AN INSPECTION DOOR FOR A FLAGGED COVERING OR CASING

Abstract: An inspection door for closing an inspection opening pro­ vided in a flagged covering or casing, said door incuding a flat removable cover plate (6) an a frame (4) carrying permanent magnets (5) for supporting said cover plate (6), said frame (4) and said cover plate (6) being made of sheet material having the same thickness, and said frame (4) with said cover plate (6) inserted having plane front surfaces lying flush with each other.

Description: The invention relates to an inspection door for closing an inspection opening provided in a flagged covering or casing, said door including a flat removable cover plate made from sheet steel and adapted to be covered with flags, and a surrounding structure adapted to be flagged and carrying permanent magnets for supporting said cover plate. An inspection door of this kind is known from DE-A-27 56 124. much known inspection door has the surrounding structure made of profile bars each having one profile leg to be flagged and another profile leg projecting into the gap between the flags of the flagged cover plate and the flagging surrounding the inspection opening, and said frame has off-set sheet strips projecting into the frame opening and carrying said permanent magnets which are in the form of cylindrical magnets having external threads and being screwed into associated tab holes of said off-set sheet strips. Every paviour knows the difficulties in mounting such or similar inspection doors so as to achieve a properly flush closure of the inspection opening with the flags of the inspection door being properly integrated into the gap pattern of the surrounding flagging. However, this is difficult with the just mentioned prior art inspection door and with other commercial inspection doors as well. The profile legs projecting into the gap between the inspection door and the surrounding flagging reduces the possible extent of correction of the flags covering the cover plate, on the one hand, and requires to provide gaps of excessive width in the region of the inspection door, on the other hand, and, furthermore, the proper adjustment of the position of the four magnets will often be achieved only after multiple sequences of trial and troublesome removal of the cover plate failing to take a properly flush position. Despite of this, manufacturing of said prior art inspection door is expensive and requires numerous parts, and proper mounting is time-consuming and difficult. DE-U-76 28 284 suggests to prepare a cover arrangement for an inspection opening using a number of magnet carrying sheet metal elements which are affixed to the rear side of at least some of the flags surrounding the inspection opening prior to mounting said flags to the wall, and using a corresponding number of planar sheet metal pieces which are affixed to the rear side of the cover at locations corresponding to the locations of the magnets projecting into the inspection opening. While there are no parts of said sheet metal elements projecting into the gap between the cover and the surrounding flagging, proper mounting of this prior art arrangement may require considerable skill and may be troublesome. Therefore, it is the object of the present invention to provide an inspection door of the kind in question so as to allow for quick and easy mounting independently of the thickness of the flags and to be convenient and inexpensive in respect to manufacture while forming, when mounted, an unconspicious closure of the inspection opening. In accordance with the present invention, this object is achieved by an inspection door as characterized in any of independent claims 1 to 3. The common idea behind all of these three alternatives is the provision of a flat prefabricated frame made as a sheet construction of sheet material having the same thickness as the sheet steel cover plate and providing together with the cover plate a flush planar front surface. The inspection door according to the invention lends itself especially for use in laying flags in a thin layer of cement and, because of its easy mounting, is cut out specifically for do-it-yourself workers who can make a proper flagging without specific technical knowledge and without special mechanical skill. The inspection door according to the invention has the frame and the cover plate lying in a common plane, that is flush with each other so that mounting is performed simply by inserting the frame in the region of the edges of the inspection opening flush with the substrate to be flagged, and the frame and the cover plate can then be covered with flags, whereby a flush position of the flagged cover plate with the surrounding flagging can be achieved without any special adjustment and totally independently of the respective thickness of the flags. Due to the absence of any webs of the frame projecting into the gap between the cover plate and the surrounding flagging, the cover plate together with its flagging can be properly integrated into the flag pattern, and permanently elastic gap filler can then be injected into the gap and, when the inspection door needs to be opened, can be scraped out and renewed thereafter. Thus, the mounted inspection door is air- and water-tight. The inspection door according to the invention can be manufactured in a very easy and inexpensive manner because, except for the magnets and, if need be, their mountings attached to the rearside of the frame, it consists only of flat sheet material. According to claim 1, the frame consists of two planar sheet strips to be mounted at opposite sides of the inspection opening, said two strips being rigidly connected to each other by two planar transverse bars attached to their rearsides. This allows for easy manufacture of the frame without punching out any large opening and, simultaneously, allows for easy mounting of the inspection door. Alternatively, in accordance with claim 2 the frame is formed by a sheet plate having a central opening corresponding to the size of said cover plate. In case of large piece numbers, this alternative constitutes the best method of manufacture and results in a frame construction which is rigid in itself. Preferably, said magnets each are attached to the rearside of the frame in such a manner that their support surfaces for said cover plate are flush with the backside of the frame and project beyond the inner edges of the frame into the frame opening. Said magnets can be made as flat magnets, each of them being attached with one edge thereof to the rearside of the frame, or being arranged diagonally at one corner of said frame opening. Preferably, said magnets are attached to the rearside of the frame by adhesive. Alternatively, each of said magnets can be mounted in a recess of a bar or of a lug attached to the rearside of said frame and crossing said frame opening or extending into said frame opening. Each of said magnets can be adjustably mounted in a tab hole of said bar or lug. In a preferred embodiment of the invention in accordance with claim 3, two opposite sheet strips of said frame have their edge portions adjacent to said frame opening off-set backwards by the amount of the sheet thickness so as to form additional support surfaces for said cover plate, said additional support surfaces extending substantially along the full length of the respective two opposite edges of the cover plate, thus rendering installation of the inspection door even more easy and improving proper and flush support of the cover plate. In this embodiment, the magnets can be mounted in recesses of said off-set edge portions. Some examples of embodiments of the invention are shown in the accompanying drawings and are described hereinafter in more detail. In the drawings, fig. 1 is a cross-sectional view of an inspection door according to the invention mounted in a flagged covering, fig. 2 is a top view of an embodiment of an inspection door according to the invention, fig. 3 is a top view of an alternative embodiment of an inspection door according to the invention, figs. 4, 5 and 6 are top views of the frame of the inspection door with various alternatives of mounting the magnets, and fig. 7 a further embodiment of an inspection door according to the invention. Fig. 1 shows an inspection door 3 constructed according to the invention and mounted at a flagged wall across an inspection opening 2, the inspection door consisting of a frame 4, of permanent magnets 5 attached thereto, and of a cover plate 6. Frame 4 is, using a bed of mortar 7 for instance, mounted into wall 1 at the border of inspection opening 2 flush with wall surface 1a to be flagged. Permanent magnets 5 in the form of flat magnet bodies each have its edge portion attached to the rearside of the frame, by means of adhesive for example, and they project beyond the inner edges of the frame into the inspection opening, each magnet's support surface 5a for supporting the cover plate 6 being flush with the rearside of the frame. Frame 4 and cover plate 6 are both made from sheet steel of the same thickness, thus rendering the front surfaces of frame 4 and cover plate 6 flush with each other and also with outer wall surface 1a when cover plate 6 is inserted. After flagging with a thin layer of cement 8, flags 9 attached to the wall around inspection opening 2 and flags 10 attached to cover plate 6 ly flush with each other. The gaps between flags 10 of the cover plate and the surrounding flags 9 have a permanently elastic gap filler 11 injected therein which, when the inspection door needs to be opened, will be scraped out and renewed thereafter. Opening of the inspection door can easily be performed using a suction apparatus as known per se. Fig. 2 shows a top view of the inspection door according to fig. 1 in a smaller scale, wherein the flagging is indicated in dotted lines only. Frame 4 consists of a sheet plate in which a central opening 4a is punched out for receiving cover plate 6 with some clearance. Four magnets 5 are each diagonally mounted at the four corners of frame opening 4a. Fig. 3 shows a modified embodiment of the inspection door in which the frame is made from two sheet strips 41 and 42 extending at opposite sides of cover plate 6. Each of said two sheet strips has two magnets 5 attached to its rearside at its edge region extending towards the inspection opening. Said two sheet strips 41 and 42 constituting said frame can be connected to each other by two transverse bars 43 shown in dotted lines, which bars each are attached to the backside of said two sheet strips 41 and 42, such as by spot welding, to joint them to a rigid frame construction allowing for easy mounting. Figs. 4, 5 and 6 show various alternatives of mounting the magnets to the frame. The embodiment according to fig. 4 has short bars 52 each extending diagonally across the corner region of the frame opening and attached to the rearside of frame 4, with a magnet 51 being inserted into a recess of bar 52 and attached thereto. Fig. 5 shows a modified arrangement in which lugs 55 are attached to the rearside of frame 4, each of said lugs carrying one magnet 51 inserted into a recess thereof. Fig. 6 shows a frame similar to that of fig. 3 consisting of two sheet strips 41 and 42 connected to each other by two transverse bars 52 carrying two magnets 51 each inserted into recesses thereof. Fig. 7 shows a top view of a preferred embodiment of the frame 4 of the inspection door wherein the frame consists of two opposite sheet strips 45 and 46 having their edge portions 45a, 46a adjacent to frame opening 4a off-set backwards by the amount of the sheet thickness (see cross-sectional profile P of said sheet stripes drawn into the top view of sheet strip 46), and of two planar-sheet strips 47 and 48 attached by spot welding to the front surfaces of said off-set edge portions 45a and 46a of said first-mentioned sheet strips 45 and 46. The magnets 51 may be mounted in recesses of said off-set edge portions 45a and 46a or may be attached to the frame in any other way.

Claims: An inspection door for closing an inspection opening provided in a flagged covering or casing, said door including a flat removable cover plate (6) made from sheet steel and adapted to be covered with flags, and a surrounding structure (4) adapted to be flagged and carrying permanent magnets (5) for supporting said cover plate (6), characterized in that said surrounding structure (4) is a frame and is made as a sheet construction of sheet material having the same thickness as said cover plate and consisting of two planar sheet strips (41, 42) arranged at two opposite edges of said cover plate and rigidly connected to each other by means of two planar transverse bars (43) attached to the rear surface thereof, and in that said magnets (5) are mounted so as to support said cover plate (6) flush with the planar front surface of said frame (4). An inspection door for closing an inspection opening provided in a flagged covering or casing, said door including a flat removable cover plate (6) made from sheet steel and adapted to be covered with flags and a surrounding structure (4) adapted to be flagged and carrying permanent magnets (5) for supporting said cover plate (6), characterized in that said surrounding structure (4) is a planar frame and is made as a sheet construction of sheet material having the same thickness as said cover plate and is formed by a sheet plate having a central opening (4a) corresponding to the size of said cover plate (6), and in that said magnets (5) are mounted so as to support said cover plate (6) flush with the planar front surface of said frame (4). An inspection door for closing an inspection opening provided in a flagged covering or casing, said door including a flat removable cover plate (6) made from sheet steel and adapted to be covered with flags, and a surrounding structure (4) adapted to be flagged and carrying permanent magnets (5) for supporting said cover plate (6), characterized in that said surrounding structure (4) is a frame and is made as a sheet construction of sheet material having the same thickness as said cover plate and consisting of two planar sheet strips (45, 46) arranged at two opposite edges of said cover plate, said opposite sheet strips being provided with opposing planar edge portions which are off-set backwards by the amount of the sheet thickness, and said opposite sheet strips being connected by two planar sheet strips (47, 48) attached by spot welding to the front surface of said off-set edge portions, and in that said magnets (51) are mounted so as to support said cover plate (6) flush with the planar front surface of said frame (4). An inspection door according to claim 1 or 2, characterized in that said magnets (5) are each attached to the rear side of the frame (4) in such a manner that their support surfaces (5a) for said cover plate (6) are flush with the rear surface of the frame and project beyond the inner edges of the frame into the frame opening. An inspection door according to claim 4, characterized in that said magnets (5) are made as flat magnets, each of them being attached along an edge thereof to the rear side of said frame. An inspection door according to claim 4, characterized in that said magnets (5) are made as flat magnets each being arranged diagonally at one corner of said frame opening (4a). An inspection door according to any of claims 1 to 3, characterized in that each of said magnets (51) is mounted in a recess of a bar (52) attached to the rear side of said frame and crossing said frame opening (4a). An inspection door according to any of claims 1 to 3, characterized in that each of said magnets (51) is mounted in a recess of a lug (55) attached to the rear side of said frame and extending into said frame opening (4a). An inspection door according to claim 3, characterized in that said magnets (51) are mounted in recesses of said offset edge portions (45a, 46a).

Inventors: ERTL, ARMIN, REICHHOLD, ALFRED
Applicants: ERTL, ARMIN, REICHHOLD, ALFRED
Application year: 1986
Main classification: E04F19
IPC codes: E04F19