Abstract:
A drainage channel for embedding in a surface is disclosed. In order to ensure reliable run-off of the water even in the region remote from the outlet, the inclination of the conduit base relative to the top edge is increased in this region compared with the region close to the outlet. The channel is preferably composed of a plurality of channel bodies. In order to permit simple installation of the channel, the outer base of each channel body preferably runs parallel to its top edge.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     (a) Field of the Invention  
         [0002]     The present invention relates to a drainage channel, to a channel body, and to a combination of such channel bodies.  
         [0003]     (b) Description of the Related Art  
         [0004]     Drainage channels are frequently used in order to remove water from the surface of parking lots, roads, paths, taxiways of airports, floors in industrial halls, abattoirs or meat markets, etc. The channels are embedded in the surface, are open at the top and are usually covered with a grating. As a rule, they are composed of a plurality of prefabricated channel bodies of concrete, polyester concrete or other materials which are connected to one another at their ends. For the installation of such a channel in the foundation, it is necessary to excavate a trench, the depth of which is matched exactly to the installation depth of each channel body.  
         [0005]     In order to allow the water passing into the channel to flow off automatically, it is desirable to install the drainage channel in a slightly inclined position in the longitudinal direction in order thus to obtain a gradient. However, often the surface itself in which the channel is embedded has no gradient. In order to nonetheless enable the water to flow off, it is known to compose the drainage channel of channel bodies in which the conduit base and the outer base, running parallel to one another, of the channel body are slightly inclined relative to the top edge of the channel body. As a result, the channel has a gradient even at a horizontal surface.  
         [0006]     So that the top edge of all the channel bodies can terminate flush with the (horizontal) surface in which the channel is installed, the height of the side walls of the channel bodies, and thus their overall height, must increase continuously along the drainage channel from channel body to channel body. Such a drainage channel has been disclosed, for example, in EP-A 0 206 996. In such a channel, it is necessary to excavate a trench which continuously increases in its depth relative to the surface toward the end on the outlet side. This involves a relatively high cost and requires precise work, a factor which is not easy to comply with under the normal conditions on a building site.  
         [0007]     In such drainage channels, the gradient is often not sufficient in order to ensure a reliable run-off of the water in all the regions of the drainage channel. As a result, water and dirt residues often remain behind in the conduit, which may lead to contamination of the conduit, to unpleasant odours and in the long term to changes in the conduit material, even to leakages.  
       SUMMARY OF THE INVENTION  
       [0008]     It is therefore an object of the present invention to specify a drainage channel or individual parts of such a channel which enable the water to flow off in a reliable manner.  
         [0009]     According to a first aspect of the present invention, a drainage channel is provided which has a conduit at least partly open at the top for receiving liquid and having a conduit base, an end near an outlet, an end remote from the outlet, and a top edge, wherein the conduit base is inclined in the longitudinal direction relative to the top edge to a greater degree in a region adjoining the end remote from the outlet than in any other region of the drainage channel.  
         [0010]     According to a second aspect of the present invention, a channel body for a drainage channel is provided, the channel body having a top edge, an outer base for resting on a foundation, and a conduit section running in the longitudinal direction, open at the top and having a conduit base, wherein the conduit base, in a section which adjoins that end of the channel body at which the conduit base is at its highest, is inclined in the longitudinal direction to a greater degree relative to the top edge than in a section adjoining the opposite end of the channel body.  
         [0011]     According to a third aspect of the present invention, a channel body for a drainage channel is provided, the channel body having a top edge, an outer base for resting on a foundation, and a conduit section running in the longitudinal direction, open at the top and having a conduit base, wherein the conduit base is inclined in the longitudinal direction relative to the outer base, and wherein the outer base runs in the longitudinal direction essentially parallel to the top edge.  
         [0012]     According to a fourth aspect of the present invention, a combination of channel bodies is provided, wherein the top edge of each channel body runs in the longitudinal direction essentially parallel to the outer base, and wherein all the channel bodies have essentially the same overall height between the outer base and the top edge.  
