Installation elements and methods for fastening an installation element to a work surface

RELATED APPLICATION

0001This patent arises from a continuation of International Patent Application PCT/EP2003/08982, which was filed on 13 Aug. 2003 and which is incorporated herein by reference in its entirety.

FIELD OF THE DISCLOSURE

0002The present disclosure relates to installation elements, in particular sinks, for insertion into a receiving opening of a work surface, wherein the installation element has at least one holding element.

0003The present disclosure additionally relates to methods for fastening an installation element, in particular a sink, to the edge of a receiving opening for the installation element in a work surface, wherein the installation element has at least one holding element.

BACKGROUND

0004Installation elements and methods for fastening them to a work surface are known from the prior art.

0005Thus, an installation element is known from DE 44 37 630 C1, for example, which has a holding element configured as a holding web and can be fastened in a recess of a work surface by inserting the holding bar into holding clamps fastened to the edge of the recess and anchoring it by latching it in the holding clamps.

0006The disadvantage with this known method is that additional structural parts are required, namely the holding clamps to be fastened to the work surface, and that the edge of the receiving opening in the work surface must be cut with low tolerances, so that the holding element can be latched into the holding clamps.

BRIEF DESCRIPTION OF THE DRAWINGS

0007<figref idref="DRAWINGS">FIG. 1</figref> is a schematic plan view from above onto an example sink unit, which is received in a receiving opening of a work surface.

0008<figref idref="DRAWINGS">FIG. 2</figref> is a schematic plan view from below onto the sink unit received in the receiving opening of the work surface.

0009<figref idref="DRAWINGS">FIG. 3</figref> is a schematic sectional view through the sink unit and a holding element fastened to its underside as well as an edge region of the work surface directly after a variable-volume material has been applied.

0010<figref idref="DRAWINGS">FIG. 4</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 3</figref> after a first curing stage of the variable-volume material.

0011<figref idref="DRAWINGS">FIG. 5</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 3</figref> after a dry expansion of the variable-volume material.

0012<figref idref="DRAWINGS">FIG. 6</figref> is a schematic sectional view through an example sink unit with a holding element fastened to its underside, which has a torque stop, and an edge region of the work surface.

0013<figref idref="DRAWINGS">FIG. 7</figref> is a schematic sectional view through an example sink unit with a holding element fastened thereto and an edge region of a work surface, wherein the edge of the work surface is sealed with a variable-volume material, directly after the variable-volume material has been applied.

0014<figref idref="DRAWINGS">FIG. 8</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 7</figref> after a first curing stage of the variable-volume material.

0015<figref idref="DRAWINGS">FIG. 9</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 7</figref> after a dry expansion of the variable-volume material.

0016<figref idref="DRAWINGS">FIG. 10</figref> is a schematic sectional view through an example sink unit with a holding element fastened to its underside and an edge region of a work surface, which has a sloping edge, directly after the variable-volume material has been applied.

0017<figref idref="DRAWINGS">FIG. 11</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 10</figref> after a first curing stage of the variable-volume material.

0018<figref idref="DRAWINGS">FIG. 12</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 10</figref> after a dry expansion of the variable-volume material.

0019<figref idref="DRAWINGS">FIG. 13</figref> is a schematic sectional view through an example sink unit with a holding element fastened to its underside, which has a lower contact surface inclined towards the horizontal, and an edge region of a work surface.

0020<figref idref="DRAWINGS">FIG. 14</figref> is a schematic sectional view through an example sink unit with a holding element fastened to its underside and an edge region of a work surface, which is provided on its upper side with a support strip for a clamping body.

0021<figref idref="DRAWINGS">FIG. 15</figref> is an-enlarged representation of region I in <figref idref="DRAWINGS">FIG. 14</figref>.

0022<figref idref="DRAWINGS">FIG. 16</figref> is a schematic sectional view through an example sink unit with a holding element fastened to its underside, which has a blade guide, and an edge region of a work surface.

0023<figref idref="DRAWINGS">FIG. 17</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 16</figref>, during detachment of a clamping body from the work surface by means of a blade.

0024<figref idref="DRAWINGS">FIG. 18</figref> is a schematic sectional view through an example sink unit with a holding element fastened to its underside, on which a separating element is arranged to cut through a clamping body, and an edge region of a work surface.

0025<figref idref="DRAWINGS">FIG. 19</figref> is a schematic side view of an example sink unit arranged in a receiving opening of a work surface with operating handles to operate a separating element for cutting through a clamping body.

0026<figref idref="DRAWINGS">FIG. 20</figref> is a schematic plan view from below onto the sink unit received in the receiving opening of the work surface from <figref idref="DRAWINGS">FIG. 19</figref>.

0027<figref idref="DRAWINGS">FIG. 21</figref> is an enlarged representation of region II in <figref idref="DRAWINGS">FIG. 20</figref>.

0028<figref idref="DRAWINGS">FIG. 22</figref> is a schematic sectional view through an example sink unit with a holding element fastened to its underside, an edge region of a work surface, which has a sloped edge, and a variable-volume material enclosed by a flexible tube.

0029<figref idref="DRAWINGS">FIG. 23</figref> is a schematic longitudinal section through a variable-volume material enclosed by a flexible tube and a capsule containing a hardener material, which can be passed through the tube.

0030<figref idref="DRAWINGS">FIG. 24</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 22</figref> after an expansion of the variable-volume material.

0031<figref idref="DRAWINGS">FIG. 25</figref> is a schematic sectional view through an example sink unit with a holding element fastened to its underside, an expansion restricting body arranged on the holding element and an edge region of a work surface, directly after a variable-volume material has been applied.

0032<figref idref="DRAWINGS">FIG. 26</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 25</figref> after a first curing stage of the variable-volume material.

0033<figref idref="DRAWINGS">FIG. 27</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 25</figref> after a dry expansion of the variable-volume material.

0034<figref idref="DRAWINGS">FIG. 28</figref> is a schematic sectional view through an example sink unit with a holding element fastened to its underside, on which a separating element is arranged to cut through a clamping body, and an edge region of a work surface, directly after a variable-volume material has been applied.

0035<figref idref="DRAWINGS">FIG. 29</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 28</figref> after a first curing stage of the variable-volume material.

0036<figref idref="DRAWINGS">FIG. 30</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 28</figref> after a dry expansion of the variable-volume material.

0037<figref idref="DRAWINGS">FIG. 31</figref> is a schematic sectional view through an example sink unit with a holding element fastened to its underside, which has a lower contact surface inclined towards the horizontal, and an edge region of a work surface, wherein on the edge of the work surface a support strip prestressed by a spring is arranged to support a clamping body, directly after a variable-volume material has been applied.

0038<figref idref="DRAWINGS">FIG. 32</figref> is a sectional view corresponding to <figref idref="DRAWINGS">FIG. 31</figref> after a dry expansion of the variable-volume material.

0039Identical or functionally equivalent elements are provided with the same reference numerals in all figures.

DETAILED DESCRIPTION

0040An example sink unit shown in <figref idref="DRAWINGS">FIGS. 1 and 2</figref> and given the overall reference <b>100</b> comprises a main basin <b>102</b> with a drain <b>104</b> and a waste basin <b>106</b> with a drain <b>108</b>, which are arranged in a horizontal sink surface <b>110</b>, as well as a rear fitting support surface <b>112</b> with a through hole <b>114</b> to receive a mixer tap unit (not shown), a front fitting support surface <b>116</b> with a through hole <b>118</b> to receive a cam to operate a drain plug and a drip surface <b>120</b> connecting to the waste basin <b>106</b> on the left.

