US3820216A

US3820216A - Production lines for the manufacture of prefabricated buildings

Info

Publication number: US3820216A
Application number: US00292871A
Authority: US
Inventors: Der Lely C Van; H Nieuwenhoven
Original assignee: Individual
Current assignee: C Van der Lely NV
Priority date: 1972-09-28
Filing date: 1972-09-28
Publication date: 1974-06-28
Anticipated expiration: 1991-06-28

Abstract

A PRODUCTION LINE FOR THE MANUFACTURE OF PREFABRICATED BUILDING HAVING A MANUFACTURING LINE FOR THE CONSTRUCTION OF FLOOR, WALL AND CEILING ELEMENTS WHEREIN METAL FRAMES HAVE CONCRETE MOLDED IN PLACE BETWEEN THEM. THE MATERIALS FOR THE CONCRETE AND A CONCRETE MIXER ARE AT ONE END OF THE MANUFACTURING LINE AND A BUFFER STATION IS AT THE OTHER WHERE THE CONCRETE IS ALLOWED TO HARDEN AND THE COMPONENTS ARE CONNECTED TO FORM THE BUILDING SECTIONS. ADJACENT THE BUFFER STATION AND PERPENDICULAR TO THE MANUFACTURING LINE TO FORM A LSHAPED CONFIGURATION IS AN ASSEMBLY LINE ALONG WHICH TRAVEL SECTIONS WHICH ARE CONNECTED AS THEY WILL BE IN THE FINISHED BUILDING TO RECEIVE WALL AND FLOOR COVERINGS, DOORS, WINDOWS AND OTHER COMPONENTS OF THE FINISHED BUILDING. A GANTRY CRANE OVER THE MANUFACTURING LINE IS CAPABLE OF TRAVELING ABOVE THE INITIAL PART OF THE ASSEMBLY LINE FOR TRANSPORTING SECTIONS THEREON TO ABOVE THE CONCRETE MIXER. A FURTHER LINE WITH A FURTHER CRANE FOR MANUFACTURING THE WALL, FLOOR AND CEILING FRAMES IS PERPENDICULAR TO THE MANUFACTURING LINE AND OPPOSITE AND PARALLEL TO THE ASSEMBLY LINE, AND IT ALSO HAS A GANTRY CRANE CARRIED ON PARALLEL TRACKS SO THAT IT CAN TRAVEL OVER THE FURTHER LINE. OFFICE AND STORAGE FACILITIES ARE LOCATED BETWEEN THE ASSEMBLY LINE AND FURTHER LINE. STORAGE FOR THE MATERIALS FOR THE CONCRETE IS LOCATED NEAR THE CONCRETE MIXER AND A WALL OF THE BUILDING HOUSING THE PRODUCTION LINE.

Description

United States Patent [191 Van Der Lely et al.

[111 3,820,216 [451' June 28, .1974

[ PRODUCTION LINES FOR THE MANUFACTURE OF PREFABRICATED BUILDINGS [76] Inventors: Cornelis Van Der Lely, 7,

Bruschenrain, Zug; Hendricus Jacobus Cornelis Nieuwenhoven, Hirssattelweg, 6340 Baar, both of Switzerland [22] Filed: Sept. 28, 1972 [21] Appl. No.: 292,871

[30] Foreign Application Priority Data Primary Examiner-Thomas H. Eager Attorney, Agent, or Firm-Mason, Mason & Albright ABSTRACT A production line for the manufacture of prefabricated building having a manufacturing line for the construction of floor, wall and ceiling elements wherein metal frames have concrete molded in place between them. The materials for the concrete and a concrete mixer are at one end of the manufacturing line and a buffer station is at the other where the concrete is allowed to harden and the components are connected to form the building sections. Adjacent the buffer station and perpendicular to the manufacturing line to form a L-shaped configuration is an assembly line along which travel sections which are connected as they will be in the finished building to receive wall and floor coverings, doors, windows and other components of the finished building. A gantry crane over the manufacturing line is capable of traveling above the initial part of the assembly line for transporting sections thereon to above the concrete mixer. A further line with a further crane for manufacturing the wall, floor and ceiling frames is perpendicular to the manufacturing line and opposite and parallel to the assembly line, and it also has a gantry crane carried on parallel tracks so that it can travel over the further line. Office and storage facilities are located between the assembly line and further line. Storage for the materials for the concrete is located near the concrete mixer and a wall of the building housing the production line.