         [0013]     According to a fifth aspect of the present invention, a combination of channel bodies is provided, wherein the top edge of each channel body runs in the longitudinal direction essentially parallel to the outer base, and wherein the combination comprises at least one pedestal which is designed for being attached under at least one of the channel bodies in order to increase its overall height, and wherein the pedestal has a height which is selected in such a way that the overall height of at least one of the channel bodies is essentially equal to the overall height of another of the channel bodies together with the pedestal attached underneath.  
         [0014]     In particular, a drainage channel is provided which has an end on the outlet side and an end remote from the outlet. The channel comprises and defines a conduit for receiving liquid, this conduit being at least partly open at the top. The conduit has a conduit base over which the liquid to be removed collects and over which it flows off. The drainage channel is delimited at the top by a top edge. As a rule, the top edge runs flush with the surface in which the channel is embedded, and therefore preferably runs horizontally. According to the invention, the conduit base is inclined in the longitudinal direction relative to the top edge to a greater degree in a region adjoining the end remote from the outlet than in any other region of the drainage channel. In other words, the gradient of the conduit base at the start of the channel is increased relative to the gradient at the end of the channel. As a result, even relatively small quantities of water, as normally occur at the start of a drainage channel, can be efficiently carried away on account of the increased gradient in this region. This is possible even when, for example, a certain quantity of dirt disturbs the run-off in this region, since said dirt is entrained more easily due to the increased gradient and due to the water pressure increased as a result. At the end on the outlet side, however, only a smaller gradient, or no gradient at all, is required, since the quantities of water transported here become greater as a rule. Due to the correspondingly higher water pressure, these quantities of water will also flow off easily even at a small gradient or if there is no gradient and will entrain any dirt possibly present. Since only a small gradient or no gradient at all need be selected at the end on the outlet side, a greater length of the drainage channel can be achieved at a predetermined installation depth.  
         [0015]     The inclination of the conduit base relative to the top edge preferably decreases monotonically from the end remote from the outlet to the end on the outlet side. In other words, the gradient in the direction of the outlet becomes smaller and smaller over the length of the conduit, i.e. there are no intermediate regions in which the gradient is once again increased relative to the surrounding regions. Since increasingly larger quantities of water are normally transported with decreasing distance from the outlet, it is sufficient that a gradient which becomes smaller and smaller is provided for carrying away said quantities of water in an efficient manner.  
         [0016]     A drainage channel is often composed of individual channel bodies. That channel body which is arranged at the start of the conduit is then of particular interest. This channel body may have a constant inclination of the conduit base relative to the top edge, as a result of which the initial gradient is fixed. According to the invention, the second and all the following channel bodies will then have a smaller inclination of the conduit base (a smaller gradient). However, the gradient preferably already decreases within the first channel body. In other words, the channel body furthest away from the outlet has at the start a region in which the conduit base is inclined to a greater degree than in a region at its end.  
         [0017]     In particular in the region on the outlet side, however, the drainage channel may comprise channel bodies in which the conduit base has no inclination at all in the longitudinal direction relative to the top edge, that is to say it runs parallel to the top edge. Such channel bodies have been known for a long time. They can be used here without any problems, since the flow at the start of the conduit and thus the water pressure are increased. In particular, channel bodies according to the invention may be combined with channel bodies of the prior art which are already within the product range of a manufacturer. In this way, a very cost-effective channel of increased length can be constructed.  
         [0018]     An especially simple construction of the drainage channel is made possible when the outer base with which the channel rests in its bed on the foundation and the top edge of the drainage channel run parallel to one another. Such a drainage channel can be embedded in a trench which has a uniform depth. The requirements for the excavation and for the general preparatory work for such a trench are far less stringent than for a trench which has an inclination, as is required for drainage channels of the prior art. In addition, by virtue of the top edge and the bottom edge running parallel to one another, the channel bodies are given a shape which permits simple stacking and thus simplified storage and transport. The invention accordingly also relates to a channel body whose conduit base is inclined in the longitudinal direction relative to the outer base and whose outer base runs in the longitudinal direction essentially parallel to the top edge.  