0041The sink unit <b>100</b> is provided with a circumferential sink edge <b>122</b> (see <figref idref="DRAWINGS">FIG. 3</figref>), which comprises a horizontal sink edge face <b>123</b>, which descends via an inner convexly curved region <b>124</b> and an inner slope <b>126</b> to the horizontal sink surface <b>110</b> and via an outer convexly curved region <b>128</b> and an outer slope <b>130</b> to an outer edge <b>132</b> of the sink unit <b>100</b>.

0042The curved regions <b>128</b> and <b>124</b> are convexly curved in plan view from above onto the sink unit <b>100</b>; these regions are therefore concavely curved in plan view from below onto the sink unit <b>100</b>.

0043On the underside of the sink unit <b>100</b> several holding elements <b>134</b> are arranged, of which respectively one extends along the two long sides <b>136</b> and respectively one extends along the two short sides <b>138</b> of the substantially rectangular sink unit <b>100</b>. Two holding elements <b>134</b> respectively terminate at a distance from one another in the rounded corner regions of the sink unit <b>100</b>.

0044It can also be provided that each of the holding elements <b>134</b> running along a side of the sink unit <b>100</b> is divided into several spaced holding element sections.

0045As may be seen from <figref idref="DRAWINGS">FIG. 3</figref>, each of these holding elements <b>134</b> has a generally C-shaped cross-section, with a horizontal upper leg <b>140</b>, a horizontal lower leg <b>142</b>, which as a result of the holding element <b>134</b> is slightly shorter in cross-section than the upper horizontal leg <b>140</b>, and a vertical web <b>144</b> joining the lower leg <b>142</b> to the upper leg <b>140</b>.

0046The upper leg <b>140</b> of the holding element <b>134</b> abuts flat against the underside of the horizontal sink edge region <b>123</b> with its upper side, wherein the transition area between the upper leg <b>140</b> and the vertical web <b>144</b> closely adjoins the underside of the inner convexly curved region <b>124</b> of the sink edge <b>122</b>.

0047In this transition region, the holding element <b>134</b> is fastened to the sink unit <b>100</b> by welding, preferably by laser welding.

0048Alternatively or additionally to welding of the holding element <b>134</b> to the sink unit <b>100</b>, it can also be provided that the holding element <b>134</b> is glued to the underside of the sink unit <b>100</b> by means of a suitable adhesive.

0049The sink unit <b>100</b> is provided to be received in a generally rectangular receiving opening <b>146</b> of a work surface <b>148</b>, said opening having a substantially vertical cut face <b>152</b>, which is directed perpendicular to the upper side <b>150</b> of the work surface <b>148</b> and which was produced by means of a compass saw, for example, and borders the receiving opening <b>146</b>.

0050The fastening of the sink unit <b>100</b> to the work surface <b>148</b> is achieved by means of a variable-volume material, as described below with reference to FIGS. <b>3</b> to <b>5</b>.

0051The variable-volume material used is a two-component polyurethane foam, for example, such as that marketed by Rampf Gieβharze GmbH &amp; Co. KG, Albstraβe 37, 72661 Grafenberg, Germany under the name RAKU-PUR® 34 (in-house name: “Hartschaum 534”).

0052In this case, one of the two components of the polyurethane foam contains the monomers to be cross-linked with one another and the other component contains an isocyanate hardener. The isocyanate hardener is overdosed therein in order to generate the two-stage expansion behaviour of the polyurethane foam described below.

0053The two components of the polyurethane foam are supplied and stored in separate receptacles and are applied simultaneously upon use of the polyurethane foam.

0054For this application a dispenser can be used, for example, which has a cylindrical exit nozzle, which is connected to a storage container for the first component, and a second exit nozzle surrounding this exit nozzle in a ring shape, which is connected to a storage container for the second component. By means of two interconnected plungers, which act on the first component and the second component, the first component and the second component of the polyurethane foam can be discharged simultaneously through the respective exit openings in a predetermined mixture ratio.

0055As may be seen from <figref idref="DRAWINGS">FIG. 3</figref>, a bead <b>154</b> of the variable-volume material is applied to the holding element <b>134</b> in the transition area between the lower leg <b>142</b> and the web <b>144</b>.

0056A film <b>156</b> of the variable-volume material is additionally applied to the cut face <b>152</b> of the work surface <b>148</b>, in which case the film <b>156</b> can be spaced both from the upper side <b>150</b> and from the underside <b>158</b> of the work surface <b>148</b>.

0057The application of the bead <b>154</b> and the film <b>156</b> can be conducted over the entire length of the holding element <b>134</b> or only over part-sections of the holding element <b>134</b>.

0058Directly after the application of the bead <b>154</b> and the film <b>156</b>, the sink unit <b>100</b> is inserted into the receiving opening <b>146</b> of the work surface <b>148</b>, wherein a gap <b>160</b> remains firstly between the outer edge <b>132</b> of the sink unit <b>100</b> on the one hand and the upper side <b>150</b> of the work surface <b>148</b> on the other hand (see <figref idref="DRAWINGS">FIG. 3</figref>). As may be additionally seen from <figref idref="DRAWINGS">FIG. 3</figref>, the thickness of the film <b>156</b> directly after application substantially corresponds to the distance of the lower leg <b>142</b> of the holding element <b>134</b> from the cut face <b>152</b>.

0059The holding element <b>134</b> faces the work surface <b>148</b> with its legs <b>140</b>, <b>142</b>, so that an expansion chamber <b>161</b> is formed between the holding element <b>134</b> and the work surface <b>148</b> for a clamping body <b>162</b> to be formed from the variable-volume material.

0060In a first curing stage, the film <b>156</b> and the bead <b>154</b> of the variable-volume material expand until the film <b>156</b> and the bead <b>154</b> combine to form an intermediate body <b>164</b>, which is integrally bonded both to the cut face <b>152</b> and to the holding element <b>134</b>.

0061The state reached after this first curing phase (after a pot life of approximately 15 minutes, for example) is shown in <figref idref="DRAWINGS">FIG. 4</figref>. In this state the outer edge <b>132</b> of the sink unit <b>100</b> and the upper side <b>150</b> of the work surface <b>148</b> are still spaced from one another.

0062In a second expansion stage following this first curing phase, a so-called “dry expansion”, which is effected, for example, by the presence of an excess of isocyanate hardener in a polyurethane foam used as variable-volume material, the intermediate body <b>164</b> expands further on all sides, which as a result of the integral bond already achieved in the first curing stage between the intermediate body <b>164</b> and the work surface <b>148</b>, on the one hand, and the holding element <b>134</b>, on the other, causes the clamping body <b>162</b> formed by full expansion of the intermediate body <b>164</b> to exert a compressive force on the upper side of the horizontal lower leg <b>140</b> (vertical compressive force F_v) and on the inside of the vertical web <b>144</b> of the holding element <b>134</b> (horizontal compressive force F_h).

0063The resultant of these compressive forces causes the holding element <b>134</b>, and with it the sink unit <b>100</b>, to which the holding element <b>134</b> is fastened, to be pulled downwards, so that the outer edge <b>132</b> of the sink unit <b>100</b> comes to abut against the upper side <b>150</b> of the work surface <b>148</b> and consequently the initially present gap <b>161</b> disappears.

0064The upper side of the upper leg <b>140</b> and the lower region of the inside of the web <b>144</b> of the holding element <b>134</b> thus form a lower contact surface <b>166</b> or an upper contact surface <b>167</b>, at which the holding element <b>134</b> is subjected to a compressive force by the clamping body <b>162</b>.

