Ceiling construction

A ceiling construction for buildings has a plurality of flanged main beams disposed in a predetermined spaced relationship to each other and bridging wall mouldings opposed and spaced from each other; a plurality of flanged cross beams connected to the main beams in a predetermined spaced relationship to each other at right angles to the main beams so as to form a ceiling framework; a ceiling wall mounted on the ceiling framework so as to form an access opening in a predetermined position; a pair of auxiliary beams; a plurality of fastening devices for the auxiliary beams; an access door; and a plurality of mounting devices for the access door. The pair of auxiliary beams each is bridged in a predetermined relationship to flanges the opposite main beams of the main beams adjacent to and spaced from each other or flanges of the opposite cross beams of the cross beams adjacent to and spaced from each other in the access opening on the ceiling wall. Further, the opposite ends of the auxiliary beams are secured to one of the main and cross beams by the fastening devices. Furthermore, the access door is positioned in the access opening, and is secured to the ceiling frame work by the use of the auxiliary beams and mounting devices.

BACKGROUND OF THE INVENTION 
This invention relates to a ceiling construction for buildings and more 
particularly, to an improved ceiling construction having a ceiling 
framework which comprises a plurality of main beams and a plurality of 
cross beams. 
Within recent years, ceiling constructions erected by the exposed, 
concealed and dry wall construction methods have been popularized. 
The ceiling framework of the ceiling construction erected by any one of the 
three known construction methods comprises a grid system which comprises a 
plurality of flanged main beams and a plurality of flanged cross beams 
interconnected at right angles to each other to form a grid formation. In 
the ceiling construction erected by the exposed construction method, the 
ceiling boards which constitute the ceiling wall are fitted in the grid 
and laid on the flanges on the main and cross beams in the grid. In the 
ceiling construction erected by the concealed construction method, the 
ceiling boards which constitute the ceiling wall are positioned in the 
grid with the flanges on the main beams received in the grooves formed in 
the end faces of the ceiling boards. In the ceiling construction erected 
by the dry wall construction method, the ceiling boards which constitute 
the ceiling wall are secured to the main and cross beams by means of nails 
or screws in the grid. The ceiling construction usually includes an access 
door, but in the ceiling construction erected by the exposed construction 
method, since the ceiling boards can be easily removed, such a ceiling 
construction is not provided with the access door. In the ceiling 
construction erected by the concealed construction method, the ceiling 
boards are mounted on the main beams by the employment of access angles 
and hooks in suitable positions on the ceiling whereby the ceiling boards 
can be removed and thus, as in the case of the ceiling construction 
erected by the exposed construction method, in the ceiling construction 
erected by the concealed construction method, the access door is not 
usually employed. However, when the ceiling boards are designed to be 
removed, as the ceiling boards are removed and reinstated, the ceiling 
boards tend to be damaged or smeared leading to undesirable results. 
In the ceiling construction erected by the dry wall construction method, 
since the ceiling boards are not detachable, the access door is disposed 
in the access opening formed in a suitable position of the ceiling 
surface. In such a case, taking the weight of the access door into 
consideration, the access door is attached to the frame channel bound to 
hanger wires secured to the ceiling slabs by wire fasteners or attached to 
the frame channel bound to the main beams. In such an access door mounting 
arrangement, the construction method of the ceiling construction is very 
troublesome. Especially, when the frame channel is directly hung from the 
ceiling slabs and the access door is attached to the frame channel, after 
a prolonged use of the ceiling construction, an undesirable step is formed 
between the access door and ceiling wall. 
SUMMARY OF THE INVENTION 
Therefore, one object of the present invention is to provide a ceiling 
construction for buildings which can be easily erected by the exposed, 
concealed or dry wall construction method. 
Another object of the present invention is to provide a ceiling 
construction for buildings which is reinforced and is prevented from 
warping both in the horizontal and vertical directions under the load of 
the access door as the access door is opened and closed, and which 
prevents any strain or deflection in the grids of the ceiling 
construction. 
A further object of the present invention is to provide a ceiling 
construction for buildings which allows the access door to open and close 
smoothly, in which when the access opening where the access door is 
positioned opens to the ceiling wall, the ceiling wall is prevented from 
lifting from the ceiling framework of the ceiling construction, which can 
be easily applied to the ceiling wall of different thicknesses and 
materials, and which can be easily and simply constructed in a brief 
period, and has an improved finish. 