         [0019]     In an advantageous configuration, all the channel bodies of the drainage channel or within a group of channel bodies essentially have the same overall height, i.e. the same height between outer base and top edge. In this way, as already described above, the channel bodies can be embedded in a trench which has a uniform depth over its entire length.  
         [0020]     In a further advantageous configuration, pedestals are additionally provided. At that end of the channel which is remote from the outlet, where the conduit has only a small depth, these pedestals enable channel bodies of smaller overall height to be used than at the end on the outlet side, at which the conduit has a greater depth. The channel bodies of smaller overall height are combined with the pedestals in such a way that they have the same total height and thus the same installation depth as the channel bodies of greater overall height, which are preferably used downstream in the direction of flow. In this way, it is again possible for a trench of uniform depth over its entire length to be prepared in a simple manner in order to embed the channel. In addition, the production costs are reduced owing to the fact that some of the relatively expensive channel bodies, which are produced in relatively small quantities and must have relatively high precision, need only be produced with a small overall height. The associated pedestals, however, only require lower precision and can be produced very cost-effectively in large numbers.  
         [0021]     Since the quantity of water will continue to increase in the course of the drainage channel toward the outlet, it is desirable for the conduit to be able to transport a greater quantity of water at its end on the outlet side than at the start. In a region adjoining the end remote from the outlet, the conduit therefore preferably has a cross section which tapers essentially in a V shape toward the bottom. As a result, the water is channeled here in an especially effective manner. On the other hand, in a region adjoining the end on the outlet side, the conduit preferably has a cross section which is essentially U-shaped. The cross section enlarged relative to the V shape enables larger quantities of water to be carried. In addition, the cross section in this region can be adapted if need be to the cross section of channel bodies of the prior art, so that known channel bodies can be used in the region close to the outlet. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]      FIG. 1  is a side schematic view of a drainage channel according to the principles of the present invention;  
         [0023]      FIG. 2A  is a side schematic view of a first channel body according to the principles of the present invention;  
         [0024]      FIG. 2B  is a sectional view of the channel body of  FIG. 2A  in the plane B-B;  
         [0025]      FIG. 2C  is a sectional view of the channel body of  FIG. 2A  in the plane C-C;  
         [0026]      FIG. 3A  is a side schematic view of a second channel body according to the principles of the present invention;  
         [0027]      FIG. 3B  is a sectional view of the channel body of  FIG. 3A  in the plane B′-B′;  
         [0028]      FIG. 3C  is a sectional view of the channel body of  FIG. 3A  in the plane C′-C′;  
         [0029]      FIG. 4A  is a side schematic view of a third channel body according to the principles of the present invention;  
         [0030]      FIG. 4B  is a sectional view of the channel body of  FIG. 4A ;  
         [0031]      FIG. 4C  is a further sectional view of the channel body of  FIG. 4A ;  
         [0032]      FIG. 5A  is a side schematic view of a fourth channel body according to the principles of the present invention;  
         [0033]      FIG. 5B  is a sectional view of the channel body of  FIG. 5A ;  
         [0034]      FIG. 5C  is a further sectional view of the channel body of  FIG. 5A ;  
         [0035]      FIG. 6A  is a side schematic view of a fifth channel body according to the principles of the present invention;  
         [0036]      FIG. 6B  is a sectional view of the channel body of  FIG. 6A ;  
         [0037]      FIG. 6C  is a further sectional view of the channel body of  FIG. 6A ;  
         [0038]      FIG. 7A  is a side schematic view of the sixth channel body according to the principles of the present invention;  
         [0039]      FIG. 7B  is a sectional view of the channel body of  FIG. 7A ;  
