G-clamp for this purpose will readily occur to the person of skill in the art. Moreover applying a pre-load in this way is possible, as desired, in respect of most if not all embodiments of the invention.

[0141] Figure 10 illustrates in schematic, side elevational view another apparatus lOh, according to the invention, that is similar to the Figures 8 and 9 apparatus 10g.

[0142] In Figure 10 the contact member 12 underlies and engages from underneath a lamina that may be subject to longitudinal vibration. A connection rod or plate 23 extends downwardly from the underside of contact member 12 and includes an aperture or recess 52 in which is received the point of a conical, resiliently deformable member 13.

[0143] Resiliently deformable member 13 is mounted in a similar way to the counterpart member 13 in Figure 8 on a threaded rod 53 that is threadedly received in a bore formed in a rigid upright 64 extending upwardly from the upper surface of a base member 19.

[0144] A further, similar upright 66 also extends from the upper surface of base member 19 a short distance from upright 64. The space between the upper ends of the uprights 64, 66 is spanned by a resiliently deformable bar 67 that is secured by respective fixings such as but not limited to the screws 68, 69 visible in Figure 10. Bar 67 may be made from a natural or synthetic elastomer such as a rubber or similar compound.

[0145] The upper surface of bar 67 includes formed therein a recess 71 extending part-way through its thickness. The lower end 72 of a rigid pivot bar 73 is received in the recess 71. Recess 71 is formed as a part-spherical or part-circular shape and end 72 is of complementary shape such that end 72 is rotatable in the recess 71. Pivot bar 73 extends upwardly to be secured to the underside of contact member 12 at a location above the recess 71.

[0146] The apparatus lOh of Figure 10 operates in a similar manner to apparatus 10g of Figures 8 and 9, in that longitudinal vibrational energy experienced at the contact member 12 is transmitted via the connection rod or plate 23 to the point of resiliently deformable member 13. At this point the energy converts to transverse wave form and transmits through and along the member 13, with dissipation as in the other resiliently deformable members described herein.

[0147] Any transverse wave form vibrational energy not dissipated in the resiliently deformable member 13 may be dissipated in the material of the resiliently deformable bar.

[0148] Motion of the contact member 12 relative to the remainder of the apparatus lOh is accommodated by the pivoting mounting of the contact member 12 via pivot bar 73, pivot bar end 72 and recess 71. The force applied by the resiliently deformable member 13 at the recess / aperture 52 is adjustable through rotation of the threaded rod 53. Such motion is schematically represented by the double-headed arrow in Figure 10.

[0149] Figure 11 shows in perspective view a practical version lOi of the apparatus of the invention, in which the components of for example the Figure 2 embodiment are shown.

[0150] In Figure 11 the contact member 12 is formed from a metal, e.g. steel, plate or sheet that has undergone sheet metal fabrication steps to create the box-like structure shown. Contact member 12 includes as an optional feature 12a an aperture that may be used to receive and / or mount a fastener that secures the supported lamina, which rests on the contact member 12, in a manner preventing or reducing relative movement between the lamina and the apparatus lOi.

[0151] Contact member 12 is rectangular and by reason of the aforesaid box-like construction includes extending along each of two opposite edges of the rectangular shape a respective downwardly depending, rigid skirt 12', 12". The skirts 12', 12" are angled inwardly and each include a pair of longitudinally spaced mounting apertures via which a respective resiliently deformable member 13a, 13b, 13c, 13d is mounted. The angling of the respective skirts means the resiliently deformable members protrude in a downwardly inclined manner as shown.

[0152] Each of the resiliently deformable members consists of s solid cylinder of a resiliently deformable material, such as a natural or synthetic rubber, that is secured at one end in one of the mounting apertures and the opposite end of which is essentially untethered. Each member 13 tapers to a point at its untethered end. The contact member, skirts and resiliently deformable members 13 define a first vibrationattenuating layer of the apparatus.

[0153] The untethered ends of the resiliently deformable members 13a, 13b, 13c, 13d are received in respective, appropriately aligned apertures 16', 16", 16'", 16"" formed at spaced intervals along a respective rigid (e.g. metal) upright 16 partly defining a second vibration attenuating layer of the apparatus lOi.