For attaining the above objects, the present invention provides a ceiling 
construction for buildings which comprises 
a plurality of flanged main beams disposed in a predetermined spaced 
relationship to each other and bridging wall mouldings opposed and spaced 
from each other; 
a plurality of flanged cross beam connected to said main beams in a 
predetermined spaced relationship to each other at right angles to the 
main beams so as to form a ceiling framework; 
a ceiling wall mounted on said ceiling framework so as to form an access 
opening in a predetermined position; 
a pair of auxiliary beams each bridging in a predetermined relationship 
flanges of the opposite main beams of said main beams adjacent to and 
spaced from each other or flanges of the opposite cross beams of said 
cross beams adjacent to and spaced from each other in said access opening 
on said ceiling wall; 
a plurality of fastening means securing the opposite ends of said auxiliary 
beams to one of said main and cross beams; 
an access door positioned in said access opening and comprising a 
stationary framework having an outwardly extending flange, a movable 
framework rotatably connected to said stationary framework and a cover 
plate fixedly secured to said movable framework; and 
a plurality of mounting means securing said access door to said ceiling 
framework so as to put the access door opening defining edge of the 
ceiling wall between said auxiliary beams and said outwardly extending 
flanges on the stationary framework. 
The advantages offered by the invention are mainly that various 
construction methods such as the exposed, concealed and dry wall 
construction methods can be easily applied, that the ceiling is reinforced 
and reduced in weight, that even through the weight of the ceiling is 
reduced the ceiling is prevented from warping in the horizontal and 
vertical directions under the load of the access door, that any strain or 
deflection in grids of the ceiling framework is prevented and that 
especially, if the access door is suddenly opened and closed, any flapping 
phenomenon or vibration of the ceiling under the load of the access door 
is prevented. Therefore, the ceiling construction for buildings which has 
the above-described arrangement of the components is of practical use. 
Thus, since the ceiling construction of the present invention is provided 
with reinforcing means, the ceiling construction is versatilely erected by 
the exposed, concealed and dry wall construction methods and especially, 
very suitable for a broad building ceiling.

DETAILED DESCRIPTION OF THE INVENTION 
The present invention will be now described referring to the accompanying 
drawings and more particularly, to FIGS. 1 through 5 in which the 
preferred embodiment of the ceiling construction for buildings erected in 
accordance with the present invention is shown in a fragmentary 
perspective view. 
The ceiling construction 10 is erected by the exposed construction method 
and in a predetermined spaced relationship the opposite wall mouldings 
(not shown) secured to the ceiling wall of a building in a square 
arrangement and hung in suitably spaced positions on the ceiling slabs by 
means of hanger wires or hanger rods (not shown), a plurality of cross 
beams 12 extending between the main beams 11 and connected to the main 
beams 11 in a predetermined spaced relationship and also extending between 
and connected to the main beams 11 and the associated wall mouldings at 
right angles thereto so as to form a square ceiling framework, a ceiling 
wall 13 laid on the flanges of the main and cross beams 11, 12 in the 
ceiling framework to define an access opening 21 in a selected grid of the 
ceiling framework, a pair of auxiliary beams 14 disposed on the inner 
surface of the ceiling wall 13 in the access opening 21 and bridging in a 
predetermined spaced relationship the flanges of one pair of opposite main 
beams 11 of the main beams 11, four fastening means 15 securing the 
auxiliary beams 14 at their opposite ends to the pair of opposite main 
beams 11, an access door 16 positioned in the access opening 21 and four 
mounting means 17 securing the access door 16 to the ceiling framework so 
as to sandwich the access opening defining edge 22 of the ceiling wall 13 
between the auxiliary beams 14 and access door 16. 
The main beam 11 is formed by rolling a length of metal band such as band 
steel, aluminum alloy or stainless steel having a T-shaped cross-section 
and has end couplings (not shown) at the opposite ends. A number of the 
rolled metal bands are end to end connected by the end couplings to form 
the main beam having a suitable length depending upon the dimensions of 
the building ceiling. 
Similarly, the cross beam 12 is formed by rolling a length of metal band 
such as band steel, aluminum alloy or stainless steel having a T-shaped 
cross-section and has a length in conformity with the span between the 
opposite main beams 11 or between one main beam 11 and the adjacent wall 
moulding and the cross beam 12 has twisted clips or hook clips (not shown) 
at the opposite ends so that the cross beam 12 can be connected to the 
associated main beams 11 or the adjacent main beam 11 and wall moulding. 