30 Claims, 4 Drawing Figures PA'l'ENTEmunzs 1914 SHEET 2 [1F 2 PRODUCTION LINES FOR THE MANUFACTURE OF PREFABRICATED BUILDINGS SUMMARY OF THE INVENTION This invention relates to factory production lines for the manufacture of prefabricated cell-like building sections or room units.

According to one aspect of the invention, there is provided a factory production line for the manufacture of prefabricated cell-like building sections or room units, wherein said production line comprises a manufacturing line for the formation of elements of said sections or units and an assembly line for finishing operations upon the sections or units constituted from said elements, and wherein a buffer station or intermediate store is provided at the delivery end of the manufacturing line for the temporary storage of completed elements, said buffer station or intermediate store adjoining, or being close to, a mounting depot or station at the receiving end of the assembly line.

According to a further aspect of the invention, there is provided a factory production line for the manufacture of prefabricated building sections or room units, wherein said line has two portions and is generally L- shaped in plan view, one of said portions comprising depots or stations for the construction of basic ele ments of said sections or units and the other portion comprising depots or stations for finishing operations on the assembled sections or units.

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

FIG. I is a plan view of the floor of a factory arranged for the manufacture of prefabricated building sections by a method in accordance with the invention,

FIG. 2 is a perspective view, to an enlarged scale, a part of a conveyor line of the factory of FIG. 1,

FIG. 3 is an exploded perspective view illustrating the principal elements of a prefabricated building section manufactured by a method in accordance with the invention, and

FIG. 4 corresponds to FIG. 3 but shows said elements secured to one another to complete the section.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1 of the drawings, a factory floor l is illustrated in plan view, said floor being provided with a production line which is generally L-shaped. The floor 1 has a long section 2 which comprises an assembly line 7 and a short section 3 which accommodates the greater part of a manufacturing line 10, said lines 7 and extending generally at right-angles and optionally being located at different horizontal levels. Various stores and other depots are provided along the two lines 7 and 10 which together constitute the production line of the factory. The short section 3 includes an office 4 having direct access to the floor 1, a canteen and cloakroom 5 and a wash room 6 with toilet facilities.

At one corner of the floor 1 there is a depot or station 35 located at the head of the assembly line 7 in the long section 2 of the floor, said depot or station 35 also 2 being at one end of the manufacturing line 10 and being fitted for the assembly of prefabricated panel elements to form cell-like building sections or room units intended for the construction of prefabricated dwelling or other buildings. The term cell-like building sections or room units is to be interpreted as implying the provision of at least one wall and/or a floor and/or a ceiling. Once assembled, said building sections or room units are conveyed along the assembly line 7 in common and are there provided with wallpaper or other wall coverings, doors, windows and so on as required. Each building section or room unit is composed of a plurality of paneldike elements and normally will basically consist, as shown in FIGS. 3 and 4 of the drawings, of a floor 80,

upright walls

81 and 82 and a ceiling 83. Building sections or room units that are to be used in the uppermost story of a dwelling or other building or in a bungalow or other one-story building, are also provided with a roof layer in addition to the ceiling 83.

