Abstract:
A fire service elevator includes an elevator cage with a cage roof, wherein the elevator cage is at least partly supported and driven by at least one support device, wherein the elevator cage is looped under by the at least one support device, wherein the elevator cage has a protective element, which is arranged at least partly around the at least one support means and disposed substantially on the cage roof. The protective element screens the at least one support device relative to a central region of the cage roof so that extinguishing water falling onto the cage roof in the case of fire is substantially prevented from wetting the at least one support device.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to European Patent Application No. 11161765.0, filed Apr. 8, 2011, which is incorporated herein by reference. 
     FIELD 
     The present disclosure relates to a fire service elevator. 
     BACKGROUND 
     Modern elevator installations or so-called fire service elevators, which are designed additionally for this purpose, should provide reliable operation even in the case of fire. On the one hand evacuation of persons and/or material, which is at risk, from the stories affected by the fire should be ensured and on the other hand a functionally capable elevator should be available for the transport of fire service personnel and their extinguishing material. In both cases the use of extinguishing water should not have the consequence that the elevator installation or the fire service elevator no longer functions. This applies not only to the use of a sprinkler installation on a story, but also to the use of extinguishing water by the fire service. 
     This means that electric components of the elevator installation should remain dry. Moreover, it should be ensured that a support means is still driven as intended on a drive pulley. Extinguishing water can in that case negatively influence the traction of the support means on the drive pulley. On the one hand, extinguishing water can directly reduce the coefficients of friction between the drive pulley and the support means and on the other hand lubricant present in the extinguishing water can in addition negatively influence the traction between the support means and the drive pulley. A support means wetted by extinguishing water can thus lead to a reduction of traction or even to a complete loss of traction. Particularly in the case of a substantial difference between the weight of the elevator cage and a counterweight an uncontrolled travel of the elevator cage can in that case arise, which has to be stopped by safety brakes. 
     The use of belt-like support means instead of steel cables can have the problem of additionally amplifying the loss of traction between support means and drive pulley. The synthetic material surfaces of belt-like support means sometimes change their traction characteristics in the case of wetting by extinguishing water more strongly than support means of steel cable form. This can make it necessary to conduct away the extinguishing water in controlled manner or to catch it. It can be necessary to prevent traction means sections which co-operate with the drive pulley from being wetted by extinguishing water. 
     The extinguishing water normally penetrates over the shaft doors of the elevator shaft into the elevator shaft. In that case the extinguishing water flows onto a story floor below the shaft doors through into the elevator shaft. 
     SUMMARY 
     Various embodiments disclosed herein comprise a device for protection of the support means from extinguishing water. 
     In at least some embodiments, a fire service elevator with an elevator cage comprises a cage roof, wherein the elevator cage is at least partly supported and driven by at least one support means and wherein the elevator cage is looped under by the at least one support means. The elevator cage comprises at least one protective element, which is arranged at least partly around the at least one support means and disposed substantially on the cage roof. The at least one protective element screens the at least one support means relative to a central region of the cage roof, so that extinguishing water falling onto the cage roof in the case of fire is substantially prevented from wetting the at least one support means. 
     In further embodiments, a drain system is arranged at the outset not at the individual shaft doors, but at the elevator cage itself. This basic concept derives from recognition that the extinguishing water does not necessarily have to be kept away from the elevator shaft, but can also flow away in controlled or deflected manner. It was observed that a common reason of the support means becoming wet is the spraying or atomization of the extinguishing water when impinging on the roof of the elevator cage. 
     In some embodiments, the support means is screened towards at least one further side additionally to the side towards the central region of the cage roof. In further embodiments, the support means is screened towards at least two further sides. 
     In some cases, two protective elements are provided for each support means, namely a respective first protective element substantially over a first side wall of the cage and a second protective element substantially over the second side wall of the cage. Because the extinguishing water drops through slots under the shaft doors into the shaft, in some cases it is important to equip with protective elements those support means which are arranged closer to the shaft doors. 
     In particular embodiments, modifications or, in particular, constructional measures do not have to be undertaken either at the elevator itself or at the elevator shaft. The proposed protective element can, for example, also be retrofitted to existing elevator installations in simple mode and manner. Moreover, this proposed solution can be economic. 
     In further embodiments, elevator cages of different types can be retrofitted. The protective element can be arranged on any of planar, chamfered and even irregularly shaped cage roofs. This can enable retrofitting of the extinguishing water deflecting system to almost all elevator types. The protective element can thus be interpreted as an additional component which can be arranged on existing, intrinsically closed elevator cages. 
     The at least one protective element screens the at least one support means relative to the central region of the cage roof. By central region of the cage roof there is understood a region of the cage roof which is hit by extinguishing water dropping down. Depending on the respective configuration of the elevator this central region can be of different construction with respect to size, position and shape. 
     In some embodiments, the protective element is used in fire service elevators which have support means with a synthetic material casing, such as, for example, belts. The protective element can equally well be used with support means without synthetic material encasing, such as, for example, steel cables, but here the traction loss due to wetting of the support means by extinguishing water is less serious than in the case of support means encased by synthetic material. Such belts usually have a casing of synthetic material arranged around a plurality of tensile carriers disposed parallel to one another. The tensile carriers can be constructed from, for example, steel wires or synthetic fibers. 