0065Because of the resultant total force acting on the holding element <b>134</b>, the sink unit <b>100</b> is fastened to the edge region of the work surface <b>148</b> and can no longer be moved upwards out of the receiving opening <b>146</b>.

0066In an alternative embodiment of the fastening of the sink unit <b>100</b> to the work surface <b>148</b>, it can be provided that the dimensionally variable material is only applied to the holding element <b>134</b> and not to the cut face <b>152</b> of the work surface <b>148</b>. In this case, the dimensionally variable material expands from the holding element <b>134</b> to the cut face <b>152</b> and there forms an integral bond with the work surface <b>148</b>.

0067As already mentioned, the bead <b>154</b> and the film <b>156</b> can be applied circumferentially around the edge of the receiving opening <b>146</b> or only in sections.

0068In the further embodiment of a fastening of the sink unit <b>100</b> to the work surface <b>148</b> shown in <figref idref="DRAWINGS">FIG. 6</figref>, the upper leg <b>140</b> of the holding element <b>134</b> is not straight, but convexly curved (viewed from its upper side <b>169</b>).

0069In the state shown in <figref idref="DRAWINGS">FIG. 6</figref>, in which the clamping body <b>162</b> is fully expanded, the edge <b>168</b> of the upper leg <b>140</b> on the work surface side is thus supported on the upper side <b>150</b> of the work surface <b>148</b>, and thus acts as a torque stop, which compensates the torque, which is exerted on the holding element <b>134</b> as a result of the compressive force F_Hfrom the clamping body <b>162</b> acting on the lower section of the inside of the web <b>144</b> of the holding element <b>134</b>.

0070This torque is directed such that it endeavours to rotate the holding element <b>134</b> around the edge <b>170</b> between the upper leg <b>140</b> and the web <b>144</b>, along which the holding element <b>134</b> is fastened to the underside of the sink unit <b>100</b> by welding (counter-clockwise as seen in the viewing direction of <figref idref="DRAWINGS">FIG. 6</figref>).

0071The counter-torque generated by the upper leg <b>140</b> acting as torque stop prevents the lower section of the holding element <b>134</b> from being bent still further into the interior of the receiving opening <b>146</b> than is shown in <figref idref="DRAWINGS">FIG. 6</figref>.

0072Otherwise, this further embodiment has the same structure and function as the embodiment explained above with reference to FIGS. <b>3</b> to <b>5</b>.

0073The embodiment of a fastening of the sink unit <b>100</b> to the work surface <b>148</b> shown in FIGS. <b>7</b> to <b>9</b> differs from the embodiment shown in FIGS. <b>3</b> to <b>5</b> in that besides a substantially horizontal section <b>172</b>, the upper leg <b>140</b> of the holding element <b>134</b> also comprises a section <b>174</b> inclined towards the horizontal, which is joined to the edge of the horizontal section <b>172</b> on the work surface side via a (viewed from above) convexly curved transition section <b>176</b>.

0074In this embodiment the holding element <b>134</b> is not fastened to the inner convexly curved region <b>124</b> of the sink unit <b>100</b> but instead is fastened by welding to the outer convexly curved region <b>128</b> of the sink edge <b>122</b> in the region of the convexly curved transition section <b>176</b>.

0075As a result of the weld being shifted into the region of the outer convexly curved region <b>128</b> of the sink edge <b>122</b>, the horizontal section <b>172</b> of the upper leg <b>140</b>, which abuts flat against the underside of the horizontal sink edge region <b>123</b>, forms a torque stop against a rotation of the holding element <b>134</b> (counter-clockwise as seen in the viewing direction of <figref idref="DRAWINGS">FIG. 7</figref>) around the convexly curved transition section <b>176</b>, at which the holding element <b>134</b> is fastened to the sink unit <b>100</b>.

0076Alternatively or additionally to a shift of the weld into the outer convexly curved region <b>128</b> of the sink edge <b>122</b>, an additional support element could also be provided on the outside of the web <b>144</b> of the holding element <b>134</b> facing the sink unit <b>100</b>.

0077In the fastening method shown in FIGS. <b>7</b> to <b>9</b>, the film <b>156</b> of the variable-volume material is applied beyond the entire cut face <b>152</b> and the edges of the cut face <b>152</b> towards the upper side <b>150</b> and the underside <b>158</b> of the work surface <b>148</b>, so that the cut face <b>152</b> of the work surface <b>148</b> is sealed by the dimensionally variable material and the work surface <b>148</b> (comprising a particle board, for example) is protected against the penetration of water from the cut face <b>152</b>.

0078As a result, it is no longer necessary to additionally seal the cut face <b>152</b>, e.g. by means of a silicone material. Instead, the same dimensionally variable material as used to form the clamping body <b>162</b> can be used for the sealing.

0079After application of the bead <b>154</b> and the film <b>156</b> and insertion of the sink unit <b>100</b> into the receiving opening <b>146</b>, the film <b>156</b> and the bead <b>154</b> expand and combine to form the intermediate body <b>164</b> shown in <figref idref="DRAWINGS">FIG. 8</figref>, which is integrally bonded to the work surface <b>148</b> and the holding element <b>134</b>.

0080As a result of a further “dry” expansion, the clamping body <b>162</b> shown in <figref idref="DRAWINGS">FIG. 9</figref> is formed from this intermediate body <b>164</b>, and this clamping body exerts a compressive force F_vdirected vertically downwards on the lower contact surface <b>166</b> of the holding element <b>134</b> and a horizontal compressive force F_Hdirected into the interior of the receiving opening <b>146</b> on the upper contact surface <b>167</b> of the holding element <b>134</b>.

0081The torque exerted on the holding element <b>134</b> through the horizontal compressive force is compensated by the horizontal section <b>172</b> of the upper leg <b>140</b> acting as a torque stop, which is supported on the horizontal sink edge region <b>123</b>, while the vertical compressive force acting on the lower leg <b>142</b> pulls the holding element <b>134</b> and with it the sink edge <b>122</b> downwards, so that the outer edge <b>132</b> of the sink unit <b>100</b> comes into abutment against the upper side <b>150</b> of the work surface <b>148</b>.

0082Otherwise, the embodiment shown in FIGS. <b>7</b> to <b>9</b> has the same structure and function as the embodiment illustrated above with reference to FIGS. <b>3</b> to <b>5</b>.

0083The further embodiment of a fastening of the sink unit <b>100</b> to the work surface <b>148</b> shown in FIGS. <b>10</b> to <b>12</b> differs from the embodiment shown in FIGS. <b>3</b> to <b>5</b> in that the cut face <b>152</b> of the work surface <b>148</b> does not run vertically, but is inclined towards the vertical such that the receiving opening <b>146</b> in the work surface <b>148</b> widens from the upper side <b>150</b> towards the underside <b>158</b> of the work surface <b>148</b>.

0084Moreover, the amount of variable-volume material used is selected so that the expansion chamber <b>161</b> formed between the holding element <b>134</b> and the work surface <b>148</b> is filled to more than approximately 50% of its volume by the fully expanded clamping body <b>162</b> (see <figref idref="DRAWINGS">FIG. 12</figref>).

0085In order to prevent the variable-volume material from discharging upwards out of the expansion chamber <b>161</b> during its expansion, the holding element <b>134</b> comprises an upper leg <b>140</b> with a horizontal section <b>172</b>, which merges via a convexly curved transition section <b>176</b> into a substantially vertical section <b>178</b>, which is pulled towards the upper side <b>150</b> of the work surface <b>148</b> during the expansion of the clamping body <b>162</b>, and thus closes off the expansion chamber <b>161</b> formed between the holding element <b>134</b> and the work surface <b>148</b> at its upper end.

