Abstract:
In an underground storage space, particularly for endangered goods, access is effected via a left the opening of which, leading into the storage space, can be closed by two covers which are arranged spaced apart from each other.

Description:
FIELD AND BACKGROUND OF THE INVENTION 
     The present invention relates to an underground storage space which is accessible via a lift. In previous underground storage spaces, there is a closing of the lift opening by a plate which travels on rollers. This requires expensive drive means and, in particular, measures for preventing a contamination, as by dirt, of both the travel paths and the drive means themselves. Furthermore, any damage to the closure plate from external sources may impair the operability of the closure plate. 
     SUMMARY OF THE INVENTION 
     The object of the invention is to create an underground storage space wherein the closing-off of the lift opening is substantially insensitive to dirt, while its operability is retained even in case of outer damage. Furthermore, actuation is to be effected with simple means. 
     In accordance with the invention, entrance to the storage space is attained by means of a lift. The lift opening is closed by a first cover having at least one swingable flap. A second cover closes the entrance below the first cover. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     With the above and other advantages in view, the present invention will become more clearly understood in connection with the detailed description of the preferred embodiments, when considered with the accompanying drawings of which: 
     FIG. 1 shows a cross section along the line I--I of FIG. 3; 
     FIG. 2 shows a cross section along the line II--II of FIG. 1; 
     FIG. 3 shows a cross section along the line III--III of FIG. 2, with flaps closed; 
     FIG. 4 shows a cross section along the line IV--IV of FIG. 3; and 
     FIG. 5 shows a cross section along the line III--III of FIG. 2, with flaps open. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In FIG. 1, 1 is the earth in which storage spaces 2, or rooms, have been excavated and limited by masonry wall 2a. The storage spaces 2 are accessible via a lift 3 having a platform 4 which can be lifted by four hydraulic work cylinders 5 from a lower storage level 6, shown in FIG. 1, into the upper entrance level (FIG. 5). The lift opening 8 is closed and opened by two covers 9 and 10 arranged spaced apart by a distance S. By the use of the two covers which are arranged spaced apart from each other, a tight closing of the lift opening is assured even if the upper cover is damaged by external causes. The upper cover 10 is formed in accordance with FIGS. 3 and 5 by two flaps 10a, 10b. On the sides of the flaps 10a, 10b facing the lift opening 8 there are fastened toothed sector gears 11, 12 which are in form-locked engagement with stationary racks 13, 14. The racks are fastened on foundations 15, 16. Piston rods 17, 18 of actuating cylinders 19, 20 are pivoted to the outer end 41 of each flap. As shown in FIG. 4, two toothed sector gears 11, 12 with racks 13, 14 and two actuating cylinders 19, 20 spaced apart from each other are associated with each of the flaps 10a, 10b. Bottoms of the cylinders 19, 20 are pivotally fastened on wall brackets 21, 22 (FIG. 5). The flaps 10a, 10b have counterweights 10c so that only slight hydraulic forces need be provided by the actuating cylinders for the swinging of the flaps. The actuating cylinders are arranged together with the toothed sector gears and racks in chambers 23, 24 separated by walls 23a, 24a, from the lift opening 8. Upon the retraction of the piston rods, the toothed sector gears fastened on the flaps roll on the racks so that the flaps swing into their open position shown in FIG. 5 and thus release the lift opening, a reverse direction of roll of the sector gears providing for a closing of the opening. 
     The four cylinders 5 for the raising and lowering of the lift are arranged in recesses 30 in the masonry wall 31 on the side of the lift and the cylinder bodies 5a are fastened via brackets 32 to the underframe 33 of the lift. The piston rods 5b have their ends 5c fastened to support members 34 fastened in supporting manner in the masonry wall. By the piston rods 5b which are arranged fixed in position and the cylinder bodies 5a which are movable with the lift, the piston rods are stressed in tension in advantageous manner. The cylinders 5 are so controlled via a distance-measurement system that their stroke movement takes place in synchronism upon a moving in and out of the piston rods. The operating fluid necessary for the actuating of the work cylinders 5, 19 is provided from a hydraulic storage station 36 (FIG. 1) which is fed by a hydraulic unit 37. Storage station 36 and hydraulic unit 37 are arranged in protected manner below the platform 4 on the bottom 6a of the storage space. 
     The lower cover 9 is fastened to the platform 4 of the lift via four rods 40 so that the cover rises and descends with the platform 4. In the lowered position of the platform 4, the cover 9 lies via its periphery on wall projections 2c (FIG. 3) and, by the interpositioning of a surrounding seal 46, seals the lift opening off from the outside. In this position of the platform, the latter is borne by the cover via the rods 40. In this way the weight of the lift can be used as sealing force for the sealing-off of the lift opening via the lower cover 9. 
     The outer ends 41 of the flaps 10a, 10b forming the upper cover 10 have an oblique course which, in the closed position of the flaps rests in sealing fashion against correspondingly obliquely extending wall projections 42. The facing ends 43 of the flaps have shoulders corresponding to each which lie against each other also in sealing manner in the closed position of the flaps. In this way, the space 44 between upper and lower covers is also substantially protected from external influences. The upper region 45, 46 (FIG. 3) of the partition walls between the lift opening 8 and the chambers 23, 24 receiving the actuating cylinders 20 with toothed sector gears 11, 12 and racks 13, 14 form a sealing body which, in the closed position of the flaps 10a, 10b, sealingly separates the chambers 23, 24 from the space 44 between the two covers 9 and 10.