     In some embodiments, two protective elements are provided for each support means, wherein with respect to a support means a first protective element is arranged substantially above a first cage side wall and a second protective element is arranged substantially above a second cage side wall. Several support means extending parallel to one another can be arranged, wherein each of these support means loops under the elevator cage. In that case, one or two protective elements can be associated with each support means or even with only those support means which due to an elevator configuration are particularly affected by spraying extinguishing water. 
     So as not to limit travel of the elevator cage in the direction of the shaft head, the protective element is possibly constructed in such a manner that in a use state it does not project above other components of the elevator cage. The height of the protective element is therefore possibly selected so that the protective element does not project above a balustrade. The height of the protective element is, for example, possibly 20 centimeters to 100 centimeters, possibly 30 centimeters to 80 centimeters, possibly 40 centimeters to 60 centimeters. 
     The protective element can be made from various kinds of materials. The protective element possibly consists of an economic, robust and light material which can be shaped or produced by simple methods. An example of such a material is sheet metal. Alternatively thereto, for example, use can also be made of different synthetic materials. The wall thickness of the protective element is, for example, possibly between 0.5 millimeters and 30 millimeters, possibly between 1 millimeter and 10 millimeters, possibly between 1 millimeter and 5 millimeters. 
     The protective element can be substantially arranged on the cage roof of the elevator cage. In that case the protective element can, for example, be fastened on the cage roof itself or to a cage frame. Depending on the respective configuration of the elevator cage, fastening of the protective element can be carried out in different ways. In that case it can be important that the protective element screens the support means, which runs past the elevator cage, relative to a central region of the cage roof. It is also possible, for example, to fasten the protective element to a cage side wall so that the protective element extends above a plane of the cage roof. 
     The protective element can be shaped in various ways. Possible forms are elongate elements with a U-shaped, a V-shaped, an oval, a rectangular or a round cross-section. However, other shapes are also usable. For example, use can also be made of beveled or irregularly shaped elements. It can be important for the selection of the shape that the support means is screened by the protective element at least relative to the central region of the cage roof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure is explained in more detail using the figures, in which: 
         FIG. 1  shows a schematic illustration of an exemplifying elevator installation in a building with a fire extinguishing installation; 
         FIG. 2   a  shows an exemplifying form of embodiment of a protective element; 
         FIG. 2   b  shows an exemplifying form of embodiment of a protective element; 
         FIG. 2   c  shows an exemplifying form of embodiment of a protective element; 
         FIG. 2   d  shows an exemplifying form of embodiment of a protective element; 
         FIG. 3  shows an exemplifying form of embodiment of an elevator cage in plan view; and 
         FIG. 4  shows an exemplifying form of embodiment of an elevator cage with a protective element in three-dimensional illustration. 
     
    
    
     DETAILED DESCRIPTION 
     Fire service elevators can include elevators which have special adaptations so that they can remain capable of use longer in the case of fire. Such adaptations can include, for example, electronic components protected against spray water, fireproof cage elements or a specific control mode for the case of fire. The protective element is similarly such an adaptation. In this sense, any elevator which is equipped with such a protective element is termed a fire service elevator herein. 
       FIG. 1  shows an elevator installation such as is known from the prior art. A cage  1  and a counterweight  2  are arranged in an elevator shaft  10 . In that case, both the elevator cage  1  and the counterweight  2  are coupled with a support device or means  3 . The elevator cage  1  and the counterweight  2  can be vertically moved in the shaft  10  by driving the support means  3  by a drive (not illustrated). In the illustrated exemplifying embodiment not only the elevator cage  1 , but also the counterweight  2  are suspended at support rollers  11 ,  12 . The cage support rollers  11  are in that case arranged below the cage  1  so that the cage  1  is looped under by the support means  3 . By contrast thereto the counterweight support roller  12  is arranged above the counterweight  2  so that the counterweight  2  is suspended at the counterweight support roller  12 . Through the looping-under of the elevator cage  1  the support means  3  is guided along cage side walls  30 . 
     A shaft wall  6  has a respective opening at the height of each story  9 . 1 ,  9 . 2 , which opening can be closed by a respective shaft door  5 . 1 ,  5 . 2 . A fire extinguishing installation  13  is installed on the second-lowermost story  9 . 2 . The fire extinguishing installation  13  is arranged at a ceiling of the story  9 . 2  so that extinguishing water  14  can reach the largest possible number of fire locations. The extinguishing water  14  collects on the story floor  8 . 2  and flows from there, at least partly, through under the shaft door  5 . 2  and into the elevator shaft  10 . As illustrated in  FIG. 1 , the extinguishing water  14  flowing through the shaft door  5 . 2  can drop in the manner of a waterfall from above onto the elevator cage  1 . From the elevator cage  1  the extinguishing water  14  flows further down until it collects at the shaft floor  7  (not illustrated). 