0086In this embodiment, a bead <b>154</b> of the variable-volume material is applied to the upper side of the lower leg <b>142</b> and the inside of the web <b>144</b> of the holding element <b>134</b>.

0087After insertion of the sink unit <b>100</b> into the receiving opening <b>146</b>, the variable-volume material expands on curing until it comes into contact with the inclined cut face <b>152</b> of the work surface <b>148</b> and integrally bonds with this (see <figref idref="DRAWINGS">FIG. 11</figref>).

0088In the second “dry” expansion stage, the variable-volume material expands further until the clamping body <b>152</b> shown in <figref idref="DRAWINGS">FIG. 12</figref> is formed, which fills the expansion chamber <b>161</b> almost completely.

0089Because an expansion chamber <b>161</b>, which is filled to more than 50% of its volume by the clamping body <b>162</b>, is provided in this embodiment, the structure of the clamping body <b>162</b> can be better controlled at least in its upper section than would be the case with a freely expanding foam.

0090Because the cut face <b>152</b> is inclined such that its normal is directed obliquely downwards, the resultant reaction force acting on the clamping body <b>162</b> from the work surface <b>148</b> is also directed downwards with the result that the horizontal compressive force F_Hacting on the inside of the web <b>144</b> decreases in favour of the vertical compressive force F_vacting on the upper side of the lower leg <b>142</b> and therefore the resultant compressive force exerted on the holding element <b>134</b> by the clamping body <b>162</b> is directed more steeply downwards than in an embodiment, in which the cut face <b>152</b> is oriented vertically.

0091Therefore, an orientation of the cut face <b>152</b> inclined towards the vertical is of advantage in all embodiments of the fastening of the sink unit <b>100</b> to the work surface <b>148</b>.

0092Otherwise, the embodiment shown in FIGS. <b>10</b> to <b>12</b> has the same structure and function as the embodiment described above with reference to FIGS. <b>3</b> to <b>5</b>.

0093The embodiment of a fastening of the sink unit <b>100</b> to the work surface <b>148</b> shown in <figref idref="DRAWINGS">FIG. 13</figref> differs from the embodiment shown in FIGS. <b>3</b> to <b>5</b> in that the web <b>144</b> of the holding element <b>134</b> is not oriented vertically, but is inclined towards the vertical such that the lower edge of the web is at a greater distance from the work surface <b>148</b> than the upper edge.

0094Moreover, the lower leg <b>142</b> of the holding element <b>134</b> is not horizontally oriented, but is inclined towards the horizontal such that its edge <b>180</b> on the work surface side lies at a lower level than the transition region to the web <b>144</b>.

0095As a result of this structure of the holding element <b>134</b>, the transition region between the web <b>144</b> and the lower leg <b>142</b> of the holding element <b>134</b> forms a lug <b>182</b> projecting into the interior of the receiving opening <b>146</b>.

0096In this embodiment, the upper leg <b>140</b> of the holding element <b>134</b> is not straight, but is convexly curved (viewed from the upper side of the upper leg <b>140</b>).

0097In this embodiment, the expansion chamber <b>161</b> configured between the holding element <b>134</b> and the work surface <b>148</b> is substantially completely filled by the fully expanded clamping body <b>162</b>.

0098In this case, the circumstance that the lower contact surface <b>166</b> formed by the upper side of the lower leg <b>142</b> of the holding element <b>134</b> is clearly larger than the underside of the upper leg <b>140</b> ensures that the resultant compressive force exerted by the clamping body <b>162</b> on the holding element <b>134</b> is directed downwards and therefore pulls the sink edge <b>122</b> down towards the upper side of the work surface <b>148</b>.

0099Otherwise, the embodiment shown in <figref idref="DRAWINGS">FIG. 13</figref> has the same structure and function as the embodiment described above with reference to FIGS. <b>3</b> to <b>5</b>.

0100A further embodiment of a fastening of the sink unit <b>100</b> to the work surface <b>148</b> shown in FIGS. <b>14</b> to <b>15</b> differs from the embodiment shown in FIGS. <b>3</b> to <b>5</b> in that a support element in the form of a support strip <b>184</b> running along the edge of the receiving opening <b>146</b> is provided on the upper side <b>150</b> of the work surface <b>148</b>.

0101The support strip <b>184</b> comprises a horizontal holding section <b>186</b>, with which the support strip <b>184</b> is fastened to the upper side <b>150</b> of the work surface <b>148</b>, e.g. by gluing and/or by means of screws or nails, and a support section <b>188</b> projecting obliquely upwards from the holding section <b>186</b> on the edge of the receiving opening <b>146</b>.

0102In order to prevent a collision with the support section <b>188</b> of the support strip <b>184</b>, the upper leg <b>140</b> of the holding element <b>134</b> is configured shorter in this embodiment than in the embodiment shown in FIGS. <b>3</b> to <b>5</b>.

0103The holding element <b>134</b>, the support strip <b>184</b> and the work surface <b>148</b> form an expansion chamber <b>161</b> between them, which is substantially completely filled by the fully expanded clamping body <b>162</b>.

0104In the fully expanded state shown in <figref idref="DRAWINGS">FIGS. 14 and 15</figref>, the clamping body <b>162</b> is supported on the support section <b>188</b> of the support strip <b>184</b>, which leads to a reaction force that is directed obliquely downwards acting on the clamping body <b>162</b> from the support strip <b>184</b>.

0105This reaction force is transferred from the clamping body <b>162</b> to the holding element <b>134</b>, which increases the vertically downward directed component of the compressive force exerted by the clamping body <b>162</b> on the holding element <b>134</b>, so that the clamping force pulling the sink edge <b>122</b> towards the upper side <b>150</b> of the work surface <b>148</b> is increased.

0106In order to increase the reaction force acting on the clamping body <b>162</b> from the support section <b>188</b>, it can be provided that the support strip <b>184</b> is provided with a spring element, which prestresses the support section <b>188</b> down towards the clamping body <b>162</b>.

0107Otherwise, the embodiment shown in <figref idref="DRAWINGS">FIGS. 14 and 15</figref> has the same structure and function as the embodiment illustrated above with reference to FIGS. <b>3</b> to <b>5</b>.

0108A further embodiment of a fastening of the sink unit <b>100</b> to the work surface <b>148</b> shown in FIGS. <b>16</b> to <b>17</b> differs from the embodiment shown in FIGS. <b>3</b> to <b>5</b> in that the lower leg <b>142</b> of the holding element <b>134</b> is not oriented substantially horizontally, but is oriented obliquely upwards, and that is in such a manner that the edge <b>180</b> of the lower leg <b>142</b> on the work surface side lies at a higher level than its edge remote from the work surface <b>148</b>, at which the lower leg <b>142</b> merges into the web <b>144</b> of the holding element <b>134</b>.

0109As a result of this configuration, the lower leg <b>142</b> forms a blade guide for a cutting blade <b>190</b>, which is inserted from below into the gap between the edge <b>180</b> of the lower leg <b>142</b> on the work surface side, on one side, and the cut face <b>152</b> of the work surface <b>148</b>, on the other side, and by means of said blade the clamping body <b>162</b> arranged between the cut face <b>152</b> and the holding element <b>134</b> can be cut through and/or detached from the work surface <b>148</b> in order to sever the connection between the holding element <b>134</b> and the work surface <b>148</b> and then the sink unit <b>100</b> can be lifted upwards out of the receiving opening <b>146</b>.

