Title:
Prefabricated Facade Unit
Kind Code:
A1


Abstract:
The invention relates to a prefabricated facade unit comprising a generally rectangular plate element, e.g. a glass plate, especially a laminated glass plate or insulating glass plate, and profiled elements that are disposed in edge areas of the plate. The profiled elements are configured as pair-wise mating support semi-profiles that project on at least two opposite narrow faces of the plate element from the plate edge areas at a generally right angle to the rear face in the operating position. The semi-profiles are provided with additional profiled channels for accommodating drive means for a wiper-type facade-cleaning element.



Inventors:
Thurnher, Julius (Purkersdorf, AT)
Application Number:
11/794997
Publication Date:
06/19/2008
Filing Date:
01/05/2006
Primary Class:
Other Classes:
15/256.5
International Classes:
E04C2/54; A46B15/00
View Patent Images:



Primary Examiner:
WENDELL, MARK R
Attorney, Agent or Firm:
COLLARD & ROE, P.C. (ROSLYN, NY, US)
Claims:
1. A prefabricated facade unit (2) including a generally rectangular plate part (16) and profile elements mounted in edge regions of the same, wherein said profile elements on at least two opposite narrow sides (17) of the plate part (16) are designed as carrier semi-profiles (18, 19; 34, 35) pairwisely fitting into each other and projecting from the plate-part edge regions in a generally rectangular manner relative to the rear side, viewed in the operating position, which include additional profile channels (27, 28) for accommodating drive means (29) for a wiper-like facade cleaning element (7).

2. A facade unit according to claim 1, wherein carrier semi-profiles (18, 19; 34, 35) pairwisely fitting into each other are provided on all four sides of the plate part (16), with only one pair of carrier semi-profiles (18, 19) being formed with profile channels (27, 28) for accommodating drive means (29).

3. A facade unit according to claim 2, wherein those carrier semi-profiles (18, 19) which are provided on the vertical sides, viewed in the operating position, are formed with profile channels (27, 28).

4. A facade unit according to claim 1, wherein the carrier semi-profiles (18, 19; 34, 35) fitting into each other comprise profile legs (40-43) provided for engagement under mutual abutment, wherein at least one of the respective profile legs (23, 24) intended for mutual abutment carries a seal (25, 26) for the tight abutment on the associated profile leg (21, 22) of an adjacent facade unit (2).

5. A facade unit according to claim 1, wherein two profile channels (27, 28) are each provided for accommodating a run (30, 31) of a continuous drive means (29).

6. A facade unit according to claim 5, wherein the continuous drive means (29) is a toothed belt (32).

7. A facade unit according to claim 1, wherein the profile channel, or one (27) of the two profile channels (27, 28) of the respective carrier semi-profile (18, 19), comprises a lateral opening (62′) for the passage of a carrier part (62) for the facade cleaning element (7).

8. A facade unit according to claim 1, wherein the profile channel (27), or one of the two profile channels of the respective carrier semi-profile (18, 19), forms a guide channel (64) for at least one roller or slide element (63) of the drive means (29).

9. A facade unit according to claim 8, wherein one of the carrier semi-profiles (18, 19) including the guide channel (64) comprises bridging pieces (89) inserted in the profile channel (27) and reaching into a joint (5) present in the operating position to the adjacent facade unit (2).

10. A facade unit according to claim 9, wherein said bridging pieces (89) are made of a synthetic material.

11. A facade unit according to claim 1, wherein one (19) of the two carrier semi-profiles (18, 19) comprising the additional profile channels carries a center rail (80) in the region of the profile channel(s), which center rail extends in the region of the narrow side (17) of the plate part (16).

12. A facade unit according to claim 11, wherein the center rail (80), on one of its ends, carries a joint bridging element (87) for connection to a center rail (80′) of an adjacent facade unit.

13. A facade unit according to claim 11 wherein the ledge-shaped center rail (80), on its two longitudinal sides, carries seals (81) for abutment on the carrier parts or on cleaning element supports (61) connected with the neighboring carrier parts in the operating position.

14. A facade unit according to claim 11, wherein the center rail (80) is T-shaped in cross section and engages with its transverse web (84) in a profile groove (86) provided in the region of the or a profile channel (28).