The assembly line 7 has four parallel rails 9 which afford lower conveying means of the conveying line of the factory and the building sections or room units that have been connected to one another at the depot or station 35 are moved step-by-step along the rails 9. The panel-like elements that afford the floors, walls and

ceilings

80, 81, 82 and 83 together with roof layers and other parts are constructed along the manufacturing line 10 which line, as previously mentioned, terminates at the depot or station 35 at the head of the assembly line 7, said two lines 7 and 10 thus joining one another at right-angles. A buffer depot or station of the manufacturing line 10 is furnished where that line joins the assembly line 7, said buffer depot or station being intended for the temporary storage of substantially completed panel-like elements that are ready for use in the assembly line 7. To this end, the buffer depot or station comprises two intermediate stores 11 for

walls

81 and 82, an intermediate store 12 for ceilings 83 and an intermediate store 30 for floors 80. The manufacturing line 10 has four sublines l3, l4, l5 and 16, the sublines 13 and 14 serving for the manufacture of the

walls

81 and 82 while the sub-lines l5 and 16 serve for the manufacture of the floors or ceilings and 83 or both.

The walls 81 and 82 (FIGS. 3 and 4) are afforded principally by two

parallel metal beams

84 and 85 at the opposite edges of a concrete filling 86. The sublines 13 and 14 are accordingly provided with moulds shaped to receive the

beams

84 and 85 and it will be noted that, prior to the casting of the concrete fillings 86, reinforcements and pipes or other ducts for electricity, gas, water central heating and so on may be laid inside the moulds so that said reinforcements, pipes and ducts will be substantially concealed from view in the finished buildings of which the

walls

81 and 82 are to form parts. Each floor 80 consists of an oblong frame 87 of metal beams provided with a concrete filling 88. In order to make these floors 80, the sub-line 15 is provided with metallic moulds and the frames 87 are placed on metal plates or other metal sheets of those moulds and the concrete of the filling 88 is subsequently poured into the frames 87. Theceilings 83 are made on the sub-line 16 and each ceiling consists principally of an oblong frame 89 of metal beams which frame is provided with a filling. The fillings maybe inserted into the ceiling frames 89 in the form of prefabricated sheets or they may be fastened to the frames. If

the building section or room unit of whichthe ceiling 83 forms a part is not to be a section or unit of a building story having a roof, then it may be sufficient merely to fasten the ceiling sheets to the frames 89. If, on the other hand, the building sections or room units are to be parts of single story buildings or of the uppermost storys of multilevels buildings, then it is greatly, preferred that the ceilings 83 should be provided with roof layers.

The end of the manufacturing line remote from the depot or station 35 is provided with four reservoirs l8, 19, 20, and 21 and these reservoirs hold cement, sand, gravel and other minor concrete constituents, such as coloring materials, plasticizers and so on, respectively. The materials which have just been mentioned are fed in appropriate proportions to a concrete mixer 17 from the delivery orifice of which concrete is supplied ready for pouring into the moulds of the sublines 13, 14, and 16. The rectangular frames 87 and 89 for the floors 80 and ceilings 83 are constructed on an assembly line 24 which comprises a plurality of jigs 22 andappropriate welding sets. Lengths of beam are cut to size and are then assembled in the jigs 22 and welded together to form the frames 87 and 89. The completed frames 87 and 89 are conveyed from the assembly line 24 to the receiving ends of the sub-lines l5 and 16 by way of a depot or station 23. The depot or station 23 is provided to enable the frames 87 and 89 to be provided with a rust-proofing or other antioxidant composition when this is considered to be necessary. The composition could, for example, be tar or some other bituminous material or paint or a synthetic plastics composition. The assembly line 24 is furnished with an overhead crane 27 that is movable along two spaced

apartrails

25 and 26. The crane 27 includes a transverse gantry or so-called crane crab 28 so that hoisting gear of the crane 27 can be moved to substantially any point lengthwise or laterally of the assembly line 24 by an appropriate combination of the longitudinal movement 29 that is possible along the

rails

25 and 26 and the lateral movement 31 that is possible across the gantry 28.