0110The cutting blade <b>190</b> is guided on one side by the insertion slope formed by the lower leg <b>142</b> and on the other side by the straight cut face <b>152</b> for a cut running around the receiving opening <b>146</b>.

0111Otherwise, the embodiment shown in <figref idref="DRAWINGS">FIGS. 16 and 17</figref> has the same structure and function as the embodiment described above with reference to FIGS. <b>3</b> to <b>5</b>.

0112An embodiment of a fastening of the sink unit <b>100</b> to the work surface <b>148</b> shown in FIGS. <b>18</b> to <b>21</b> differs from the embodiment shown in FIGS. <b>3</b> to <b>5</b> in that the lower leg <b>142</b> of the holding element <b>134</b> is not oriented horizontally but obliquely downwards, and that is in such a manner that the edge <b>180</b> of the lower leg <b>142</b> on the work surface side lies at a lower level than its edge remote from the work surface <b>148</b>, at which the lower leg <b>142</b> merges into the web <b>144</b> of the holding element <b>134</b>.

0113As a result of this structure of the lower leg <b>142</b>, this serves as a guide for a separating element in the form of a metal wire <b>192</b>, which is arranged in the expansion chamber <b>161</b> above the clamping body <b>162</b> and to cut through the clamping body <b>162</b> can be pulled down through the gap between the edge <b>180</b> of the lower leg <b>142</b> of the holding element <b>134</b> on the work surface side on one side and the cut face <b>152</b> of the work surface <b>148</b> on the other side.

0114The metal wire <b>192</b> extends in the longitudinal direction of the holding element <b>134</b> and is enclosed by a tubular sheath <b>194</b>, which is made of paper, for example.

0115Before assembly of the sink unit <b>100</b> on the work surface <b>148</b>, the sheath <b>194</b> containing the metal wire <b>192</b> is fastened to the transition region between the upper leg <b>140</b> and the web <b>144</b> of the holding element <b>134</b>, e.g. by gluing.

0116As is shown in <figref idref="DRAWINGS">FIGS. 20 and 21</figref>, the separating element formed by the metal wire <b>192</b> runs around through all the holding elements <b>134</b> arranged on the sink edge <b>122</b>, in which case at the corner regions of the sink edge <b>122</b> the separating element respectively exits from one holding element <b>134</b> and enters the adjacent holding element <b>134</b>.

0117As may be seen from <figref idref="DRAWINGS">FIG. 19</figref>, one of the holding elements <b>134</b> is broken at one location <b>196</b>, wherein on both sides of the break location <b>196</b> a respective end region <b>198</b> of the metal wire <b>192</b> exits from the holding element <b>134</b>.

0118Each of the end regions <b>198</b> of the metal wire <b>192</b> is respectively provided with an operating element <b>200</b> in the form of a pull ring.

0119In order to cut through the clamping body <b>162</b>, the end regions <b>198</b> of the metal wire <b>192</b> are pulled downwards by means of the operating elements <b>200</b>, as a result of which the metal wire <b>192</b> breaks through its sheath <b>194</b> and cuts through the clamping body <b>162</b> from top to bottom, wherein the lower leg <b>142</b> of the holding element <b>134</b> serves as exit slope for the metal wire <b>192</b>.

0120As a result of cutting through the clamping body <b>162</b>, the connection between the work surface <b>148</b> and the holding element <b>134</b> is broken, so that the sink unit <b>100</b> can then be lifted up out of the receiving opening <b>146</b>.

0121Otherwise, the embodiment shown in FIGS. <b>18</b> to <b>21</b> has the same structure and function as the embodiment described above with reference to FIGS. <b>3</b> to <b>5</b>.

0122A further embodiment of a fastening of the sink unit <b>100</b> to the work surface <b>148</b> shown in FIGS. <b>22</b> to <b>24</b> differs from the embodiment shown in FIGS. <b>3</b> to <b>5</b> in that the variable-volume material is not applied directly onto the holding element <b>134</b> and/or the work surface <b>148</b>, but is arranged instead in a flexible sheath <b>202</b> in the form of a tube.

0123The tube can be made of a plastic material, e.g. polyvinyl chloride.

0124As may be seen best from <figref idref="DRAWINGS">FIG. 23</figref>, a two-component foam is used in this embodiment, its first component <b>204</b> being arranged inside the flexible sheath <b>202</b>.

0125The second component <b>206</b> is arranged inside a capsule <b>208</b>, which is connected to an operating element <b>212</b> in the form of a pull ring by means of a pull cord <b>210</b>, which is fastened to an end of the capsule <b>208</b>.

0126The pull cord <b>210</b> is passed through the interior of the flexible sheath <b>202</b> of the first component <b>204</b>, so that the capsule <b>208</b> can be pulled through the first component <b>204</b> of the variable-volume material contained in the flexible sheath <b>202</b> by pulling on the pull cord <b>210</b> by means of the operating element <b>212</b>.

0127On the side of the capsule <b>208</b> lying at the front in pulling direction, an opening <b>213</b> is provided, through which a part of the first component <b>204</b> penetrates into the interior of the capsule <b>208</b> as the capsule <b>208</b> is pulled through the first component <b>204</b>, and the second component <b>206</b> of the variable-volume material is displaced through an opening <b>214</b> in the capsule <b>208</b> located opposite the opening <b>213</b> and into the outer area of the capsule <b>208</b>, where a curing reaction and therefore an expansion of the variable-volume material is activated by the contact between the first component <b>204</b> and the second component <b>206</b> of the variable-volume material, so that the variable-volume material expands to form the clamping body <b>162</b> with approximately circular cross-section shown in <figref idref="DRAWINGS">FIG. 24</figref>.

0128Upon this expansion the flexible sheath <b>202</b> becomes taut, so that it assumes the substantially cylindrical form shown in <figref idref="DRAWINGS">FIG. 24</figref>.

0129The fully expanded clamping body <b>162</b>, which is supported on the cut face <b>152</b> of the work surface <b>148</b>, exerts compressive forces on the inside of the web <b>144</b> and on the upper side of the lower leg <b>142</b> of the holding element <b>134</b>, which form a resultant force, which is directed such that the holding element <b>134</b> is pulled downwards and the outer edge <b>132</b> of the sink edge <b>122</b> of the sink unit <b>100</b> comes into abutment against the upper side <b>150</b> of the work surface <b>148</b>.

0130The cut face <b>152</b> of the work surface <b>148</b> is inclined towards the vertical such that the receiving opening <b>146</b> widens from the upper side <b>150</b> of the work surface <b>148</b> towards the underside <b>158</b> thereof. As a result, the normal of the cut face <b>152</b> of the work surface <b>148</b> is inclined downwards, and therefore the reaction force exerted by the work surface <b>148</b> on the clamping body <b>162</b> is also directed obliquely downwards. This increases the component of the compressive force directed vertically downwards, which the clamping element <b>162</b> exerts on the holding element <b>134</b>.

0131The activation of the variable-volume material by operating the pull cord <b>210</b> occurs after the sink unit <b>100</b> has been inserted into the receiving opening <b>146</b> of the work surface <b>148</b>.

0132Otherwise, the embodiment shown in FIGS. <b>22</b> to <b>24</b> has the same structure and function as the embodiment described above with reference to FIGS. <b>3</b> to <b>5</b>.