[0154] The second vibration attenuating layer is constituted primarily by an open, box-like structure including left- and right-hand, rigid uprights 31, 32 defining two sides of an open-topped square the interconnecting sides of which are defined by the uprights 16.

[0155] The uprights 31, 32 are inclined relative to the vertical and each have secured so as to protrude on their outer edges a respective pair of further resiliently deformable members 26, 26', 27, 27'. The resiliently deformable members 26, 26', 27, 27' are of the same design as the members 13. Their longitudinal axes extend in directions that are rotated 90° relative to the general axial dimensions of the members 13.

[0156] The protruding free ends of the members 26, 26', 27, 27' are received in apertures or recesses 91', 91", 92', 92" formed in further uprights 91, 92 that are interconnected at the bottom of the apparatus lOi by a rigid plate 33 defining a base member.

[0157] In the illustrated embodiment the various resiliently deformable members are secured to their associated rigid members by way of threaded studs protruding from their in- use rear ends. The studs pass through apertures in the rigid members and receive nuts 93 or similar fastenings in order rigidly to secure the resiliently deformable members in position.

[0158] The illustrated resiliently deformable members are made as two-part constructions, within each case a cylindrical body of resiliently deformable material having secured on its end remote from the attached stud a tapered section of resiliently deformable material.

[0159] This construction is not mandatory but it does confer an advantage of being able to design the properties of the resiliently deformable members in a manner that is tailored to the expected use requirement of the apparatus.

[0160] The apparatus lOi functions essentially in the same way as the Figure 2 apparatus, with longitudinal vibrations received at the contact member 12 being converted in the resiliently deformable members to transverse wave form, with energy dissipation in the form of heat generation, in two stages corresponding to transfer of the energy via the two attenuating layers described above. The mutually orthogonal orientation of the resiliently deformable members of the respective layers, together with the presence of two such layers, assists to ensure attenuation that is as complete as possible. However this aspect is optional and may be varied in alternative versions of the apparatus lOi. Similarly for example the inclined nature of the uprights 31, 32 is optional and may be varied or dispensed with in other embodiments.

[0161] The rigid parts of the apparatus lOi are shown as made from a rigid metal such as mild steel. They could however be made from a range of other materials. Mixtures of constructional materials in one and the same embodiment are possible and readily may be envisaged by the person of skill in the art.

[0162] Figure 12 illustrates in side elevational view a further apparatus lOj that embodies the principles of the invention.

[0163] In Figure 12 a contact member 12 is formed from an essentially rigid material such as a metal, wood or a plastic. Plastic materials may be attractive because they can be made (for example by extrusion, additive manufacturing, moulding or so-called "3D printing" techniques) in almost any length. Contact member 12 is intended to engage from underneath, and hence support, a lamina such as a floor element.

[0164] A first connection member 23 is secured to and extends downwardly from the underside of contact member 12 and rests on the upper surface of a strip 13 of resiliently deformable material.

[0165] A rigid base member 19 extends below the resiliently deformable strip 13 and is spaced therefrom by a series of vertically extending lower connection members 77 that are fixed to the base member. The lower connection members 77 interconnect the base member and the resiliently deformable strip 13.

[0166] In practice more than one of the first connection members 23 would be provided extending between the contact member and the resiliently deformable strip 13 in order to ensure stability of the structure.

[0167] One or more of the connection members 23, 77 may taper e.g. in a longitudinal direction that is perpendicular to the plane of Figure 12 and / or in a vertical direction. Such optional tapering is illustrated in Figure 12 by the vertical lines shown. In Figure 12 all the connection members 23, 77 are indicated as tapering in the same direction, but this need not be the case. On the contrary, alternating or other (including irregular) patterns of taper directions made be constructed.

[0168] In use of the apparatus lOj any longitudinal vibration transmitted from a floor lamina to the contact member 12 transmits via the first connection member 23 to the layer (strip) 13 of resiliently deformable material. Here the vibrational energy converts to transverse wave form and passes along and through the material of the strip / layer 13, in the process undergoing attenuation.

[0169] The lower connection members 77 and the base member 19 provide support for the apparatus.

[0170] In practice the apparatus lOj is likely to be manufactured as an elongate strip that may be cut to appropriate lengths when it is required to use it to support a floor lamina. Plural such lengths can be employed to provide spaced, vibration attenuating support for a floor lamina.