The lengths of beams from which the frames 87 and 89 are formed are cut to size at a depot or station.32 at one side of the assembly line 24, stores 33 and 34 for the beams and for other materials such as welding rods and the like being provided adjacent the depot or station 32. The crane 27 is employed to move the cut beam sections from the depot or station 32 to the jigs 22 and is also used to move the completed frames 87 and 89 from those jigs through the rust-proofing depot or station 23 to the receiving ends of the sub-lines l5 and 16. The sub-line 16 is equipped with a roller conveyor having two parallel rows of rollers 91 (FIG. 2) carried by upright supports 90. The roller conveyor of the sub-line 16 affords further lower conveying means. The ceiling frames 89 are placed on the roller conveyor and are moved step'by-step towards the intermediate store 12. The frames 89 may be provided at various depots along the length of the sub-line 16 not only with the ceiling sheets but also with members such as struts, roof layers and actual roof structures. Consequently, at the delivery end of the sub-line 16, the ceilings 83 are almost completed.

Stores

36 and 37 flank the sub-line l6 and contain supplies of the ceiling sheets, struts and roofing parts that have just been mentioned. An overhead crane 39 that is movable along rails 38 is mounted above the

stores

36 and 37 and, like the crane 27, includes a transverse gantry or crane crab 40 to enable hoisting gear of the crane 39 to be employed anywhere between the two rails 38 by an appropriate combination of longitudinal and lateral motions. The crane 39 is employed principally for supplying heavy parts from the

stores

36 and 37 to the sub-line l6 and for moving the completed ceilings 83 from that sub-line to the intermediate store 12. A further overhead crane 43 is movable longitudinally of the manufacturing line 10 on rails 42 and laterally of that line with the aid of a transverse gantry or crane crab 44. It will be noted that the rails 42 extend over the mounting depot or station 35 of the assembly line 7 so that the hoisting gear of the crane can be employed to deliver walls, floors and ceilings from the intermediate stores 11, 12 and 30 direct to the mounting depot or station 35. Said walls, floors and ceilings to 83 are assembled at the mounting depot or station 35 to form the building sections or room units. The same crane 43 may be employed to move skips or other containers of liquid concrete from the mixer 17 to the various moulds on the three-sublines l3, l4 and 15. The crane 43 and its rails 42 afford conveying means whose path of possible movement crosses that defined by the four rails 9. It is advantageous to provide ducts beneath the sub-lines l3, l4 and 15 for passing hot air to speed up the setting and hardening of the concrete. The hot air may be supplied from a central heater and blower at the receiving endof the manufacturing line 10 and may serve the additional function of heating the enclosed factory space during cold weather.

The moulds on the three sub-lines l3, l4 and 15 are so disposed that the floors and walls which are produced thereby are already correctly orientated with regard to the positions which they should occupy when they reach the mounting depot or station 35. The floors and walls 80 to 82 remain in their correct dispositions during their temporary lodgment, as will usually be necessary, in the intermediate stores 11 and 30 and can subsequently continue from those temporary stores to the mounting depot or station 35 without needing to be turned or otherwise substantially changed in disposition..The same is true of the ceilings 83 manufactured on the sub-line 16 and transported from that sub-line to the depot or station 35 by way of the intermediate store 12. After being lifted out of their moulds, the

walls

81 and 82 are turned from substantially horizontal to substantially vertical positions which are such that they are correctly orientated-for their final destinations in the building sections or room units. It is advantageous that the floor to ceiling height of the factory in the region of the manufacturing line 10 should be greater than the equivalent height in the region of the assembly line 7 in order to give adequate room for the mounting or assembly of the prefabricated panel elements at the depot or station 35 and to enable the

walls

81 and 82 to be transported without difficulty in vertical dispositions between the delivery end of the line 10 and the receiving end of the line 7. It will be clear from FIG. 1 of the drawings that the assembly line 7 and the manufacturing line 10 have a combined length which considerably exceeds that of the factory floor 1, the latter length being substantially equivalent to the length of the assembly line 7 alone. As previously mentioned, the lines 7 and 10 together form a production line and this production line also includes the subsidiary assem- I bly line 24 for the principal metallic portions of the building sections or room units.