         [0040]      FIG. 7C  is a further sectional view of the channel body of  FIG. 7A ;  
         [0041]      FIG. 8A  is a side schematic view of a further embodiment of the third channel body according to the principles of the present invention;  
         [0042]      FIG. 8B  is a sectional view of the channel body of  FIG. 8A ;  
         [0043]      FIG. 8C  is a further sectional view of the channel body of  FIG. 8A ;  
         [0044]      FIG. 9A  is a side schematic view of a further embodiment of the sixth channel body according to the principles of the present invention;  
         [0045]      FIG. 9B  is a sectional view of the channel body of  FIG. 9A ; and  
         [0046]      FIG. 9C  is a further sectional view of the channel body of  FIG. 9A . 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0047]      FIG. 1  illustrates the basic construction of a drainage channel according to the present invention. The highly schematically illustrated drainage channel  1  comprises six channel bodies  20 ,  30 ,  40 ,  50 ,  60  and  70 , pedestals  10  being additionally attached below three of these channel bodies. Each of the channel bodies is defined at the bottom by an outer base  23 ,  33 ,  43 ,  53 ,  63  or  73 , respectively, and lies with this outer base on the foundation (pedestal  10  or directly the bed of the trench). In this case, the outer base is in each case oriented horizontally in the longitudinal direction. At each of the channel bodies, a top edge  22 ,  32 ,  42 ,  52 ,  62  or  72 , respectively, runs in the longitudinal direction parallel to the outer base. This top edge  22 ,  32 ,  42 ,  52 ,  62  or  72 , respectively, defines the respective channel body at the top and runs flush with the horizontal surface (not shown) in which the drainage channel is embedded.  
         [0048]     Each of the channel bodies forms a conduit section for receiving water. Each of the conduit sections in turn has a conduit base  21 ,  31 ,  41 ,  51 ,  61  or  71 , respectively. Each conduit base is inclined in the longitudinal direction relative to the respective outer base and the top edge parallel thereto. In this way, the drainage channel has a gradient, as a result of which water can flow in the direction of an outlet (not shown) at the right-hand end of  FIG. 1 . The inclination of the conduit bases is approximately the same for the second to sixth channel bodies  30 ,  40 ,  50 ,  60  and  70  and is defined by an angle β. On the other hand, the conduit base of the first channel body  20  has an inclination relative to the outer base which changes over the length of the channel body. This inclination is greater at the left-hand end (remote from the outlet) of the channel body  20 , that is to say close to the highest point of the conduit base  21 , than at the right-hand end. The inclination in the region which adjoins the end remote from the outlet is designated as angle a. This angle α is greater than the angle β.  
         [0049]     The first channel body  20  together with its pedestal  10  is shown in more detail in  FIGS. 2A, 2B  and  2 C. This channel body is furthest away from the outlet and forms with its left-hand end the start of the drainage channel, i.e. the point at which the conduit base is at its highest.  FIG. 2A  shows the channel body  20  from the side, and  FIGS. 2B and 2C  show the channel body  20  in cross section in the planes B-B and C-C, respectively. The channel body basically has a Y-shaped cross section which varies continuously over the length of the channel body. In addition, there are reinforcing ribs  24  at regular distances apart, these reinforcing ribs  24  widening the cross-sectional area at the corresponding locations. The underside of the channel body defines the outer base  23 . The channel body is defined at the top by the parallel top edges  22 . The distance between the outer base  23  and the top edge  22  defines the overall height d, of the channel body.  
         [0050]     The channel body defines an essentially V-shaped conduit section which is defined at the bottom by the conduit base  21 . The course of the conduit base  21  is indicated in  FIG. 2A  by a thin line. The height of the conduit base  21  decreases continuously over the outer base  23  from the left-hand end (remote from the outlet) to the right-hand end (close to the outlet). Located between the outer base  23  and the conduit base  21  is a relatively narrow web  25 , the height of which correspondingly decreases continuously.  