The ceiling wall 13 is formed by arranging in succession a plurality of 
ceiling tiles 23 cut to a desired size between the flanges 19 on the main 
and cross beams 11, 12 and between one of the main beams 11 or cross beams 
12 and the adjacent wall moulding. 
The material of the ceiling tile 23 is, of course, selected depending upon 
the specification of the tile and may be replaced by a cement board having 
heat-resisting fiber mixed therewith, a wooden board or a board having 
sound absorption material mixed therewith. 
Each of the pair of auxiliary beams 14 is formed of a length of I-cross 
section steel piece slightly shorter than the span between the opposite 
main beams 11. The auxiliary beam 14 may be, of course, formed by rolling 
a length of band steel. 
The fastening means 15 comprises a pressure plate 24 urging the auxiliary 
beam 14 at the adjacent end thereof as well as the adjacent ceiling wall 
13 against the flange 19 on the associated main beam 11, a clamping plate 
25 securing the pressure plate 24 to the web 18 of the associated main 
beam 11 and a headed screw and wing nut arrangement 26, 27 securing the 
clamping plate 25 to the pressure plate 24. 
The pressure plate 24 is formed at the lower end with a horizontally bent 
foot 28 and at the upper end with an elongated slot 29. The bent portion 
of the foot 28 is reinforced with a bead 30. 
The clamping plate 25 is adapted to be employed in abutment against the 
pressure plate 24 and formed at the lower end with a hook 31 for engaging 
a rectangular bulb 20 on the associated main beam 11 and at the upper end 
with a hole (not shown) for receiving the headed screw 26. 
The access door 16 is fitted in the access opening 21 and comprises a 
stationary framework 32 secured to the ceiling framework by mounting means 
17 in cooperation the ceiling wall 13 and auxiliary beams 14, a movable 
framework 33 disposed within the opening 34 defined by the stationary 
framework 32 and secured to the stationary framework 32 for rotation 
relative to the stationary framework 32, a cover plate 36 fixedly secured 
to the movable framework 33 by means of set screws for normally closing 
the opening 35 defined by the movable framework 33, a pair of bearings 37 
projecting inwardly or towards each other from the opposite inner surfaces 
of the stationary framework 32, a pair of shafts 38 extending through the 
opposite sides of the movable framework 32 and journalled in the bearings 
37 and a cremorne lock 39. With the above-mentioned arrangement of the 
components of the access door 16, when the movable framework and cover 
plate assembly 33, 36 and more particularly, the cover plate 36 is in the 
closed position, the cover plate 36 is locked to the stationary framework 
32 by the cremorne lock 39. When the cremorne lock 39 is unlocked, the 
cover plate 36 is allowed to rotate downwardly to the open position by 
means of the bearings 37 and shafts 38. 
The stationary framework 32 comprises four identical extruded aluminum 
frame members cut to a selected length and assembled in a square 
arrangement. More particularly, each of the four frame members of the 
stationary framework 32 includes a web 40 and an outwardly extending 
flange 41 integrally formed with the lower end of the web 40 to define the 
opening 34. The web 40 and flange 41 define lower and upper grooves 42, 
43, 44 at the lower end upper ends of the frame member, respectively, for 
the purpose to be described hereinafter. The stationary framework 32 is, 
of course, formed by assembling four identical frame members of a selected 
length each including the web, the flange integrally formed with the upper 
end of the web and defining grooves on the opposite sides of the web and 
the flange integrally formed with the lower end of the web and defining a 
groove on one side of the web together by the use of four identical steel 
corner pieces at the four corners of the stationary framework 32. 
Similarly, the movable framework 33 comprises four identical extruded 
aluminum alloy frame members cut to a selected length and assembled in a 
square arrangement. More particularly, each of the four frame members of 
the movable framework 33 includes a web 45 and an outwardly extending 
flange 46 integrally formed with the lower end of the web to define the 
opening 35. The web 45 and flange 46 define lower and upper grooves 47, 48 
at the lower end upper ends of the frame member on one side thereof. The 
movable framework 33 is, of course, formed by assembling four identical 
frame members of a selected length each including the web and the flange 
integrally formed with the lower end of the web to define lower end upper 
grooves on one side of the frame member and held together by the use of 
four identical steel corner pieces at the four corners of the movable 
framework. 
The cover plate 36 comprises some of the ceiling tiles 23 and is laid on 
the inside of the outwardly extending flanges 46 of the movable framework 
33. The cover plate 36 is fixedly secured to the movable framework 33 by 
means of a plurality of securing means and screw arrangement. 