[0171] The apparatus lOj may be provided in a preassembled state, in which the illustrated layers are secured one to another; or as a kit in which the layers are provided separately. At least in the latter case the layers may be provided in the form of a roll from which they can be dispensed in use. The layers 12 and 19 when provided in this form may include the connection members 23 and 77 secured thereto; or these may be provided secured to the layer 13. Yet a further possibility is for one class of the connection members 23, 77 to be connected to the resiliently deformable layer 13 and the other to one of the layers 12, 19. Clearly the choice of material of (in particular) the contact member 12 is important in providing sufficient rigidity to enable the apparatus to function while also permitting rolling and unrolling of the layers. When provided in kit form the layers may on installation optionally be secured one to another using e.g. an adhesive material, friction fasteners included in the construction of the layers, or any other appropriate fastening means as would occur to the person of skill in the art.

[0172] Although the use of fastening means to secure the layers together is preferred it is possible to dispense with fastening means and rely instead on downward pressure from the floor lamina to maintain the layers in contact with one another in a mutually aligned manner.

[0173] The layers of the apparatus lOj when it is pre-assembled also in some circumstances be provided e.g. in the form of a roll of material.

[0174] The materials of the parts of apparatus lOj typically may be capable of being cut, if necessary using cutting apparatus, in order to provide the desired lengths of the apparatus.

[0175] A refinement 10k of the apparatus of Figure 12 is shown in side elevational view in Figure 13. In this apparatus 10k two layers are provided, one on top of the other, each adopting essentially the construction of apparatus lOj.

[0176] Hence in Figure 13 an elongate (e.g. strip-like or roll form) contact member 12 is intended to engage from below, and support, a floor lamina. Contact member 12 is sufficiently rigid as to conduct longitudinal vibration via a series of connection members 23 depending at spaced intervals along the contact member from its underside to engage the upper surfaces of a series of longitudinally spaced first resiliently deformable members 13. These members 13 adopt the form of a series of cuboidal blocks of elastomeric material.

[0177] An intermediate member 78, that also is of strip-like form, lies beneath the row of first resiliently deformable members 13 and is connected thereto by a series of upwardly extending further connection members 79 that protrude upwardly from its upper surface and respectively engage the lower surfaces of first resiliently deformable members 13.

[0178] A series of additional connection members 81 extends at intervals along the length of the underside of intermediate member 78 and engage the upper surfaces of a second series of resiliently deformable members 82. Members 82 may be similar to members 13 and hence may be formed of an elastomeric material the same as that of member 13, or that may differ therefrom in line with the principles described herein.

[0179] A base member 19 that also is of strip-like form extends underneath the second row of resiliently deformable members 82 and includes extending upwardly at intervals along its length a series of base connection members 83 that interconnect the respective second resiliently deformable members 82 and the base member 19. Base member 19 and the base connection members are in like manner to the members 13 and 78 made of relatively rigid materials.

[0180] The layers of the apparatus 10k are arranged in use parallel to one another as illustrated. The base member 19 may rest on or be secured to e.g. a lintel, screed, beam or similar rigid element defining the lowermost part of the cross-section of a floor.

[0181] Operation of the apparatus 10k involves longitudinal vibrations being received at the contact member 13 and transmitted via the connection members 23 to the first resiliently deformable members 13. Here the vibrational energy converts to transverse form and attenuation takes place.

[0182] Any excess vibrational energy, or energy of a non-absorbed frequency, then transmits via intermediate member 78 to the second resiliently deformable members 82 where further attenuation occurs. Consequently, little or no vibrational energy reaches the base member 19; and vibrational isolation of the supported floor lamina is achieved.

[0183] The double-headed arrow visible in Figure 13 schematically shows that a loop-like path of vibrational energy, that is similar to that shown in Figure 5, may arise in apparatuses such as those of Figures 12 and 13.