         [0051]     The pedestal  10  has essentially the form of an elongated beam which supports the outer base of the channel body  20 . In the same positions as at the channel body  20 , the pedestal  10  also has reinforcing ribs  14  pointing outward. The latter support the reinforcing ribs  24  of the channel body  20  and thereby prevent lateral tilting of the channel body  20 . The pedestal  10  rests with its base surface  13  on the excavated bed of a trench (not shown).  
         [0052]      FIGS. 3A, 3B  and  3 C show the second channel body  30  and  FIGS. 4A, 4B  and  4 C show the third channel body  40  in views similar to  FIGS. 2A, 2B  and  2 C. Reference is accordingly made to the above description in this respect. The cross-sectional planes for the cross-sectional illustrations of  FIGS. 3B and 3C  are the planes B′-B′ and C′-C′, respectively, of  FIG. 3A . The same cross-sectional planes have been selected for the illustrations in  FIGS. 4B and 4C . It can clearly be seen how the conduit base  31  or  41 , respectively, increasingly loses height relative to the outer base  33  or  43 , respectively. At the same time, the cross section of the conduit increasingly widens. The basic cross-sectional shape of the channel body changes more and more from a Y shape to a V shape.  
         [0053]     At the right-hand end of the third conduit section  40 , the conduit base  41  is only at a slight distance from the outer base  43 . The conduit can therefore no longer be continued with the same inclination without increasing the overall height of the channel body to the right of the third channel body  40 .  
         [0054]     The fourth, fifth and sixth channel bodies  50 ,  60  and  70  are shown in  FIGS. 5A, 5B ,  5 C,  6 A,  6 B,  6 C,  7 A,  7 B and  7 C. Concerning the illustrations, reference is again made to the above description with respect to  FIGS. 2A  to  2 C. The cross-sectional planes for the cross sections again correspond to the planes B′-B′ and C′-C′ of  FIG. 3A . These three channel bodies are in principle of a similar type of construction to the first three channel bodies, but have a larger overall height d 2  than the overall height d 1  of the first three channel bodies. As a result, the conduit bases  51 ,  61  and  71 , respectively, can continue to have an inclination relative to the outer bases  53 ,  63  and  73 , respectively, and to the top edges  52 ,  62  and  72 , respectively. The cross-sectional shape of the channel bodies again changes from more of a Y-like cross section at the left-hand end of the channel body  50  to more of a V-shaped cross section at the right-hand end of the channel body  70 , whereas the height of the web between conduit base and outer base decreases.  
         [0055]     The overall height d 2  of the channel bodies  50 ,  60  and  70  corresponds exactly to the common overall height of the channel bodies  20 ,  30  and  40  with their pedestals  10  attached underneath. In this way, the bed on which the channel bodies or pedestals rest can run continuously horizontally over the entire length of the drainage channel without steps being necessary.  
         [0056]      FIGS. 8A, 8B  and  8 C show an alternative embodiment of the third channel body (channel body  40 ′, conduit base  41 ′, top edge  42 ′, outer base  43 ′) shown in  FIGS. 4A  to  4 C. In this embodiment, the cross section of the conduit section defined by the channel body changes from a V-like shape tapering at the bottom in a substantially pointed manner into a U-like shape converging to a round end at the bottom. In this way, the cross section of the conduit is additionally increased, thereby increasing the capacity. Preferably adjoining such a modified channel body are channel bodies similar to the channel bodies shown in  FIGS. 5A  to  7 C, the conduit section of which, however, likewise has a U-shaped cross section. In particular, conventional channel bodies as are often to be found in the prior art can adjoin the third channel body  40 ′ modified in this way.  