The floors 80,

walls

81 and 82 andceilings 83are joined together to form prefabricated building sections or room units, substantially as illustrated in FIG. 4 of the drawings, at the mounting depot or station 35 by welding the ends of the

beams

84 and 85 to the beams at the comers of the oblong floors and

ceilings

80 and 83. FIG. 1 of the drawings diagrammatically illustrates five juxtaposed building sections or

room units

51, 52, 53, 54 and 55 which sections or units together form at least part of a one-story building such, for example, as a bungalow. Each section or unit has the basic shape of a rectangular parallelepiped and, as previously mentioned, is afforded principally by one floor 80, two

opposite walls

81 and 82 and one ceiling 83 as shown in FIG. 4 of the drawings. This cell-like frame constitutesthe rigid supporting structure of the prefabricated section or unit but may, of course, be provided with internal partition walls and the like, there being facilities for the production of such partition walls and the like on the sub-lines 13 and 14 of the manufacturing line 10. The juxtaposed sections or units 51 to 55 are moved step-bystep along the rails 9 of the assembly line 7 in the direction indicated by an arrow 8 in FIG. 1 of the drawings. Accordingly, the juxtaposed sections or units 51 to 55 arrive successively at depots or

stations

56 and 57 where further parts are added to the sections or units 51 to 55 which sections or units are bolted, clamped or otherwise releasably secured to one another in the same relative positions as they will occupy in the finished bungalow or other building. The further parts which have just been mentioned include, for example, further roofing, doors and windows, interior floor, wall and ceiling coverings such as tiles, carpets, wallpaper, synthetic plastics wall coverings and so on. The necessary supplies for this purpose can be brought from

stores

59, 60 and 61 by an overhead crane movable along rails 58 in substantially the same manner as the previously described

cranes

27, 39 and 43.

Upon reaching a depot or station 62, kitchen equipment and sanitary ware are supplied and installed, the necessary appliances being kept in

component stores

63 and 64 and in a smaller store 69 having direct access to an open region of the floor 1. An overhead hoisting crane 67 is movable along rails 66 over the three

stores

63, 64 and 69 and can move appliances and other heavy items between various points in those stores, as required, with the aid of a laterally movable gantry or crane crab 68 in the same manner'as has previously been described in connection with the other overhead cranes. Further depots or stations along the assembly line 7 are provided with equipment for installing external paintwork and other finishes so that the building sections or room units may be substantially completely finished when the delivery end of the line 7 is reached.

separately transported to storage or erection sites for permanent (in most cases) re-connection to one another in the same dispositions as they has during their temporary interconnection on the assembly line 7. It has been found that manufacturing tolerances are of no great consequence when this method of construction is employed as the final building, or building story, is reerected on its permanent site with its component sections or units in exactly the same relative dispositions as they had while being finished during their movement along the assembly line 7.

The generally L-shaped plan of the production line on the factory floor I has certain advantages. The final depots or stations of the assembly line 7 are located in an area of the factory floor which is well separated from the other working areas so that, consequently, the final operations, and particularly the exterior painting, can be effected with a minimum of disturbance and with a minimum exposure to damage and to air-borne dust and the like while the paint is wet. The relatively perpendicular arrangements of the lengths of the manufacturing line 10 and assembly line 7 is essentially involve a 90 change of direction of motion at the mounting depot or station 35 so that there is no need for specialized equipment for altering the direction of conveyor paths, crane conveyors and the like. The manufacturing line 10 is divided into closely adjacent but separate sub-lines in such a way that the prefabricated panel elements constructed thereon reach the mounting depot or station 35 in generally correct relative dispositions for the assembly of the building sections or room units such as those indicated by the references 51 to 55 in FIG. 1 of the drawings. After the

walls

81 and 82 have been brought to vertical dispositions, they have only to be welded to the floors and ceilings 83. The generally L-shaped disposition of the production line also provides an efficient arrangement of the subsidiary assembly line 24 upon which the frames 87 and 89 and