[0184] Possible variants on the embodiment shown in Figure 13 include widening the resiliently deformable members 13 and / or the resiliently deformable members 82 such that they span (as appropriate) two or more of the connection members 79 or 81. It further is possible to manufacture the resiliently deformable layers 13 and / or 82 as continuous strips of resiliently deformable material that each span multiple connection members; but it is believed that such an embodiment while effective to attenuate transmitted vibration does not do so as efficiently as the longitudinally discontinuous members illustrated. In Figure 13 the resiliently deformable members 13 are of the same size and are positioned essentially in register with the members 82, but neither of these parameters necessarily needs to be observed. Hence the numbers and sizes of the resiliently deformable members in the respective rows may differ, and indeed it is possible for one of the rows to include only a single resiliently deformable member 13 or 82. In such a case the number of connection members may if desired be reduced to match the number of resiliently deformable members in each row.

[0185] As indicated it is not essential for the members of the rows of resiliently deformable members to be in register with one another; and indeed this may be impossible if the resiliently deformable members in the respective rows are not all of the same dimensions. Furthermore the resiliently deformable members 13, 82 in a single row may differ from one another as to dimensions, spacings, density and material choice.

[0186] The layers visible in Figures 12 and 13 may be manufactured in any chosen width that is suitable for supporting a floor lamina. In some embodiments the layers may be 2 - 5 cm wide, but this is not to be construed as limiting.

[0187] Methods of operation of the various apparatuses are as described herein and are within the scope of this disclosure. Furthermore the invention extends to a lamina, such as but not limited to a laminar element of a floor, when it is supported in a vibrationattenuating manner on any of the apparatuses described herein or clear derivatives thereof.

[0188] Overall the invention provides an efficient way of installing vibration-absorbing material as part of a floor construction, using apparatuses that are effective to attenuate vibrational energy and yet which do not require power supplies. A plurality of apparatuses according to the invention readily may isolate from vibration transmission large areas of flooring, in a manner that requires little or no expertise to install.

[0189] The listing or discussion of an apparently prior-published document in this specification should not necessarily be taken as an acknowledgement that the document is part of the state of the art or is common general knowledge.

[0190] Preferences and options for a given aspect, feature or parameter of the disclosure should, unless the context indicates otherwise, be regarded as having been disclosed in combination with any and all preferences and options for all other aspects, features and parameters of the disclosure.

Claims

CLAIMS1. A vibration attenuation apparatus, for supporting a lamina, comprising a contact member for contacting from underneath, and thereby supporting, a lamina; at least one, first resiliently deformable member; and a further member for supporting the first resiliently deformable member, the contact member and the further member engaging the first resiliently deformable member at mutually laterally spaced locations whereby longitudinal wave vibrational energy received at the contact member from a supported lamina is transmitted through and along a length of the first resiliently deformable member towards the further member such that the first resiliently deformable member causes attenuation of the vibrational energy.

2. Apparatus according to Claim 1 including a plurality of the first resiliently deformable members, the contact member and the further member contacting each said first resiliently deformable member at mutually laterally spaced locations whereby longitudinal wave vibrational energy received at the contact member from a supported lamina is transmitted through and along a length of each first resiliently deformable member towards the further member with conversion to transverse wave form such that the first resiliently deformable members cause attenuation of the vibrational energy.

3. Apparatus according to Claim 1 or Claim 2 wherein the or each first resiliently deformable member lies or extends below the contact member, wherein the contact member includes a planar upper surface for supporting a lamina and wherein the apparatus further includes at least one downwardly extending protrusion connecting the contact member and one or more of the first resiliently deformable members each at a first lateral location on the respective first resiliently deformable member.

4. Apparatus according to Claim 3 wherein the further member lies below the or each first resiliently deformable member and wherein the apparatus includes at least one upwardly extending protrusion connecting the further member and one or more of the first resiliently deformable members each at a second lateral location on the respective first resiliently deformable member that is laterally spaced along the first resiliently deformable member from the first lateral location.

5. Apparatus according to any preceding claim further including at least one second resiliently deformable member and a base member, the further member and the base member contacting the second resiliently deformable member at mutuallylaterally spaced locations whereby longitudinal wave vibrational energy received at the further member is transmitted through and along a length of the second resiliently deformable member towards the base member with conversion to transverse wave form such that the second resiliently deformable member causes further attenuation of the vibrational energy.

6. Apparatus according to Claim 5 including a plurality of the second resiliently deformable members, the further member and the base member contacting each said second resiliently deformable member at mutually laterally spaced locations whereby longitudinal wave vibrational energy received at the further member is transmitted through and along a length of each second resiliently deformable member towards the base member with conversion to transverse wave form such that the second resiliently deformable members cause further attenuation of the vibrational energy.