Each of the bearings 37 includes a substantially U-shaped bearing face 50 
with a bearing groove 49 and a pair of inward bulges 52 of small 
dimensions in the upper opening 51 of the bearing groove 49. 
The provision of the pair of inward bulges 52 on the bearing face 50 
narrows the upper opening 51 of the bearing groove 49 and thus, the 
associated shaft 38 is snapped into and out of the bearing 37. 
Furthermore, the bearing 37 includes a plate-like bracket 53 integrally 
formed with one end thereof so that the bearing 37 can be easily attached 
to the stationary framework 32 whereas the other end of the bearing 37 is 
positioned adjacent to the web 45 of the adjacent frame member of the 
movable framework 33. The lower portion of the bearing 37 forms a stop for 
the outwardly extending flanges 46 of the movable framework 33 and the end 
face at the other end of the bearing 37 serves to prevent the rocking of 
the movable framework 33. 
The bearing 37 is usually integrally formed together with the bracket 53 
from polyamide resin or fluorinated resin, but can be also formed of 
bearing alloy. 
Each of the pair of shafts 38 is provided at one end with a sleeve of 
reduced outer diameter to extend through the pin hole formed in the 
adjacent corner piece associated with the movable framework 33. The 
extended sleeve is caulked against the corner piece and secured thereto. 
Thus, when the movable framework 33 is formed of the four frame members and 
the four corner pieces including the corner piece against which the shaft 
38 is caulked, the shafts 38 is attached to the movable framework 33. 
The cremorne lock 39 is disposed on the movable framework 33 and comprises 
a pair of locking rods 54 having the leading ends guided by guides 58 for 
extending from the movable framework 33 to the stationary framework 32 and 
vice versa, a pair of rod bearings 55 disposed on the stationary framework 
32 for receiving the leading ends of the locking rods 54, an operation 
plate 56 rotatably held on the cover plate 36 and connecting the locking 
rods 54 together and a crank shaft 57 for rotating the operation plate 56 
from outside of the cover plate 36. The cremorne lock 39 is conventional. 
And the cremorne lock 39 may be replaced by any other conventional locking 
device. 
Each of the securing means 17 comprises a carrier plate 59 holding the 
access door 16 or stationary framework 32 on the associated auxiliary beam 
14 and a threaded clamping bar 60 securing the carrier plate 59 to the 
auxiliary beam 14 so as to sandwich the access opening defining edge 22 of 
the ceiling wall 13 between the associated auxiliary beam 14 and the 
outwardly extending flange 41 of the adjacent frame member of the 
stationary framework 32. 
The carrier plate 59 extends along the inner surface of the web 40 of the 
adjacent frame member of the stationary framework 32 and includes at the 
lower end a plate like hook 61 to be received in the groove 44 in the 
adjacent stationary framework frame member and at the upper end a bent arm 
62. The arm 62 has a threaded hole (not shown) for receiving the 
associated threaded clamping bar 60. Thus, the carrier plate 59 and 
threaded clamping bar 60 are previously assembled together so that the 
access door 16 can be easily secured to the movable framework 33. 
The assembly of the ceiling construction 10 having the afore-mentioned 
construction and arrangement of the components will be now described. 
First of all, the wall mouldings are attached to the concrete ceiling wall 
of a room in a building in accordance with a predetermined layout by the 
use of concrete nails, a plurality of wire fasteners are driven into the 
ceiling slabs in a suitably spaced relationship and hanger wires are 
hooked to the wire fasteners. 
Thereafter, a plurality of main beams 11 each comprising a number of beam 
members end to end connected by the end couplings at the ends of the 
members to a predetermined length are bridged in a spaced relationship 
between the respectively adjacent wall mouldings in one plane, the main 
beams 11 are bound to the hanger wires and the main beams 11 are secured 
at the opposite ends to the wall mouldings by screws. 
Thereafter, a plurality of cross beams 12 are bridged in a spaced 
relationship between the opposing main beams 11 and between the associated 
main beams 11 and wall mouldings at right angles to the main beams 11, and 
the cross beams 12 are connected to the main beams 11 by the twisted clips 
and to the wall mouldings by the screws to thereby form a grid-shaped 
ceiling framework. 
After the ceiling framework has been formed by the wall mouldings, main 
beams 11 and cross beams 12 in the manner described hereinabove, a 
plurality of ceiling tiles 23 of suitable shape are in succession arranged 
between the flanges 19 on the opposing main beams 11, between the flanges 
19 on the opposing cross beams 12, between the flanges 19 on the 
associated main beams 11 and wall mouldings and between the flanges 19 on 
the associated cross beams 12 and the wall mouldings, respectively, and 
the access opening 21 is formed in a selected grid of the ceiling 
framework to thereby form the ceiling wall 13. 