metal beams

84 and 85 are produced. These essential metal parts are delivered direct to the receiving end of the manufacturing line 10 and all of the components and equipment stores are located internally of the area that is partially bounded by the generally L-shaped production line. This renders all of the various stores readily accessible from a central area of the factory floor 1 so that the construction workers, office staff and other operatives can reach the stores without having long distances to travel. Accordingly, main stores 71 and 72 are located approximately centrally of the factory floor 1 near the office 4 so that they are readily accessible to all the different manufacturing and assembly areas of the production line and so that the office staff can readily check upon the receipt of materials by the stores 71 and 72. Bulk stores for cement, sand, gravel and other such materials are separate from the stores which have so far been mentioned and are preferably located at a readily accessible site close to, but outside, the enclosed space of the factory floor 1. Nevertheless, supplies of such materials for immediate use are contained in the reservoirs 18 to 21 in very close proximity to the concrete mixer 17 at the receiving end of the manufacturing line 10 which comprises the concretereceiving moulds. Thus, the distances between the reservoirs 18 to 21, the concrete mixer 17 and the moulds on the line 10 are all very short. As the assembly line 7 is disposed along the long limb of the generally L- shaped production line, its free end terminates near a relatively empty region of the floor 1 in which region there is sufficient space available for the erection of a demonstration or show house or bungalow 70. The

close to the main entrance to the factory in a region thereof where the noise level will be relatively low so that potential customers and other persons can be received and entertained without undue disturbance.

It will be self-evident that the prefabricated building sections or room units that are produced in accordance with the invention may be used for purposes other than dwelling houses and bungalows. They are equally suitable for the construction of office buildings, schools, hospitals and business premises of many kinds. It is particularly advantageous to construct the walls, floors and/or ceilings of the prefabricated sections or units from concrete and steel beams because the panel elements which those beams and concrete fillings define are very strong without being unduly heavy and have very high resistance to mechanical shocks, such as earth quakes, tending to cause deformations. The modular cell-like construction of the individual building sections or room units allows a bungalow, dwelling house or other building from which they are formed to be finished to a very large extent in the factory before delivery to the erection site. Since the method of manufacture which has been described is a very economic one, the buildings which result therefrom can be made available at a favorable and competitive price. Also because very little finishing work is necessary on the actual building or erection site, a bungalow, dwelling house or other building can be erected in a very short time which may beas little as a few hours.

Although verious features of the prefabricated building sections or room units, and their method of manufacture, that have been described and/or illustrated will be set forth in the following claims as inventive features, it is emphasized that the invention is not necessary limited to those features and that it includes within its scope all of the parts and manufacturing steps that have been described and/or illustrated both individually and in various combinations.

What we claim is:

l. A factory production line for the manufacture of prefabricated cell-like building sections wherein said production line comprises a manufacturing line for the formation of elements of said sections and an assembly line for finishing operations'upon said sections constituted from said elements, and wherein a buffer station is provided at the delivery end of said manufacturing line for the temporary storage of completed elements, said production line also provided with a mounting station with said bufier station being located proximate said mounting station at the receiving end of said assembly line, whereby said elements are connected to one another in said mounting station for constituting said sections.

2. A factory line as claimed in claim 1, wherein said manufacturing line includes a plurality of sub-lines having stations for the contemporaneous manufacture of a plurality of prefabricated metal-edged panel elements, conveying means being provided for transporting said elements to the assembly line.

I 3. A factory line as claimed in claim 2, wherein the manufacturing line is equipped with a plurality of moulds for receiving metal beams and cementitious material for casting said elements.

4. A factory line as claimed in claim 2, wherein a travelling crane is mounted over the manufacturing line, and wherein the path of possible movement of said crane also extends over the buffer station.

5. A factory line as claimed in claim 1, wherein means is provided for heating the manufacturing line from beneath that line.

6. A factory line as claimed in claim ll, wherein the buffer station comprises a plurality of separate stores that are elongated in the general direction of length of the manufacturing line, and wherein the longer sides of said stores extend in substantially the same direction as the greatest dimensions of the elements that are constructed by the manufacturing line, the manufacturing line being arranged in such a way that said elements are conveyed lengthwise to the delivery end of the line and thence similarly to the buffer station.

7. A factory line as claimed in claim 2, wherein said manufacturing line includes sublines and one of said sublines of the manufacturing line is provided with a roller conveyor.