7. Apparatus according to Claim 6 wherein the or each second resiliently deformable member lies or extends below the further member, wherein the wherein the apparatus further includes at least one downwardly extending protrusion connecting the further member and one or more of the second resiliently deformable members each at a first lateral location on the respective second resiliently deformable member and wherein the apparatus further includes at least one upwardly extending protrusion connecting the base member and one or more of the second resiliently deformable members each at a second lateral location on the respective second resiliently deformable member that is laterally spaced from the first lateral location.

8. Apparatus according to any preceding claim including a pivot joint interconnecting (a) the contact member, or (b) an additional member engaging the contact member, and the resiliently deformable member whereby to constrain the number of degrees of freedom of the contact member and the resiliently deformable member one relative to the other.

9. Apparatus according to any preceding claim including one or more limit stop that is secured relative to the further member and acts during operation of the apparatus to limit movement of the contact member and the resiliently deformable member one relative to the other.

10. Apparatus according to Claim 5 or any preceding claim depending therefrom wherein the contact member, the one or more first resiliently deformable member, the one or more second resiliently deformable member, the further member and the basemember are arranged to define an oscillation loop around which longitudinal vibrational energy may propagate with transmission along at least part of at least one said first resiliently deformable member and along at least part of at least one said second resiliently deformable member, with attenuation of vibrational energy and at least one transformation between longitudinal and transverse vibrational wave forms.

11. Apparatus according to any preceding claim including one or more mounting for one or more said first or second resiliently deformable member the length of which is adjustable so as to permit adjustment of the position of the respective resiliently deformable member relative to the remainder of the apparatus.

12. Apparatus according to Claim 1 wherein the at least one resiliently deformable member is or includes a layer of resiliently deformable material; wherein the contact member is a laminar member and the apparatus includes protruding downwardly between the laminar member and the layer of resiliently deformable material a series of contact member protrusions that contact an upper surface of the layer at a series of mutually laterally spaced upper surface locations; and wherein the further member is a laminar member and the apparatus includes protruding upwardly therefrom a series of further member protrusions that contact a lower surface of the layer of resiliently deformable material at a series of mutually laterally spaced lower surface locations, the mutually laterally lower surface locations also each being spaced laterally from the mutually laterally spaced upper surface locations.

13. Apparatus according to Claim 12 wherein each contact member protrusion is elongate, extends transversely from one side of the contact member to the other, tapers in a protrusion width direction along its length and protrudes downwardly to a varying extent along its length.

14. Apparatus according to Claim 12 or Claim 13 wherein each further member protrusion is elongate, extends transversely from one side of the further member to the other, tapers in a protrusion width direction along its length and protrudes upwardly to a varying extent along its length.

15. A method of attenuating longitudinal wave vibration in a lamina, the method comprising causing longitudinal vibrational energy in the lamina to transmit to a contact member supporting the lamina from underneath, and thence to a first location in at least one resiliently deformable member; causing a further member to engage and support the resiliently deformable member at a second location that is laterallyspaced from the first location; and causing the vibrational energy to transmit with attenuation along a length of the resiliently deformable member towards the further member.

16. A method according to Claim 15 wherein the step of causing the vibrational energy to transmit with attenuation along a length of the resiliently deformable member includes conversion of vibrational energy to transverse wave form.

17. A method according to Claim 15 or Claim 16 including causing or permitting pivoting connection between the contact member and the at least one resiliently deformable member whereby to constrain the number of degrees of freedom of the contact member and the resiliently deformable member one relative to the other.

18. A method according to any of Claims 15 to 17 including causing a limit stop, that is fixed relative to the further member, to limit movement of the contact member and the resiliently deformable member one relative to the other.

19. A lamina supported by one or more apparatus according to any of Claims 1 to 14 and / or in which attenuation of vibrational energy occurs in accordance with the method of any of Claims 15 to 18.

20. A lamina according to Claim 19 when supported on a plurality of the apparatuses that are spaced apart from one another beneath the lamina.

21. A lamina according to Claim 20 wherein the apparatuses are spaced apart at least in the plane of the underside of the lamina in a regular pattern.

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