You are an expert at summarizing long articles. Proceed to summarize the following text:

You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION 
     1. Field of the Invention. 
     The present invention relates to collapsible housing, and more particularly, to a retractable cover with telescopically extending portions movable over rails or wheels to house predetermined areas and spaces to protect them. 
     2. Description of the Related Art. 
     Applicant believes that the closest reference corresponds to U.S. Pat. No. 3,415,260 issued to Hall in 1968 for an Extensible Canopy Structure. However, it differs from the present invention because the present invention has retractable portions with telescopically extending rigid portions. The canopy in the patented structure does not provide the same degree of protection as in the present invention. Furthermore, to implement Hall&#39;s patent, as shown in FIG. 2, the canopy has to be made out of a very thin material. Otherwise, a very bulky body would develop, or else, it would have to be removed. The present invention provides a volumetric solution. 
     Other patents describing the closest subject matter provide for a number of more or less complicated features that fail to solve the problem in an efficient and economical way. None of these patents suggest the novel features of the present invention. 
     SUMMARY OF THE INVENTION 
     It is one of the main objects of the present invention to provide a telescopically extending cover structure that is easily movable to house predetermined areas and spaces to protect them and the objects within them such as vehicles, pools, and other objects and structures. 
     It is another object of this invention to provide a telescopic system with portions that engage and interlock with cooperative seals resulting in a water tight structure. 
     It is yet another object of this invention to provide such a device that is inexpensive to manufacture and maintain while retaining its effectiveness. 
     Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     With the above and other related objects in view, the invention consists in the details of construction and combination of parts as will be more fully understood from the following description, when read in conjunction with the accompanying drawings in which: 
     FIG. 1 represents an isometric view of the present invention in the retracted position. 
     FIG. 2 shows an isometric view of the present invention in the extended position. 
     FIG. 3 is a representation of a cross sectional view of an end of one of the portions taken along line  3 — 3  in FIG. 2 showing the wheel and rail assembly. 
     FIG. 4 illustrates a cross sectional top view of the invention taken along line  4 — 4  in FIG. 2 showing the engagement and adjoining partitions. 
     FIG. 5 is a broken detail isometric view of the stopper tabs and cavities receiving the tabs on the longitudinal walls opposite to those shown in FIG.  4 . 
     FIG. 6 represents a detailed view of the stopper tabs taken from circle  6  in FIG.  4 . 
     FIG. 7 shows an isometric view of another embodiment represented in FIG. 6 for the present invention in the extended position. 
     FIG. 8 represents an isometric view of another embodiment for the present invention in the retracted position. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings, where the present invention is generally referred to with numeral  10 , it can be observed that it basically includes stationary portion  30 , telescopic portions  40 ;  50  and  60 , and guiding assemblies  70 ;  80 ;  90 ;  70 ′;  80 ′ and  90 ′. Portions  30 ;  40 ;  50  and  60  include, side walls  36 ;  36 ′;  46 ;  46 ′;  56 ;  56 ′;  66  and  66 ′ respectively, that are parallel and spaced apart relationship to each other. The side walls are perpendicularly mounted to top walls  36 ″;  46 ′″;  56 ″ and  66 ″. 
     As seen in FIG. 1, stationary portion  30  is anchored in place at a predetermined location. Portion  30  is shaped in such a way that it receives telescopic portions  40 ;  50  and  60  in the retracted position. Portion  30  is slightly larger in size with just enough internal clearance to allow telescopic portion  40  to fit within the former, and telescopic portion  40 , similarly, is slightly larger in size than portion  50  and portion  50  is larger than portion  60  so that the former portions receive the latter portions when retracted. Portions  30 ;  40 ;  50  and  60  each include two spaced apart and parallel side walls  36 ;  46 ;  56  and  66  and top walls joining them. In the preferred embodiment, guiding assemblies  70 ;  80 ;  90 ;  70 ′;  80 ′ and  90 ′ can be implemented with channels on surface S. Guiding assemblies  70 ;  80 ;  90 ;  70 ′;  80 ′ and  90 ′ are of sufficient length to allow telescopic portions  40 ;  50  and  60  to fully travel predetermined distances. 
     A seen in FIG. 2, telescopic portions  40 ;  50  and  60  are fully extended. Telescopic portion  40  is movable over guiding assemblies  70 , and  70 ′. Telescopic portion  50  is movable over guiding assemblies  80  and  80 ′. Guiding assemblies  80  and  80 ′ extend a distance equal to the length of assemblies  70  and  70 ′ plus the length of portion  50 . In the same manner, guiding assemblies  90  and  90 ′ extend a distance equal to the length of assemblies  80  and  80 ′ plus the length of portion  60 . Guiding assemblies  70 ;  80  and  90  (and  70 ′;  80 ′ and  90 ′) are disposed in parallel and spaced apart relationship with respect to each other and extend a predetermined distance within portion  30  that is at least the length of portions  40 ;  50  and  60 . In one of the applications, like the one shown in FIGS. 1 and 2, the present invention has cooperative dimensions to house a vehicle and protect it from the natural elements, such as sunlight, rain, wind, and hail. 