8. A factory line as claimed in claim 2, wherein a travelling crane including a hoisting gear is, arranged near said manufacturing line and at a higher horizontal level than that line, said crane being arranged whereby said hoisting gear thereof is disposed above at least one of said sub-lines and is movable in a direction perpendicular to the travelling direction of the whole crane, the path of possible travel of said crane extending alongside the buffer station.

9. A factory line as claimed in claim 1, wherein the elements formed on the manufacturing line consist partly of concrete, and buffer station has sufficient space whereby it affords a location in which said elements can remain for a period of time sufficient to increase the degree of hardness of the set concrete.

10. A factory production line for the manufacture of prefabricated building sections, wherein said line has two portions and is generally L-shaped in plan view, one of said portions comprising stations for the construction of basic elements of said sections and the other portion comprising stations for finishing operations on the assembled sections.

11. A factory line as claimed in claim 10, wherein the stations of said one portion form part of a manufacturing line while the stations of said other portion form.

part of an assembly line, and wherein the delivery end of said assembly line is located adjacent the free end of one limb of said generally L-shaped production line.

12. A factory line as claimed in claim 10, wherein access points to the production line are located substantially between the limbs of the generally L-shaped configuration.

13. A factory line as claimed in claim 10, wherein component and equipment stores for the manufacture of prefabricated building sections are located substantially between the limbs of said generally L-shaped configuration.

14. A factory line as claimed in claim 10, wherein one limb of the generally L-shaped production line is located at a higher horizontal level than the other limb.

15. A factory line as claimed in claim 1, wherein a concrete mixer and building material stores are arranged adjacent the receiving end of the manufacturing line.

16. A factory line as claimed in claim 10, wherein a buffer station for walls, floors and ceilings affording said basic elements adjoins, a mounting station in which said basic elements are assembled to form prefabricated building sections.

17. A factory line as claimed in claim 13, wherein the delivery end of an assembly line is spaced from other operating stations on the floor of the factory which accommodates the factory line. I

18. A factory line as claimed in claim 16, wherein the basic elements are of oblong configuration, and wherein the manufacturing line occupies the shorter limb of the generally L-shaped configuration and is arranged in such a way that the longer dimensions of said oblong elements are adapted to extend generally parallel to the length of the manufacturing line.

19. A factory line as claimed in claim 1, wherein said line comprises an additional or auxiliary metal assembly line for the manufacture of beams destined to form edges of said elements.

- 20. A factory line as claimed in claim 19, wherein the metal assembly line is arranged to extend substantially parallel to the assembly line for the building sections.

21. A factory line as claimed in claim 20, wherein the metal assembly line and the assembly line for the building sections are both located at the same side of the manufacturingline.

22. A factory line as claimed in 21, wherein the manufacturing line, the building section assembly line and the metal assembly line are arranged in generally chant 10 7 station is arranged at a level above that of the manufacturing line and includes hoisting gear movable transversely across the manufacturing line.

24. A factory line as claimed in claim 10, wherein at least two conveying lines are provided at different horizontal levels.

25. A factory line as claimed in claim 24, wherein a lower conveyor line is afforded by a roller conveyor.

26. A factory line as claimed in claim 24, wherein a lower conveyor line is afforded by rails which cross a conveyor line extending above the manufacturing line.

27. A factory line as claimed in claim 24, wherein the building sections are assembled from basic elements at a location where two conveying lines cross one another.

28. A factory line as claimed in claim 1, wherein the building which houses said line has a greater floor to roof clearance above the manufacturing line than above the assembly line.

29. A factory line as claimed in claim 1, wherein the manufacturing line is equipped with moulds for the formation of panel-like elements, and wherein a crane is movable above said manufacturing line.

30. A factory line as claimed in claim 4, wherein a metal assembly line extends substantially parallel to the building section assembly line, said metal assembly line serving for the formation of the steel beam frames of panel elements to be completed in the manufacturing line, and wherein a travelling crane is provided above the metal assembly line, its path of movement adjoining that of a travelling crane is disposed above the manufacturing line.