         [0057]     In a similar manner,  FIGS. 9A, 9B  and  9 C show an alternative embodiment of the sixth channel body (channel body  70 ′, conduit base  71 ′, top edge  72 ′, outer base  73 ′) shown in  FIGS. 7A  to  7 C. This channel body adjoins the channel bodies  20 ,  30 ,  40 ,  50  and  60  of  FIGS. 2A  to  6 C. The cross section again changes over the length of the channel body from a V shape to a U shape. In this way, connection to further channel bodies of the prior art or to a conventional outlet is possible.  
         [0058]     Instead of the cross section changing from the V shape to the U shape only within a single channel body, this change may also be effected quite gradually over a plurality of channel bodies.  
         [0059]     In the present example, six channel bodies form the drainage channel. If it is desired to construct a longer channel, the channel shown can readily be lengthened. To this end, channel bodies having a third overall height which is greater than the overall height d 2  would adjoin the channel body  70  on the right. In order to be able to install such a drainage channel in a continuously horizontally running trench, further pedestals  10  may be attached under the channel bodies  50 ,  60  and  70  or under the already present pedestals  10  of the channel bodies  20 ,  30  and  40 . Alternatively, the channel may also be extended with channel bodies of the overall height d 2  which have no gradient, i.e. in which the conduit base runs parallel to the top edge and to the outer base, as known from the prior art.  
         [0060]     In the present example, each of the channel bodies has a length of about 1000 millimeters. The overall length of the drainage channel shown is thus 6 meters. The overall height d 1  is 150 millimeters; the overall height d 2  is 195 millimeters. The inclination in the first channel body is graduated in four sections. Over the first 125 mm length, there is an initial inclination α of 9.1°, corresponding to a gradient of 16%. Over the next 125 mm length, the inclination is 4.6° (gradient 8%). Over the following 250 mm length, the inclination is still 2.3° (gradient 4%), whereas it subsequently drops to a value β of 1.1° (gradient 2%). All further channel bodies likewise have an inclination β of 1.1°, that is to say a gradient of 2%. The graduation permits simpler production than a continuous change in the angle of inclination. The percentage specifications relate, as usual, to the ratio of the height difference to horizontally measured distance and correspond to the tangent of the angle of inclination.  
         [0061]     In the case of longer or shorter channels and depending on the field of use, channel bodies of other dimensions and having other angles of inclination of the conduit base may be used. In general, channels which are used in the open and are used for carrying away larger quantities of rain water will more likely have a smaller inclination at a larger length than channels which are used in buildings and are designed for carrying away smaller liquid quantities occurring there. Thus, for example, inclinations of about 0.3° (0.6%) for channels in the open are quite normal. The initial inclination then accordingly does not need to be as large as in the present example. Thus the advantages of the invention can already be achieved even when the angle of inclination α at the start of the channel is increased, for example, by at least about 0.6° (1%), preferably by at least about 1.1° (2%), relative to the angle of inclination β in the region close to the outlet.  
         [0062]     In the present exemplary embodiment, the inclination α at the start of the first channel body is increased eightfold relative to the inclination β. The inclination α in the initial region of the first channel body or in the initial region of the drainage channel is at least about 1.5 times the inclination β, in particular preferably about twice the inclination β, in that region of the drainage channel which is close to the outlet.  
         [0063]     The channel bodies are preferably produced from “polymer concrete”. Polymer concrete (or also polyester concrete) is a mixture of sand, fine gravel and other fillers which is bonded with a polymer component. Polymer concrete has favorable properties for drainage channels. Thus, polymer concrete is in particular water-resistant and watertight and dimensionally stable. However, the invention is in no way restricted to channel bodies of polymer concrete, and the channel bodies may also be made of other materials familiar to the person skilled in the art, such as, for example, normal concrete or plastic.  
         [0064]     In a known manner familiar to the person skilled in the art, the channel bodies are designed for being connected to one another and for accommodating a cover grating at their top end. As examples of such configurations, reference is expressly made to the disclosure of the documents EP-A 0 112 287, EP-A 0 151 684, EP-A 0 399 955, EP-A 0 931 885 and CH-A 690 132.