0133A further embodiment of a fastening of the sink unit <b>100</b> to the work surface <b>148</b> shown in FIGS. <b>25</b> to <b>27</b> differs from the embodiment shown in FIGS. <b>3</b> to <b>5</b> in that in the expansion chamber <b>161</b> formed between the holding element <b>134</b> and the work surface <b>148</b> an expansion restricting body <b>214</b> is arranged, which substantially covers the entire horizontal cross-section of the expansion chamber <b>161</b>, and during the expansion of the variable-volume material applied to the holding element <b>134</b> in the form of a bead <b>154</b>, is displaced with low reaction force by the expanding variable-volume material via the intermediate body <b>164</b> as far as the clamping body <b>162</b>.

0134The expansion restricting body <b>214</b> prevents the variable-volume material from discharging upwards out of the expansion chamber <b>161</b>.

0135Moreover, the expansion restricting body <b>214</b> prevents upwardly directed compressive forces from acting on the installation element <b>100</b>.

0136Moreover, the upper boundary face of the clamping body <b>162</b> formed by the expansion is uniformly controlled, and therefore the structure of the clamping body <b>162</b> is better controlled.

0137The expansion restricting body <b>214</b> is preferably made of a material, which disintegrates or chemically decomposes upon contact with the variable-volume material, or which is substantially plastically deformed by the expanded variable-volume material without transferring compressive forces onto the upper leg <b>140</b> of the holding element <b>134</b>.

0138For example, it can be provided that the expansion restricting body <b>214</b> is formed from polystyrene.

0139Before insertion of the sink unit <b>100</b> into the receiving opening <b>146</b> of the work surface <b>148</b>, the expansion restricting body <b>214</b> is fastened to the underside of the upper leg <b>140</b> and/or to the inside of the web <b>144</b> of the holding element <b>134</b>, e.g. by gluing.

0140Otherwise, the embodiment shown in FIGS. <b>25</b> to <b>27</b> has the same structure and function as the embodiment described above with reference to FIGS. <b>3</b> to <b>5</b>.

0141A separating element, e.g. a metal wire, for cutting through the clamping body <b>162</b> for removal of the sink unit <b>100</b> from the receiving opening <b>146</b> of the work surface <b>148</b> can be embedded in the expansion restricting body <b>214</b> or arranged on the surface of the expansion restricting body <b>214</b>.

0142A further embodiment of a fastening of the sink unit <b>100</b> to the work surface <b>148</b> shown in FIGS. <b>28</b> to <b>30</b> differs from the embodiment shown in FIGS. <b>18</b> to <b>21</b> in that the holding element <b>134</b> of this embodiment does not have a lower leg <b>142</b>.

0143The variable-volume material is applied in the form of a bead <b>154</b> onto the lower region of the inside of the web <b>144</b> of the generally L-shaped holding element <b>134</b> and in the form of a film <b>156</b> onto the cut face <b>152</b> of the work surface <b>148</b>.

0144Directly after application of the variable-volume material, the sink unit <b>100</b> is inserted into the receiving opening <b>146</b> of the work surface <b>148</b>.

0145In a first curing phase, the bead <b>154</b> and the film <b>156</b> expand until these combine to form an intermediate body <b>164</b>, which is shown in <figref idref="DRAWINGS">FIG. 29</figref>, and is integrally bonded to the cut face <b>152</b> of the work surface <b>148</b> and to the web <b>144</b> of the holding element <b>134</b>.

0146In the subsequent “dry” expansion phase the holding element <b>134</b> is pulled downwards, as a result of which the outer edge <b>132</b> of the sink edge <b>122</b> comes into abutment against the upper side <b>150</b> of the work surface <b>148</b>.

0147The fastening of the sink unit <b>100</b> to the work surface <b>148</b> is thus concluded.

0148To release the sink unit <b>100</b> from the work surface <b>148</b> there serves, as in the embodiment shown in FIGS. <b>18</b> to <b>21</b>, a separating element, e.g. in the form of a metal wire <b>192</b> provided with a tubular paper sheath <b>194</b>, which extends along the holding element <b>134</b> and is fastened, e.g. by gluing, above the clamping body <b>162</b> to the upper leg <b>140</b> and/or to the web <b>144</b> of the holding element <b>134</b>.

0149Otherwise, the embodiment shown in FIGS. <b>28</b> to <b>30</b> has the same structure and function as the embodiment described above with reference to FIGS. <b>18</b> to <b>21</b>.

0150A further embodiment of a fastening of the sink unit <b>100</b> to the work surface <b>148</b> shown in <figref idref="DRAWINGS">FIGS. 31 and 32</figref> differs from the embodiment shown in FIGS. <b>3</b> to <b>5</b> in that the web <b>144</b> of the holding element <b>134</b> is not oriented vertically, but is inclined towards the vertical, and that is in such a manner that a lower edge of the web <b>144</b> is at a greater distance from the cut face <b>152</b> of the work surface <b>148</b> than an upper edge thereof.

0151Moreover, the lower leg <b>142</b> of the holding element <b>134</b> is not oriented horizontally, but is inclined towards the horizontal, and that is in such a manner that an edge <b>180</b> of the lower leg <b>142</b> on the work surface side is arranged at a lower level than an edge of the lower leg <b>142</b> remote from the work surface <b>148</b>, at which the lower leg <b>142</b> merges into the web <b>144</b>.

0152As a result of this configuration of the web <b>144</b> and the lower leg <b>142</b>, a lug <b>182</b> projecting into the interior of the receiving opening <b>146</b> is configured on the holding element <b>134</b> in the transition region of the web <b>144</b> and the lower leg <b>142</b>.

0153Moreover, on the cut face <b>152</b> of the work surface <b>148</b> in this embodiment, a support strip <b>184</b> is arranged, which comprises an upper holding section <b>186</b>, which abuts flat against the cut face <b>152</b> and is fastened to this—by gluing and/or by means of suitable fastening elements such as screws and/or nails, for example,—and also a support section <b>188</b>, which projects obliquely downwards from the holding section <b>186</b> and which is pivoted to the holding section <b>186</b> via a hinge <b>216</b>.

0154Moreover, a spring element <b>218</b> is provided on the support strip <b>184</b>, which prestresses the support section <b>188</b> of the support strip <b>184</b> towards the cut face <b>152</b> of the work surface <b>148</b>.

0155In this embodiment the variable-volume material is applied as a bead <b>154</b> between the face <b>152</b> and the support section <b>188</b> of the support strip <b>184</b>.

0156Directly after the variable-volume material is applied, the sink unit <b>100</b> is inserted into the receiving opening <b>146</b> of the work surface <b>148</b>, as shown in <figref idref="DRAWINGS">FIG. 31</figref>.

0157The variable-volume material then expands against the restoring force of the spring element <b>218</b> to form the clamping body <b>162</b> shown in <figref idref="DRAWINGS">FIG. 32</figref>, which exerts a resultant compressive force on the holding element <b>134</b>, which causes the holding element <b>134</b> to be pulled downwards and the outer edge <b>132</b> of the sink unit <b>100</b> to come into abutment against the upper side <b>150</b> of the work surface <b>148</b>.

0158In the fully expanded state of the clamping body <b>162</b>, a free edge <b>220</b> of the support section <b>188</b> of the support strip <b>184</b> abuts against the inside of the web <b>144</b> of the holding element <b>134</b>, so that the holding element <b>134</b> serves as a stop for the support section <b>188</b>, which prevents the support section <b>188</b> from pivoting further upwards.

0159Therefore, in this stop position the support section <b>188</b> of the support strip <b>184</b> restricts the upward expansion of the clamping body <b>162</b>.