     FIG. 3 illustrates one of the preferred embodiments for guiding assemblies  90  and  90 ′ (which can also be used for assemblies  80  and  80 ′;  70  and  70 ′). Channel  92  includes a substantially flat bottom surface  93  supporting longitudinally extending I-beam  94  with upper and lower flanges  94 ′ and  94 ″ at a spaced apart and parallel relationship with respect to each other. The lowermost end of portion  60  includes longitudinally extending cavity  62  with opposite surfaces kept at a spaced apart and parallel relationship with respect to each other. Wheels  86  and  86 ′ are rotatably mounted to walls  65  and  65 ′. Wheels  86  and  86 ′ ride over flange  94 ″ and their vertical movement is limited by upper flange  94 ′. In this manner, telescopic portion  60 , for instance, can be readily moved along guiding assembly  90 . 
     As best seen in FIG. 4, a partial cross-section of retractable cover  10  is shown in the expanded or extended position. Stationary portion  30  is anchored to a fixed location, typically against a stationary wall W. Front end wall  32 , perpendicularly mounted to wall  36 , serves to stop telescopic portion  40  at a predetermined distance when the latter is expanding by making contact with rear end wall  44 , which is perpendicularly mounted to wall  46 . Also, perpendicularly mounted to wall  46  is front end wall  42 . Front end wall  42  extends outwardly defining tab  48  and inwardly with end wall section  49 . Tab  48  serves to stop telescopic portion  40  at a predetermined distance by making contact with front end wall  32  in the retracted position. 
     Similarly, wall section  49  engages with rear end wall  54  when the housing is being retracted. Rear end wall  54  is perpendicularly mounted to wall  56  of telescopic portion  50 . When retracting the present invention, stopper tab  48  makes contact with wall  32  (and being lodged within cavity  33 ) to stop the retracting movement of telescopic portion  40 . Telescopic portion  50 , when retracted, fits within telescopic portion  40 . Similarly, front end wall  52 , perpendicularly mounted and slightly extending beyond wall  56 , includes outwardly extending tab  58  that makes contact with front end wall  42 . Wall section  59  engages with rear wall  64  when the housing is being retracted. In the preferred embodiment, tabs  48 ,  58  and  68  are received within cavities  33 ,  43  and  53 , respectively. In this manner, the front of portions  30 ,  40 ,  50  and  60  are flush when retracted, thereby retracting telescopic portion  40 . In the same manner, portion  60  fits within portion  50  and tab  68  makes contact with front end wall  52  when retracting. Additional telescopic portions may be added or deleted utilizing the system described above, depending on the requirements. 
     In FIG. 5 a portion of the engagement between portions  50  and  60  is shown. The primed numbers are used since they correspond to the opposite side as those shown in FIG.  4 . Stopper tab  68 ′ is received within cavity  53 ′. The engagement of wall  66 ′ with wall  56 ′ is water tight, in the preferred embodiment, or at least substantially water tight. This can be accomplished with a sealing member that could be foam  61  mounted, or equivalent material, on rear wall  64 , as shown in FIG.  6 . This is similarly done in rear walls  44  and  54  to accomplish the sealing function. 
     In FIG. 6 a detail of the engagement between telescopic portions  50  and  60  is shown in the expanded position. The relative dimensions of the different elements are represented a little exaggerated. Preferably tighter spacing and clearances provide a better and more volumetrically efficient structure. 
     FIGS. 7 and 8 represent another embodiment for the present invention, in expanded and retracted positions, respectively, where the portions have different dimensions to be used for another purposes, such as for protecting swimming pools P. This configuration may additionally include a hole  101  in surface S for storage purposes. Stationery portion  130  is rigidly mounted to wall  100 . Base member  102  is perpendicularly mounted to wall  100  and provided with hinge assembly  105  at one of its longitudinal vertex. In the retracted position, all the telescopic portions are housed within stationary portion  130 . Wall  100  can then be pivoted and brought to the same plane as surface S. The entire structure is hidden inside longitudinal cavity  101  returning usable area while providing storage convenience. Hole  101  is provided for convenient storage purposes. 
     Telescopic portions  40 ;  50  and  60 , once retracted, interlock each other through tabs  48 ;  58  and  68  and cavities  33 ;  43  and  53 . Portion  40  engages stationary portion  30  through tab  48  and cavity  33 . The group of these portions, being interlocked to each other, are then rotated inside base member  101  after removing pins  20 . Pins  20  have cooperative dimensions and strength characteristics to be inserted through loops  21  to withstand a predetermined weight of the entire assembly. To keep the different portions interlocked, pin member  25  is inserted through holes  24  in each one of portions  140 ;  150 ;  160 ;  170 ;  180 ;  190 ;  200 ;  210  and  220 , as seen in FIG.  7 . 
     Present invention  10  is made of a durable material such as fiberglass, aluminum or the like, and made to withstand natural weather elements, and intrusions such as flying objects (balls, etc.), trespassers or accidents that could damage the protected property. 
     The foregoing description conveys the best understanding of the objectives and advantages of the present invention. Different embodiments may be made of the inventive concept of this invention. It is to be understood that all matter disclosed herein is to be interpreted merely as illustrative, and not in a limiting sense.

Summary:
A retractable cover for protecting designated area and spaces. A stationary rigid portion receives telescopically extending portions movable over guiding assemblies to house vehicles and other objects and protect them. When the telescopic rigid portions are fully extended, they engage and interlock with seals resulting in a water tight structure. Also, the engagement is used to move and/or stop contiguous portions through the use of outwardly extending tabs at the rear and front ends of the telescopic portions. The guiding assemblies include channels through which wheels that are rotatably mounted to the lowermost ends of the portions. The stationary portion can be mounted to a cover member that is hingedly mounted to the area adjacent to a cooperative hole for selectively housing the retractable cover.