15. A facade unit according to claim 14, wherein said transverse web (84) engages in the profile groove (86) via an interposed seal (85).

16. A facade unit according to claim 1, wherein the carrier semi-profiles (18, 19; 34, 35) in the edge regions adjacent the narrow sides (17) of the plate part (16) are connected with the latter by an adhesive (33).

17. A facade unit according to claim 1, wherein the carrier semi-profiles (18, 19), which are vertical in the operating position, are equipped with protruding connection parts (47) for the preferably adjustable fixation to building-fixed supports (46).

18. A facade unit according to claim 17, wherein the connection parts (47) are hook-shaped.

19. A facade unit according to claim 17 wherein the connection parts (47) include adjustment screws (57) for the fine adjustment of the height of the facade unit (2) relative to the building-fixed supports (46).

20. A facade unit according to claim 1, wherein the plate part (16) is a glass plate.

21. A facade unit according to claim 1, wherein the plate part (16) is a laminated glass plate.

22. A facade unit according to claim 1, wherein the plate part (16) is an insulating glass pane.

23. A carrier semi-profile (18, 19; 34, 35) for a facade unit according to claim 1.

24. A facade comprising facade units according to claim 1.

Description:

The invention relates to a prefabricated facade unit including a generally rectangular plate part, e.g. a glass plate, preferably a laminated glass plate or an insulating glass pane, and profile elements mounted in edge regions of the same.

It is known to use such prefabricated facade units, in particular those including insulating glass panes, for external wall glazings or glass facades, cf., for instance, EP 599 264 A. The known facade units when being mounting are fastened to supporting structures such as support profiles by the aid of holding profiles fastened to the plate parts, optionally in connection with wooden posts. Mounting is, thus, relatively labor- and time-intensive, also requiring extensive adjustment operations in order to finally obtain a facade comprising uniform, aligned facade units.

From WO 01/43614 A it is known to provide an automatic cleaning device for such facades; to this end, special vertical guide rail units are installed, which are fastened to profiles interconnecting the glass surfaces, i.e. facade units, and comprise vertical guide channels for carriers connected with wiper strip units. In the vertical guide channels are provided continuous drive elements, i.e. toothed belts, with which the carriers for the wiper strip units are firmly connected. Also there, the mounting of the facade units and the facade cleaning device, in the main, is relatively elaborate and cumbersome.

It is now an object of the invention to take remedial action and provide a prefabricated facade unit of the initially defined kind, which enables simple, quick and precise mounting to buildings and which, in particular, is to already include also essential parts for the installation of a facade cleaning device. The invention also aims to largely equip the individual facade units already during their production in manufacturing plants with the required mounting means and means for accommodating the desired facade cleaning device, such a pre-equipment of the facade units in manufacturing plants being feasible in a simpler and more precise manner than by subsequent mounting on the construction site.

To solve this object, the invention provides a prefabricated facade unit having the features of claim 1; advantageous embodiments and further developments are the subject matters of the dependent claims.

By the configuration according to the invention, the aforementioned objective is met in an advantageous manner, while enabling an extremely simple, quick, unproblematic mounting of the prefabricated facade units on a building as well as a simple and quick mounting of the elements that are essential for the final installation of the facade cleaning device. By the plate parts, i.e., in particular, laminated glass plates or insulating glass plates, being pre-equipped with carrier semi-profiles on at least two opposite narrow sides and, preferably, on all four narrow sides, it is possible on the construction site to simply arrange the individual facade units side by side and/or one above the other, whereby the semi-profiles will then engage with each other to complete the vertical and/or horizontal carrier profiles to a box-like form. Furthermore, the vertical semi-profiles, in particular, are already pair-wisely equipped with additional profile channels, which serve to accommodate drive means for wiper-like facade cleaning elements. These drive means are preferably designed as continuous drive means, e.g. toothed belts, yet optionally also as chains, ropes or the like, as is known per se from WO 01/43614 A, and carrier parts for the respective facade cleaning elements are firmly connected, likewise in a manner known per se, with these drive means, which are subsequently introduced into the additional profile channels. To this end, it is provided according to a preferred embodiment that the profile channel, or one of the two profile channels of the respective carrier semi-profile, comprises a lateral opening for the passage of a carrier part for the facade cleaning element.

It should be noted that it will, of course, do to form just one pair of carrier semi-profiles with such drive means profile channels like, preferably, the semi-profiles which are vertical in the operating or mounted position, in the event that a facade cleaning device configuration comprising facade cleaning elements (wiper strips) to be movable up and down is to be provided. In this respect, a configuration comprising horizontally movable cleaning elements would also be conceivable, wherein the horizontal semi-profiles would then have to be formed with profile channels for the drive means.

In order to prevent the penetration of moisture, dirt or the like in the region of the completed support profiles, it is advantageous if the carrier semi-profiles fitting into each other comprise profile legs for engagement under mutual abutment, wherein at least one of the respective profile legs intended for mutual abutment each carries a seal for the tight abutment on the associated profile leg of an adjacent facade unit. Such seals, moreover, also enable the attainment of a tight closure of the carrier semi-profiles even in the event of unavoidable manufacturing tolerances, wherein, with a suitable fixation of the prefabricated facade units to the building by simple suspension and telescoping, no further connection of the telescoped carrier semi-profiles will, by the way, be required, as will be explained in more detail below. But where the plate parts are framed by carrier semi-profiles, it is, however, suitable to respectively connect these semi-profiles in the corner regions, for instance by the aid of screws, in order to obtain a rigid profile frame structure on the plate parts.

In order to ensure the smooth, unproblematic movement of the facade cleaning elements, it will also be advantageous if the profile channel, or one of the two profile channels of the respective carrier semi-profile, forms a guide channel for at least one roller or slide element of the drive means. These roller or slide elements are, in particular, provided in the region of the carrier parts so as to ensure a precise, linear movement of the carrier parts plus cleaning elements such that the cleaning elements, i.e. wiper strips, are constantly guided in uniform abutment on the outer surfaces of the facade units, in particular on the outer surfaces of the glass plates, without involving undesired temporary lifting or “rumbling”.

In order to ensure a smooth movement of the cleaning elements even over transition regions between individual facade units where joints may be present, it will also be beneficial if one of the carrier semi-profiles including the guide channel comprises bridging pieces preferably made of synthetic material, which are inserted in the profile channel and reach into a joint present in the operating position to the adjacent facade unit. These bridging pieces, by a plug-in part, each project into the respective semi-profile, or its profile channel adjacent the guide channel to be more precise, said plug-in part being firmly connected (in one piece) with a guide portion extending the guide surface of the guide channel within the joint. The height or length of the guide portion corresponds to the width of the joint. Furthermore, the plug-in part of the bridging piece may be so long as to reach into the one facade unit into which it is preinserted, and be able to be also plugged into the respectively adjacent facade unit on its opposite side during mounting. The bridging pieces may be made of synthetic materials in the form of injection-molded parts, exemplary materials including polyamide (nylon), ABS etc.

For an optionally tight guidance of the carrier parts for the cleaning elements (supports) between adjacent plate parts (insulating glass plates or the like), it is of particular advantage if one of the two carrier semi-profiles comprising the additional profile channels carries a center rail in the region of the profile channel(s), which center rail extends in the region of the narrow side of the plate part. Such center rails may be provided with seals to enable the tight abutment of the carrier members or cleaning element supports on them. These seals may optionally also be located opposite corresponding seals provided on the semi-profiles, said seals, for instance in the form of lip seals, directly abutting on each other in the region outside the carrier members or cleaning element supports and being forced apart during the passage of the carrier parts.

In order to prevent possible joints present between adjacent facade units from becoming undesired points of impact in the mounted, operating position, it is beneficial if the center rail, on one of its ends, carries a joint bridging element for connection to a center rail of an adjacent facade unit. Like the previously mentioned guide bridging pieces, these joint bridging elements too may each be pre-mounted to the already prefabricated facade unit, the only thing required during the mounting of the facade unit being the connection to the respectively adjacent facade unit—by appropriate adjoining or slipping in or slipping on. For such pre-mounting, it is also advantageous in terms of center rails, if the center rail is T-shaped in cross section and engages with its transverse web in a profile groove in the region of the or a profile channel, preferably via an interposed seal.

The carrier semi-profiles, in the edge regions adjacent the narrow sides of the plate part, may be connected with the latter by simple adhesion. It is, of course, also conceivable to provide bordering or clamping profile sections, which may be formed in one piece with the semi-profiles and clampingly seize or encompass the narrow sides of the plate parts, in particular glass plates.

For the simple mounting of the prefabricated facade units to the building by simple suspension, it is finally particularly advantageous if the carrier semi-profiles, which are vertical in the operating position, are equipped with protruding connection parts for the preferably adjustable fixation to building-fixed supports. The connection parts are preferably hook-shaped, being slipped on the respective building-fixed support with the hook opening oriented downwards. In the region of these connection parts and, in particular, hook-shaped connection parts, adjustment screws provided on bridging portions of the connection parts and vertical in the mounting position may be provided for the fine adjustment of the height of the facade unit relative to the building-fixed supports. These connection parts too may be readily pre-mounted already at the manufacturing plant such that the assembly of the facade units on the construction site can actually be limited to the mere slipping into each other, or slipping onto the building-fixed supports particularly by way of suspension.

The subject matter of the invention also comprises the carrier semi-profiles provided for the present facade unit as well as, furthermore, a facade constructed by the present facade units.

In the following, the invention will be explained in more detail by way of particularly preferred exemplary embodiments, to which it is, however, not to be restricted, and with reference to the drawing. In the drawing, in detail:

FIG. 1 is a schematic view of a building facade comprising facade units to be cleaned, which are formed, in particular, with glass plates, wherein a vertically displaceable wiper strip unit is provided as a cleaning device for each vertical row of facade units;

FIG. 2 depicts a horizontal cross section in the connection region between two facade units, along line II-II of FIG. 1;

FIG. 3 depicts the respective horizontal section through a prefabricated facade unit, without adjacent facade units, yet already in a position mounted to the building by suspension;

FIG. 4 depicts a vertical section through a facade unit in the operating position suspended from the building, yet without adjacent facade units;

FIG. 5 depicts a vertical section in the region of a horizontal connection site between two adjacent, superimposed facade units in the mounted state, from which the formation of a horizontal support by the adjacent, mutually telescoped carrier semi-profiles is apparent;

FIG. 6, in a schematic side view, illustrates the components that are essential for the fixation of the facade units on the building by suspension in a support;

FIGS. 7 and 7A are each an elevational illustration of a joint bridging element in the region of center rails between adjacent facade units one above the other;

FIG. 8 schematically illustrates a joint bridging piece having guide portions extending guide surfaces in guide channels of the semi-profiles in joints between adjacent facade units one above the other, to guide rollers or sliding blocks for carrying facade cleaning elements in an impact-free manner over the joints; and

FIG. 9 is a schematic illustration of a carrier part of the drive means for the facade cleaning elements, including a plurality of rollers enabling the frictionless passage of joints between adjacent facade units without transition piece by the respective application of at least three rollers of the group on opposite guide surfaces of the guide channel.

FIG. 1 is a completely schematic view of a building 1 with facade units 2 to be cleaned being provided on a facade surface 3. The facade units 2 are, for instance, separated from one another by vertical joints 4 and horizontal joints 5, wherein facade cleaning devices 6 including wiper strips 7 are displaceable up and down via said vertical joints 4, as will be explained in detail below. Similarly as described in WO 01/43614 A, each of the wiper strips 7 is vertically displaceable along a vertical row of facade units 2 in the sense of double arrow 8, to which end continuous drive means, particularly in the form of toothed belts are provided, which are placed in the region of the vertical narrow sides of the facade units 2 without being illustrated in detail in FIG. 1; each of these drive means is slung over toothed wheels 9 and 10 respectively provided on the upper and lower sides of the facade surface 3, said toothed wheels 9, 10 each mounted on a common shaft so as to rotate together; it is at least provided that, for instance, the upper toothed wheels 9 sit on a common drive shaft 11, which is only very schematically indicated in FIG. 1 by broken lines. This drive shaft 11 is driven by a stationarily arranged motor 12, which is likewise illustrated only very schematically.

Furthermore, FIG. 1 depicts a main feed line 13 including a shutoff valve 14 for supplying a cleaning fluid to spraying nozzles 15 provided in the region of the facade units 2. These spraying nozzles 15 may have nozzle cross sections or distances varying over the height of the building 1 in order to compensate for pressure drops occurring over the height of the facade surface 3. As will be explained below by way of FIG. 4, the spraying nozzles 15 may also be accommodated in a horizontal region within the individual facade units 2.

Water, optionally supplemented with a detergent, is, in particular, used as said cleaning fluid.

FIG. 2 in a horizontal section illustrates the connection region between two horizontally adjacent facade units 2A, 2B, each facade unit 2 (or 2A, 2B, respectively) comprising a plate part 16. This plate part 16 in a conventional manner is comprised of a laminated glass plate (insulating glass) and, in the following, is simply referred to as glass plate 16. Each glass plate 16, on its rear side viewed in the mounted, operating position, i.e. on its side facing the building 1, comprises, in the edge region adjacent the vertical narrow side 17 (cf. FIG. 3), a vertical carrier semi-profile 18 and 19, respectively, which, together, form a box-shaped, closed support profile (section) 20. The two semi-profiles 18, 19, which are designed to match each other, engage each other by profile legs 21, 22, on the one hand, and 23, 24, on the other hand, i.e. the profile legs 21, 23 and 22, 24, respectively, abut each other in pairs, particularly via an interposed seal 25, 26, respectively, in a profile groove of one of the semi-profiles 19. No further, in particular, mechanical and/or force-locking connection is provided between the semi-profiles 18, 19.

The semi-profiles 18, 19 are each formed with profile channels 27, 28 for receiving drive means 29, said drive means 29 in the exemplary embodiment illustrated being designed as continuous drive means 29 having a front run 30 in the front profile channel 27 and a rear run 31 in the rear profile channel 28. The continuous drive means 29 are preferably provided in the form of toothed belts 32 to enable slack-free driving.

Each of the semi-profiles 18 and 19 is fastened to its associated plate part 16 on the rear side in a conventional manner by the aid of an adhesive mass 33. If desired, the semi-profiles 18, 19 may also comprise profile legs clampingly grasping or encompassing the plate parts 16, which profile legs are not illustrated in detail in the drawing.

Each of the vertical semi-profiles 18, 19, for each of the facade units 2 or 2A, 2B, is firmly connected with a horizontal carrier semi-profile 34, 35, respectively (cf. FIGS. 4 and 5 in addition to FIGS. 2 and 3). This connection may, for instance, be realized by the aid of screws 36, 37 and 38, which are screwed from the respective vertical semi-profile, e.g. 19 in FIG. 2, into the associated horizontal semi-profile, e.g. 35. To this end, suitable screw seats 39 may be formed in the respective semi-profile, cf., in particular, at the bottom of FIG. 4. Each of the facade units 2, on its rear side facing the building 1, thus, comprises a rectangular profile frame comprising profile elements open to all four sides to enable the connection to other facade units as described, i.e. by pushing said profile elements into each other. As is apparent from FIG. 5 in the region of a horizontal joint 5 (cf. FIG. 1), also the horizontal carrier semi-profiles 34, 35 are, in fact, inserted into each other during mounting by the aid of profile legs 40, 41 and 42, 43, respectively, via interposed seals 44, in a manner analogous to the vertical profiles 18, 19.

Optionally, a stiffening profile 45′, which is entered in broken lines in FIGS. 4 and 5, may each be attached to the respective upper semi-profile 34 of a facade unit 2 to thereby ensure a particularly rigid horizontal support structure 45 (cf. FIG. 4). This stiffening profile 45′ is T-shaped in cross section and, in its vertical leg 45″, may include openings, which are not illustrated in detail in the drawing, to enable crane hooks to be hooked in, or a crane rope to be attached, in order to lift the respective prefabricated facade unit 2 during mounting on the building 1.

The thus formed, prefabricated facade units or elements 2 are mounted to the building 1 (still without continuous drive means 29), wherein, during mounting, the respective semi-profiles of adjacent facade units 2 are simply pushed into each other—as pointed out above. In addition, the individual facade units are also suspended on building-fixed supports 46 (cf. FIGS. 2, 4 and 5 as well as, in particular, FIG. 6) by their upper edge regions using hook-shaped connection parts 47. These hook-shaped connection parts 47 by the aid of screws 48 are screwed to the respective rear legs 21 and 23 of the respective semi-profile 18 and 19, respectively, on the upper edges thereof, reinforcement rails 49, 50—the latter having threaded bores for screwing in screws 48—being provided on both sides of the profile legs 21 and 23.

The support 46, in turn, is fixed in a ceiling 51 by the aid of a U-profile rail 52 having bent upper flange rims 53, and by the aid of screws 54, said screws 54 allowing for the adaptation of the support 46 relative to the ceiling 51 in terms of height during mounting. After mounting, a common floor fill, coating or flooring 55 is applied to the ceiling 51, cf., e.g., FIGS. 4 and 5. The rail 52 is concreted into the ceiling 51.

The support 46 is upwardly angled on its free front end 56, cf., in particular, FIG. 6, in order to form a seating for an adjustment screw 57 on the connection part 47. The adjustment screw 57 can be passed through a bridge part 58 of the connection part 47.

After having mounted the facade units 2, the above-mentioned wiper strip units 7, along with the associated continuous drive means 29 and the associated carrier parts 60 as well as supporting parts 61, are mounted per vertical row of facade units 2 as cleaning elements for the present facade 3, cf. FIG. 2. The carrier parts 60, as is principally known from WO 01/43614 A, are comprised of two block parts which are screwed to each other with the toothed belt 32 interposed, and which are connected with the plate-shaped, angled supporting parts 61 for the wiper strip units 7 via an internal block part 62, at least one roller element 63 being also rotationally mounted in said connection region. Theoretically, such a roller 63 may also be replaced with a slide element made of a low-friction synthetic. This roller or slide element 63 is arranged in a guide channel 64 of the front profile channel 27 so as to ensure a uniform movement of the carrier part 60 along the profile channel 27 during the upward and downward movements of the wiper strip units 7.

As is apparent from the schematic side view of FIG. 9, several, e.g. five, rollers 63 may also be journalled on the block part 62 one above the other, with their axes of rotation slightly offset relative to one another in the horizontal direction, in order to alternately ensure an abutment of the whole carrier 60 alternately on one side and on the other side of the guide channel 64. This will also safeguard the smooth passage of a joint region (indicated in broken lines in FIG. 9), since several rollers 63 will always each abut on both sides thereof in a guide channel 64, thus preventing tilting in the region of the joint 5.

As is, moreover, apparent from FIG. 9 and from FIG. 2, each of the wiper strip units 7 comprises a wiper strip 70, which projects out of a housing 71 and lies against the outer glass surface of the insulating glass 16 of the facade unit 2. The housing 71 is screwed with the cleaning element support 61, as is apparent from FIG. 2 at 72. The wiper strip 70 may be fixed in a separate profile holder 73, cf. FIG. 9, which is, in turn, retained in the housing 71, optionally in a horizontally displaceable manner. Furthermore, a roller 74 is rotationally mounted on either side of the wiper strip housing 71, which rollers 74 may optionally come to abut on joint profile covers 75 and 75′, respectively, so as to subsequently also be able to optionally cause the insertion of the profile holder 73 into the housing 71 via a connection of the roller shaft 76 (FIG. 9) with the wiper strip holder 73 during the backward movement of the rollers 74. Joint covers of various types are illustrated in FIG. 4 at 75 and 75′ and 75″, respectively, wherein it is apparent from FIG. 4 that the plate part 16 of the facade unit 2 may optionally also be subdivided by horizontal joints and separation profiles, e.g. 77, 78, in a conventional manner. The previously explained frame-like arrangement of the semi-profiles 18, 19, 34, 35 nevertheless provides a uniform facade unit 2.

From FIG. 4, it is further apparent that at one of these separation profiles, e.g. 77, spraying nozzles 15′ may likewise be provided in the region of the respective joint cover 75′. The connection of the spraying nozzles 15 (FIG. 1) and 15′ (FIG. 4) to the detergent line 13, in a manner conventional per se, may, for instance, be realized via hose ducts or tubes such that any further description of the same will be omitted.

From FIG. 2, a center rail 80 is further apparent, which is arranged in the region between two respectively adjacent facade units 2A, 2B and effects the sealing of the vertical joint 4 in the region between the semi-profiles 18, 19 via seals 81 which cooperate with seals 82 provided on the semi-profiles 18, 19; in doing so, the seals 81, 82 also provide the sealing and guidance of the respective wiper strip support 61, as the latter is moved up and down along the vertical narrow sides of the facade units 2 and between the seals 81, 82. The center rail 80 is closed on its front side by an inwardly toothed U-profile 83 and is substantially T-shaped in cross section, as is apparent from FIG. 2, its rear web 84 being retained in special profile grooves 86 via interposed seals 85. In a suitable manner, such a center rail 80 is each already prefixed to a vertical side of a prefabricated facade unit 2 as indicated in FIG. 3 prior to and during mounting. In respect to FIG. 3, it should also be noted that the prefabricated facade unit 2 per se does not carry a wiper strip unit 7, yet this has already been illustrated in FIG. 3 to elucidate the mutual assignment, along with the drive means 29.

From FIG. 7 it is apparent that the U-profile 83 attached in the front may, for instance, project upwardly from a center rail 80 of a lower facade unit, which is just indicated by 2 and not illustrated in detail in FIG. 7, and, during mounting, is connected with the center rail 80′ of the facade unit 2′ then mounted thereabove, in order to thereby ensure the precise orientation of the center rails 80, 80′ in the vertical direction despite the distance in the joint region 5. In order to enable this, the center rail 80′ of the above-mounted facade unit 2′ has a U-profile 83′ beginning with the lower end in an offset manner. From FIG. 7, the inwardly arranged web portions 84 are further apparent.

As an alternative to the protruding U-profile 83 according to FIG. 7, a joint bridging element 87 that is H-shaped in a vertical section may also be prefixed on one of the prefabricated facade units, e.g. the upper facade unit, to the center rail 80′ of the same, said bridging element 87, during mounting, by its lower opening 88 being slipped on, and fastened to, a narrower portion of the subjacent center rail 80 of the facade unit arranged therebelow, which portion is, for instance, chamfered or rounded on its upper side.

FIG. 8 is an elevational view of a joint bridging piece 89 for extending guide surfaces within the guide channels 64 of the semi-profiles 18 and 19, respectively, between vertically superimposed facade units. The joint bridging piece 89 guides the roller elements 63 or slide pieces for carrying along the facade cleaning elements over the horizontal joints 5 in an impact-free manner. For the attachment of the bridging piece 89, projecting brackets 90 are provided, which are simply inserted into the respective profile channel 27 of at least one semi-profile 18. The joint bridging piece 89 will, thus, snugly sit in at least one of the adjacently arranged semi-profiles 18 so as to be secured against slipping.

As already mentioned, it is proceeded, during mounting of the described facade units 2, in a manner that the latter, after having been prefabricated with the semi-profiles 18, 19, 34, 35 attached to the plate parts or glass plates 16 and preferably made of aluminum, optionally together with premounted center rails 80, U-profiles 83 and/or joint bridging elements 87 etc., are attached to a facade 3 one after the other and one above the other, wherein a row of semi-profiles similar to the semi-profiles 35 may be attached to the bottom of the facade 3 in order to enable the lowermost row of facade units 2 to be attached first. After having mounted the facade units 2, the drive means 29 with the carrier parts 60 and cleaning element supports 61 are mounted in the profile channels 27, 28, followed by the fixation of the wiper strip units 7.

The horizontal joints 5 may, of course, only be provided in the region of the superimposed plate parts 16 and vertical semi-profiles 18, 19, but not at the horizontal semi-profiles 34, 35, which are stuck into each other during mounting. In this connection, it would be conceivable to allow the plate parts 16 to directly abut each other like the vertical semi-profiles 18, 19, as the facade units 2 are mounted one above the other, yet the provision of joints 5 or distances may be desired or required for aesthetic reasons as well as in view of possible manufacturing tolerances, for instance to prevent the abutting vertical semi-profiles 18, 19 from impeding the proper mounting of one facade unit 2 above the other while joining the respective horizontal semi-profiles 34, 35 in the case of possible overlengths.

The heights of the facade units 2, as a rule, are a function of the height of the stories of the respective building 1, since the suspension of the facade units 2 in the supports 46 embedded in the story ceilings will, thus, be enabled without requiring the attachment of supports on any other sites.