0160Moreover, because of the restoring force of the spring element <b>218</b>, the support section <b>188</b> exerts a compressive force on the clamping body <b>162</b>, which is directed obliquely downwards towards cut face <b>152</b> of the work surface <b>148</b> and which causes the horizontal component of the compressive force exerted by the clamping body <b>162</b> on the holding element <b>134</b> to decrease and the component of the compressive force exerted by the clamping body <b>162</b> on the holding element <b>134</b> to increase.

0161Otherwise, the embodiment shown in <figref idref="DRAWINGS">FIGS. 31 and 32</figref> has the same structure and function as the embodiment described above with reference to FIGS. <b>3</b> to <b>5</b>.

0162From the foregoing, persons of ordinary skill in the art will readily appreciate that methods have been provided which enable an installation element to be fastened simply and quickly to a work surface.

0163An illustrated example method for fastening an installation element, in particular a sink, to the edge of a receiving opening for the installation element, wherein the installation element has at least one holding element, includes: <ul id="ul0001" list-style="none"><li id="ul0001-0001" num="0000"><ul id="ul0002" list-style="none"><li id="ul0002-0001" num="0164"> arranging a variable-volume material on the installation element and/or on the holding element and/or on the work surface and/or between the installation element and the work surface; </li><li id="ul0002-0002" num="0165"> arranging the installation element in the receiving opening of the work surface; </li><li id="ul0002-0003" num="0166"> changing the volume of the variable-volume material, so that a clamping body is formed from the variable-volume material, which exerts a resultant force on the holding element of the installation element, which causes the installation element to be pulled towards the work surface. </li></ul></li></ul>

0167Arranging the variable-volume material on the installation element, on the holding element and/or on the work surface and/or between the installation element and the work surface, on the one hand, and arranging the installation element in the receiving opening of the work surface, on the other hand, can be conducted therein in any desired sequence.

0168In particular it is also conceivable that part of the variable-volume material is arranged on the installation element, on the holding element and/or on the work surface, that the installation element is then arranged in the receiving opening of the work surface, and that a further part of the variable-volume material is then arranged on the installation element, on the holding element and/or on the work surface and/or between the installation element and the work surface.

0169The holding element can be configured in one piece with the installation element, or alternatively thereto can be configured as a separate part from the installation element that is joined to the installation element.

0170A “variable-volume material” is understood in this description and the attached claims to be a material, which undergoes directly or indirectly, in particular by chemical reaction, a preferably irreversible change in volume, which is greater than a thermal expansion of the material possibly occurring as a result of a change in the ambient temperature.

0171A disclosed example solution is based on the concept, wherein the holding element joined to the installation element is not latched to a holding clamp arranged on the edge of the receiving opening, but instead a clamping body is formed from the variable-volume material, which exerts a downwardly directed resultant force on the holding element, which clamps the installation element to the work surface.

0172The clamping body is preferably a solid body, so that it can transfer compressive, shearing and/or tensile forces onto the holding element.

0173This concept has the advantage that the outer edge of the installation element can lie on the work surface substantially without any gap or at least with a slight gap, since the vertical distances that can be achieved between the installation element and the work surface are not predetermined by distinct latching steps.

0174Moreover, the final structure of the clamping body is not yet determined before the change in volume of the variable-volume material, and therefore the clamping body can adapt to the respective local distance between the edge of the work surface, on the one hand, and the holding element, on the other, and in this way cutting tolerances of the receiving opening of the work surface can be compensated.

0175In addition, this concept has the advantage that no holding clamps or similar fastening elements need to be prefabricated and fastened to the edge of the receiving opening before the installation element is arranged in the receiving opening.

0176Moreover, automatic centring of the installation element in the receiving opening can be achieved when the variable-volume material expands uniformly.

0177If the variable-volume material is arranged on the installation element and/or on the holding element and/or on the work surface before arranging the installation element in the receiving opening of the work surface, then the entire assembly of the installation element on the work surface can be conducted from above the work surface without it being necessary for the installer to enter the space below the work surface to perform one or more assembly steps.

0178If a holding element is used, which is not configured in one piece with the installation element, then the holding element is advantageously fastened to the installation element before arrangement of the variable-volume material.

0179In a preferred configuration, an expandable material is used as variable-volume material. By allowing the expandable material to expand a clamping body is formed from the expandable material, which exerts a resultant compressive force on the holding element of the installation element, which causes the installation element to be pulled towards the work surface.

0180A foamable material can used in particular as expandable material.

0181Such a foamable material can contain constituents, for example, which discharge gas and thus cause expansion of the material.

0182In particular, the foamable material can contain microspheres, which are filled with such gas-discharging constituents and increase in volume during the gas discharge until they reach their final volume.

0183In a preferred configuration, a plastic foam, preferably a two-component plastic foam, in particular a two-component polyurethane foam, is used as foamable material.

0184A suitable 2-component polyurethane foam is, for example, the hard foam marketed under the name RAKU-PUR® 34 of Rampf Gieβharze GmbH &amp; Co. KG, Albstraβe 37, 72661 Grafenberg, Germany.

0185In particular, it can be provided that the expandable material expands to its final volume in at least two consecutive stages.

0186Such a two-stage expansion can be effected, for example, by overdosing a hardener component in relation to a component of the expandable material to be cured.

0187In this case, it can be provided that in a first expansion stage, the expandable material forms an integral bond with the work surface and/or with the holding element.

0188In addition, it can be provided that the clamping body is bonded integrally and/or positively with the work surface and/or with the holding element. The transfer of compressive and/or tensile forces from the clamping body to the holding element is facilitated by the adhesion of the clamping body to the holding element. Similarly, the transfer of reaction forces from the work surface to the clamping body is facilitated by the adhesion of the clamping body to the work surface.

0189In a particular configuration of a disclosed example method, it is provided that a cut face of the work surface facing the receiving opening for the installation element is sealed by the clamping body. The work surface is often configured as a particle board and is thus sensitive to moisture. Because the cut face of the work surface is sealed by means of the variable-volume material there is no necessity to seal the cut face of the work surface against the penetration of water from the receiving opening into the work surface in an additional work cycle using a separate sealing material, e.g. a silicone material.

0190In order to apply the force from the clamping body to the holding element necessary to clamp the installation element on the work surface, a holding element is advantageously used that has a contact surface, which is subjected by the clamping body to a compressive force, which has a downwardly directed component.

0191In the assembled state of the installation element, this contact surface can be oriented substantially horizontally or be inclined towards the horizontal.

0192A particularly favourable transfer of compressive forces from the clamping body to the holding element is achieved, if a holding element is used that has a contact surface, of which the edge on the work surface side lies at a lower level than the edge remote from the work surface in the assembled state of the installation element.

0193To achieve an effective support of the holding element on the installation element, a holding element is advantageously used, which abuts flat against the underside of the installation element. This is particularly advantageous if the abutment of the holding element enables support of the introduced torque or tensile forces.

0194In particular, it can be provided that the holding element abuts against a sloping edge of the installation element.

0195The holding element can be welded and/or glued onto the installation element.

0196In order to prevent excessive tilting or deformation of the holding element as a result of forces acting in horizontal direction on the holding element, a holding element can be used, which has a support, which is supported on the work surface when the holding element is subjected by the clamping body to a force directed in horizontal direction into the interior of the receiving opening.

0197The holding element is advantageously fastened to the installation element in the region of a bend line, and is preferably welded to the installation element.

0198In particular it can be provided that the holding element is fastened, preferably welded, to the installation element in the region of a bend line between a sloping edge and a substantially horizontal edge region of the installation element.