Thereafter, the pair of auxiliary beams 14 are bridged between the flanges 
19 on the opposing main beams 11 on the inside of the ceiling wall 13 and 
secured at the ends thereof to the main beams 11 by the fastening means 
15. 
That is, in the fastening means 15, since the pressure plate 24 and 
clamping plate 25 are temporarily assembled together by means of the screw 
26 and wing nut 27, the hook 31 is fitted on the rectangular bulb 20, the 
clamping plate 25 is hooked on the associated main beam 11, the bent foot 
28 is pressed against the associated auxiliary beam 14 by sliding the 
pressure plate 24 along the clamping plate 25, the wing nut 27 is fastened 
to secure the auxiliary beam 14 to the associated main beam 11 and at the 
same time the auxiliary beam 14 as well as the ceiling wall 13 is pressed 
against the flange 19 on the associated main beam 11 to thereby finally 
secure the auxiliary beam 14 to the ceiling framework. 
After the auxiliary beams 14 have been secured to the ceiling framework by 
the fastening means 15 in the manner described hereinabove, the stationary 
framework 32 having the access door 16 or the movable framework 33 removed 
therefrom previously is fitted in the access opening 21 and pushed into 
the access opening 21 until the outwardly extending flanges 41 on the 
stationary framework 32 abut against the access opening defining edge 22 
whereupon the stationary framework 32 is temporarily secured to the 
auxiliary beams 14 by means of the four mounting means 17. 
That is, the hooks 61 are fitted in the grooves 44 by sliding the hooks 61 
along the webs 40 on the frame members of the stationary framework 32 
fitted in the access opening 21 on the inside of the framework, the 
carrier plates 59 are hooked on the stationary framework 32 and the 
stationary framework 32 is temporarily secured to the auxiliary beams 14 
by the four mounting means 17 with the leading ends of the threaded 
clamping bars 60 riding on the auxiliary beams 14. 
After the temporary securing of the stationary framework 32 to the 
auxiliary beams 14 in the manner described above, the threaded clamping 
bars 60 are turned in the fastening direction to sandwich the access 
opening defining edge 22 of the ceiling wall 13 between the outwardly 
extending flanges 41 on the frame members of the stationary framework 32 
and the auxiliary beams 14 to thereby assemble the stationary framework 32 
to the ceiling framework. 
After the assembly of the stationary framework 32 to the ceiling framework 
in the manner described above, the movable framework 33 having the cover 
plate 36 attached thereto is inserted into the opening 34 defined by the 
stationary framework 32 while the shafts 38 are being snapped in the 
bearings 37 to thereby assemble the movable framework 33 to the stationary 
framework 32 for rotation relative thereto. Thereafter, the movable 
framework 33 is rotated upwardly to close the opening 34 defined by the 
stationary framework 32 and the movable framework 33 and accordingly, the 
cover plate 36 of the movable framework is locked against the stationary 
framework 32 by the cremorne lock 39. 
Although the ceiling construction 10 is erected on the ceiling of the 
building room in the manner described above, the ceiling construction may 
be erected in various different ways depending upon the conditions within 
the building room or the conditions at the construction site. 
FIGS. 6 through 13 show modified fastening means which can be employed in 
the ceiling construction as shown in FIGS. 1 through 5. In the modified 
fastening means 70 of FIGS. 6 through 9, the bent foot 28 of the 
afore-mentioned fastening means 15 has on the upper surface thereof a 
raised tongue 71 which has been provided by cutting and bending a portion 
of the foot to the shape as shown in these Figures. By the provision of 
the tongue 71 on the foot 28, even when the auxiliary beams 14 have a 
length somewhat shorter than the span between the flanges 19 on a pair of 
opposing main beams 11, the fastening means 70 can positively secure the 
opposite ends of the auxiliary beams 14 to the flanges 19 on the main 
beams 11. 
FIGS. 6 and 7 show the modified fastening means 70 as applied to a ceiling 
construction erected by the exposed construction method, FIG. 8 shows a 
modified fastening means 70 as applied to the ceiling construction erected 
by the dry wall construction method and FIG. 9 shows a modified fastening 
70 as applied to the ceiling construction erected by the concealed 
construction method, respectively. 
FIGS. 10 and 11 show a modified fastening means 80 as applied to the 
ceiling construction erected by the exposed construction method and the 
fastening means 80 comprises a threaded pressure bar 81 pressing the 
associated auxiliary beam 14 as well as the ceiling wall 13 against the 
flange 19 on the associated main beam 11 at the adjacent end of the 
auxiliary beam 14, a clamping plate 82 having a horizontal arm 84 provided 
with a threaded hole in threaded engagement with the threaded pressure bar 
81 and a hook 85 for engaging the rectangular bulb 20 on the associated 
main beam 11 and a carrier plate 83 holding the clamping plate 82 on the 
ceiling wall 13. 
The pressure clamping plate 82 has an elongated slot 86 formed in the hook 
85 and a slit 87 in the arm 84 for receiving the carrier plate 83. The 
slit 87 is formed by cutting and bending uprightly a portion of the arm 84 
to provide a tongue 88. 
And when received in the slit 87, the carrier plate 83 extends uprightly 
along the upright tongue 88 with the foot 89 on the carrier plate 83 
riding on the ceiling wall 13. 
With the above-described construction and arrangement of the components of 
the fastening means 80, the auxiliary beams 14 can be positively secured 
to the ceiling framework by means of the fastening means regardless of 
whether the ceiling construction where the fastening means 80 is 
incorporated is erected by the exposed, concealed or dry wall construction 
methods. 
The modified fastening means 90 shown in FIGS. 12 and 13 is applicable to 
the ceiling construction erected by the exposed construction method and 
the fastening means 90 comprises a threaded pressure bar 91 pressing the 
associated auxiliary beam 14 as well as the ceiling wall 13 against the 
flange 19 on the associated main beam 11 at the adjacent end of the 
auxiliary beam 14, a clamping plate 92 having an arm 94 provided with a 
threaded hole in threaded engagement with the threaded pressure bar 91 and 
a hook 95 engaging the rectangular bulb 20, an auxiliary plate 92 applied 
against the clamping plate 92 and a headed screw and wing nut arrangement 
26, 27 securing the auxiliary plate 93 to the clamping plate 92. 
The arm 94 of the clamping plate 92 is formed by cutting and bending 
uprightly a portion of the hook 95 and provided with a threaded hole 96 in 
threaded engagement with the pressure threaded bar 91. The arm 94 is, of 
course, reinforced with bead. 
Like the fastening means 15, the modified fastening means 90 can also 
positively secure the auxiliary beam 14 to the ceiling construction 
regardless of whether the ceiling construction is constructed by the 
exposed, dry wall or concealed construction methods. 
From the foregoing description of the invention, it will be understood that 
as compared with the previously proposed and existing ceiling 
constructions for buildings, since, in the ceiling construction for 
buildings according to the present invention, the ceiling framework 
comprises a plurality of main beams bridging wall mouldings and hung on a 
plurality of hanger wires or hanger rods and a plurality of cross beams 
bridging the main beams and the wall mouldings and main beams, 
respectively, and the ceiling wall is mounted on the ceiling framework to 
form the access opening in a predetermined position of the ceiling wall, 
and the auxiliary beams are bridged in a predetermined relationship 
flanges of the opposite main beams or flanges of the opposite cross beams 
in the access opening on the ceiling wall, and the fastening means secure 
the opposite ends of the auxiliary beams to the main and cross beams, and 
the mounting means secure the access door in the access opening so as to 
sandwich the access opening defining edge of the ceiling wall between the 
auxiliary beams and the outwardly extending flanges on the stationary 
framework, the present invention can be advantageously applied to various 
ceiling constructions to be constructed by the exposed, concealed and dry 
wall construction methods, the ceiling construction is reinforced, the 
ceiling construction is prevented from warping in the horizontal and 
vertical directions under the load of the access door as the access door 
is opened and closed, any deflection or strain in the ceiling framework is 
prevented, even when the access opening where the access door is 
positioned opens to the ceiling wall, the ceiling wall is positively 
prevented from lifting from the ceiling framework of the ceiling 
construction, the ceiling construction is easily applicable to ceiling 
wall of different thickness and materials and can be constructed in a 
brief period, and in addition, the ceiling construction gives improved 
finish to the building ceiling. 
As clear from the foregoing description of preferred embodiments of the 
invention referring to the accompanying drawings, it is to be understood 
that various modifications and changes will easily occur to those having 
an ordinary knowledge in the art and the invention can be easily replaced 
by embodiments which satisfy substantially the same objects as those 
described hereinabove and attain substantially the same effects as those 
described hereinabove.