     The distribution of the extinguishing water  14  in the elevator shaft  10  is dependent on, inter alia, the following factors: For entry of the extinguishing water  14  into the elevator shaft  10  the extinguishing water quantity and also a gap size between the shaft door  5 . 2  and the story floor  8 . 2  are at the outset critical. The larger the quantity of extinguished water, the greater the water pressure which can shoot the extinguishing water into the shaft. The shape and size of the gap between the shaft door  5 . 2  and the story floor  8 . 2  have a direct influence on the distribution of the extinguishing water  14  in the elevator shaft  10 . In addition, the distribution of the extinguishing water  14  in the elevator shaft  10  is influenced by the height difference between the elevator cage  1  and the story  9 . 2  from which the extinguishing water  14  penetrates into the shaft  10 . The greater the spacing between a cage roof  15  and the story floor  8 . 2  from which the extinguishing water  14  penetrates into the shaft  10  the more rapidly the extinguishing water  14  falls onto the elevator cage roof  15  and the further the extinguishing water  14  is sprayed from the cage roof  15 . A larger spacing between the cage roof  15  and the story floor  8 . 2  from which the extinguishing water penetrates into the shaft  10  additionally has the consequence that the extinguishing water can propagate more widely and deeply in the shaft  10  due to a higher drop path. 
     The principles and issues described with respect to  FIG. 1  can also occur with different kinds of fire extinguishing installations or different kinds of elevators. 
     Various exemplifying embodiments of a protective element  16  are illustrated in  FIGS. 2   a  to  2   d . The protective element  16  has a height  17 . The height  17  corresponds with the section of the support means  3  which can be screened by the protective element  16 . On the one hand this height  17  is to be as large as possible so as to protect a largest possible section of the support means  3  from spraying extinguishing water. On the other height, this height  17  is not to be so large that a movement of the elevator cage in the direction of a shaft head (not illustrated) is restricted by the protective element  16 . In some embodiments, a height  17  of approximately 50 centimeters can be used. 
       FIG. 2   a  shows an exemplifying protective element  16  with a V-shaped cross-section. This form of embodiment is particularly simple to produce and nevertheless screens the support means from two or three sides depending on how this protective element  16  is arranged. 
       FIG. 2   b  shows an exemplifying protective element  16  with a rectangular cross-section. This protective element  16  can provide that the support means is screened from all sides. However, the support means is introduced through this protective element  16 , which can make subsequent installation of the protective element  16  on an existing elevator cage difficult. 
       FIG. 2   c  shows an exemplifying protective element  16  with U-shaped cross-section. This protective element  16  is, in addition, beveled. This protective element  16  is so arranged on the elevator cage that a maximum height  17  is arranged between the support means to be screened and the central region of the cage roof. In the case of this exemplifying embodiment, elements for fastening the protective element  16  to the elevator cage are in addition illustrated. 
       FIG. 2   d  shows an exemplifying protective element  16  with a U-shaped cross-section. The protective element  16  in this form of embodiment is similar to the protective element in  FIG. 2   a , but the cross-section is U-shaped instead of the V-shaped cross-section in  FIG. 2   a.    
     In all exemplifying forms of embodiment of the protective elements  16  in  FIGS. 2   a  to  2   d , the protective element  16  is so constructed that a support means can be screened by that from at least two sides. Possibly, the protective element  16  is so arranged that the support means is screened from three sides. In at least some embodiments, the support means is screened at least relative to the central region of the cage roof. 
     An exemplifying form of embodiment of an elevator cage is illustrated in plan view in  FIG. 3 . The elevator cage is laterally bounded by the side walls  30 , the back wall  29  and the cage doors  4 . Also illustrated are the support means  3  which are guided through from the cage support rollers  11  below the elevator cage  1 . A central region  18  is illustrated on the cage roof  15 . The support means  3  are screened by support elements  16  towards the central region  18  of the cage roof  15  and towards two further sides. Two protective elements  16  are associated with each support means  3 . 
       FIG. 4  shows an exemplifying form of embodiment of an elevator cage in three-dimensional illustration. Here, too, the elevator cage is looped under by two support means  3 , wherein the support means  3  are guided by support rollers  11  around the elevator cage. Each support means  3  is screened by two support elements  16  towards the central region of the cage roof  15  and towards two further sides. The exemplifying central region  18  in  FIG. 4  differs in size, position and shape from the exemplifying central region in  FIG. 3 . 
     The protective elements  16  in  FIG. 4  are so constructed that they do not project above balustrades  21  arranged on the cage roof  15 . Movement of the elevator cage in the direction of the shaft head (not illustrated) is thereby not additionally restricted by the protective element  16 . 
     Having illustrated and described the principles of the disclosed technologies, it will be apparent to those skilled in the art that the disclosed embodiments can be modified in arrangement and detail without departing from such principles. In view of the many possible embodiments to which the principles of the disclosed technologies can be applied, it should be recognized that the illustrated embodiments are only examples of the technologies and should not be taken as limiting the scope of the invention. Rather, the scope of the invention is defined by the following claims and their equivalents. We therefore claim as our invention all that comes within the scope and spirit of these claims.