0199It is particularly advantageous if a holding element is used, which comprises a leg with a section pointing towards the work surface, and the holding element is fastened, preferably welded, to the installation element in the region of this section. Advantageous leverage and moment ratios are achieved as a result of this.

0200To enable the final structure of the clamping body to be predetermined as accurately as possible, it can be provided that the clamping body partially fills an expansion chamber defined on one side by the holding element and on the other side by the work surface, preferably to approximately 50% to approximately 90% of the volume of the expansion chamber.

0201In order to prevent penetration of the variable-volume material into the edge region of the installation element, which lies on the work surface, it can be provided that the variable-volume material expands in an expansion chamber defined on one side by the holding element and on the other side by the work surface, wherein an upper end of the expansion chamber is closed off by the holding element abutting against the work surface.

0202The receiving opening can be produced particularly easily if it is provided that an edge face of the work surface defining the receiving opening is oriented substantially vertically.

0203However, in order to generate a compressive force on the holding element, which has as large as possible a component directed vertically downwards, it can be advantageous if the edge face of the work surface defining the receiving opening is inclined towards the vertical, at least in sections.

0204To reduce the compressive force component acting on the holding element in horizontal direction and to increase the compressive force component acting downwards on the holding element, it is particularly favourable if the edge face of the work surface is inclined towards the vertical such that the receiving opening widens downwards.

0205The compressive force exerted by the clamping body on the holding element can be further increased by a support element being fastened to the work surface, against which the clamping body is supported.

0206In particular, it can be provided that the support element subjects the clamping body to a compressive force directed perpendicularly or obliquely downwards.

0207It is additionally favourable if the support element has a section projecting out from the work surface obliquely to a surface of the work surface.

0208The support element can be arranged in particular on the upper side or on the edge face of the work surface defining the receiving opening.

0209The support element can be configured, for example, as a plastic strip, which is attached on insertion of the installation element.

0210Alternatively or additionally hereto, a support element can be used that has a hinge, which is preferably prestressed towards the clamping body by means of a spring element.

0211To be able to release the installation element from the work surface again in a simple manner, it can be provided that a holding element is used, which is provided, preferably on its lower end, with a guide element for a cutting blade.

0212The guide element preferably has an insertion slope for the cutting blade to allow easy insertion of the cutting blade at a defined position.

0213After assembly of the installation element on the work surface, the clamping body can then be cut through and/or detached from the work surface or from the holding element by means of the cutting blade, so that the installation element can then be removed from the receiving opening.

0214Alternatively or additionally hereto, it can also be provided that on the installation element and/or on the holding element and/or on the work surface and/or between the installation element and the work surface a separating element is arranged, which is movable relative to the clamping body to cut through the clamping body and/or to separate the clamping body from the work surface and/or from the holding element.

0215Such a separating element can be configured as a linear element, in particular as a wire, preferably as a metal wire.

0216Several separating elements can also be provided, which are preferably arranged to overlap one another along the edge of the receiving opening.

0217To enable the separating element to be easily handled prior to its use, it can be provided that the separating element is provided with a sheath, preferably with a paper sheath.

0218In order to bring the separating element into a position above the clamping body in a simple manner for its subsequent use, the separating element and/or a sheath of the separating element can be fastened, preferably glued, to the holding element.

0219To enable the separating element to be operated simply to cut through or separate the clamping body, it is advantageous if the separating element is provided with an operating element directed out of the interstice between the holding element and the work surface.

0220The separating element is particularly simple to operate if it has one or more end regions and on each end region is provided with a respective operating element directed out of the interstice between the holding element and the work surface.

0221The variable-volume material can be applied directly onto the installation element, the holding element and/or the work surface.

0222Alternatively or additionally hereto, it can also be provided that at least part of the variable-volume material is arranged in a flexible sheath and is inserted into the interstice between the holding element and the work surface inside this flexible sheath.

0223The expansion of the variable-volume material can be better controlled by this sheath.

0224In addition, the sheath of the variable-volume material excludes any possibility of this material coming into contact with materials, which could be damaged by contact with this material. Therefore, the freedom in material choice is increased by the flexible sheath.

0225In particular, it can be provided that the variable-volume material comprises two components, which are firstly separated from one another, and that the change in volume of the variable-volume material is activated by bringing the two components in contact with one another.

0226These two components can, for example, be the two components of a two-component plastic foam.

0227In a particular configuration of a disclosed example method, it is provided that the second component is arranged inside a container, which is moved through the interior of the flexible sheath of the first component.

0228The second component can exit through an opening provided on the container into the outer area of the container, where a chemical reaction, for example, can proceed with the first component, which causes the change in volume of the variable-volume material.

0229To be able to purposefully influence the final structure of the clamping body formed from the variable-volume material and to prevent the variable-volume material from expanding into undesirable regions, e.g. into the region of the outer edge of the installation element, it can be provided that on the installation element and/or on the holding element and/or on the work surface and/or between the installation element and the work surface an expansion restricting body is arranged, the volume of which decreases on contact with the variable-volume material, preferably by plastic or elastic deformation and/or by disintegration or decomposition of the expansion restricting body.

0230The expansion restricting body preferably comprises a material, which is easily compressible without transferring high compressive force forces.

0231In particular, the expansion restricting body can contain a foam rubber material, i.e. a vulcanised latex foam based on a natural or synthetic rubber.

0232In addition, it can be provided that on the expansion restricting body or inside the expansion restricting body a separating element is arranged, which is movable relative to the clamping body to cut through the clamping body and/or to separate the clamping body from the work surface and/or from the holding element.

0233The above-described method has the further advantage that the clamping body formed from the variable-volume material can be structured so that the sealing elements usually provided between the installation element and the upper side of the work surface can be omitted.

0234Persons of ordinary skill in the art will further appreciate that installation elements of the aforementioned type, which can be fastened simply and quickly to a work surface have been disclosed.

0235A disclosed example installation element wherein a holding element has a contact surface, which on assembly of the installation element on the work surface can be subjected to a force by a clamping body formed from a variable-volume material in such a manner that the installation element is pulled towards the work surface.

0236In a preferred configuration of the installation element it is provided that the contact surface is arranged on a leg of the holding element, which projects towards the work surface.

0237It is particularly favourable if the contact surface of the holding element can be subjected by the clamping element to a compressive force directed at least partially downwards.

0238Persons of ordinary skill in the at will further appreciate that an example combination has been disclosed which comprises an installation element, in particular a sink, for fastening to the edge of a receiving opening for the installation element in a work surface, wherein the installation element has at least one holding element, and a variable-volume material, wherein the variable-volume material can be arranged on the installation element and/or on the holding element and/or on the work surface and/or between the installation element and the work surface, and the volume of the variable-volume material can be changed so that a clamping body is formed, which exerts a resultant force on the holding element of the installation element, which causes the installation element to be pulled towards the work surface when the installation element is arranged in the receiving opening of the work surface.

0239Persons of ordinary skill in the at will further appreciate that an example combination has been disclosed which comprises an installation element, in particular a sink, wherein the installation element has at least one holding element, a work surface with a receiving opening to receive the installation element and a variable-volume material, wherein the variable-volume material can be arranged on the installation element and/or on the holding element and/or on the work surface and/or between the installation element and the work surface, the installation element can be arranged in the receiving opening of the work surface, and the volume of the variable-volume material can be changed so that a clamping body is formed, which exerts a resultant force on the holding element of the installation element, which causes the installation element to be pulled towards the work surface.

0240Although certain example methods, apparatus and articles of manufacture have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents.