US3720493A

US3720493A - Machine for the manufacture of reinforced concrete or prestressed concrete elements

Info

Publication number: US3720493A
Application number: US00056918A
Authority: US
Inventors: M Borcoman; V Ciufu
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-07-25
Filing date: 1970-07-21
Publication date: 1973-03-13
Anticipated expiration: 1990-03-13
Also published as: ES382007A1; NL7011105A; CA934526A; BE752232A; DE2036350A1; CH529620A; FR2060445A5

Abstract

The elements are formed in molds. The machine includes means adapted to displace the molds, in a manufacturing circuit, by rotation, stepwise or continuously, around the horizontal axis, and installations for cleaning the molds, oiling the molds, assembling cores in the molds, concreting, continuous heat treatment of the concrete contained in the molds, demolding and removal of the finished concrete elements arranged outside and in the vicinity of the path followed by the molds and synchronized with the rotation of the molds. The machine is useful for the manufacture of posts, stakes, beams, planks, etc.

Description

wlifitefl States Patent 1 1 Borcoman et al.

1 1March 13, 1973 [54] MACHINE FOR THE MANUFACTURE 2,859,669 11/1958 Leitzel ..18/21 x OF REINFORCED CONCRETE OR 3,477,108 11/1969 Stokes ..425/120 I PRESTRESSED Q R ELEMENTS 3,305,907 2/1967 Baker ..425/99 [75] Inventors: Mircea Borcoman; Virgil Ciufu, FOREIGN PATENTS OR APPLICATIONS both of Paris, France v 234,144 5/1925 Great Br1ta1n ..25/80 [73] Assignee: said Borcoman, by said Ciufu, 75

Paris, France Primary Examiner--J. Spencer Overholser Assistant Examiner-B. D. Tobor [22] Flled' July 1970 Atlorney-Lars0n, Taylor and Hinds [21] Appl. No.: 56,918

57 ABSTRACT Foreign Application Priority Data The elements are formed in molds. The machine in- July 25, 1969 France ..6925511 eludes means adapted displace the molds, in a manufacturing circuit, by rotation, stepwise or con- [52] U.S. Cl ..425/111, 425/435 tinuously, around the horizontal axis, and installations [51] Int. Cl. ..B28b 23/04 for cleaning the molds, oiling the ds, assembling [58] Field of Search ..25/2, 41 R, 41 A-41 F, cores in the molds, concreting, continuous heat treat- 25/41 L, 75, 80, 99, 100; 18/21, 4 P, 4 C, 4 ment of the concrete contained in the molds, demold- R, 4 B, 5 A, 6 E; 425/111, 123 ing and removal of the finished concrete elements arranged outside and in the vicinity of the path followed [56] References Cited by the molds and synchronized with the rotation of the molds. The machine is useful for the manufacture of UNITED STATES PATENTS posts, stakes, beams, planks, etc. 3,360,828 1/1968 Behrens ..18/4 P X 383,174 5/1888 Fuchs Clam, 8 Drawmg Flgures 810,193 1/1906 Daum ..25/75 X A I e W -\b x a m 9 l -5O 1 2 ill/I7 [I I7 Ill/ll PATENTEDMARIGIIQYS I ,720,493

SHEET 1 UF 8 FIG/I.

PATENTEUMH] 31975 SHEET 2 UF 8 mdE PATENTEDHARI 31973 3 720,493

SHEET u 0F 8 USA.

PATENTFUHARIIBIQH 7 3 720 493 SHEET 8UF 3 MACHINE FOR THE MANUFACTURE OF REINFORCED CONCRETE OR PRESTRESSED CONCRETE ELEMENTS The present invention relates to a machine or aggregate for the manufacture of elements of reinforced concrete or of prestressed concrete, as for example: posts, stakes, ribs, beams, small girders, planks, crossbars, slabs, fence parts, etc

Known aggregates for the manufacture of this type of elements are constructed according to the conveyor" method. Such an aggregate constructed in England for the molding of plates of concrete and the like carries the molds in front of the various work stations, by means of chains guided in two superposed horizontal planes. The process of assembling cores, of concreting, of finishing, of heat treatment and of demolding, are effected above and the processes of cleaning and of oiling below the chains. The molds filled with concrete pass through a heat treatment tunnel and arrive in an inclined sector of the chain where the molds are opened and the elements fall onto a removal belt. The aggregate possesses a special installation for placing under tension the cables in continuous movement with bars which can be separated from the chains and be moved parallel to the latter. Another aggregate, constructed in USSR, possesses a conveyor belt formed by the bottom of the molds, which belt is moved also in two superposed horizontal planes, by means of a gearing system with fly-wheels. The concreting is effected in continuous movement by an installation composed of a fixed hopper, of vibrating rollers and of a vibrolevelling plate. The heat treatment of the concrete is carried out with electrical radiators which heat the belt from below, by passing into a tunnel provided with an installation which protects the free surface of the concrete.

These aggregates are of a certain technical value, but have, all the same, a high consumption of mechanical and thermal energy, considerable capital costs and limited possibilities of application especially in the manufacture of the longer elements.

The machine, or aggregate, according to the invention, enables these drawbacks to be avoided and it is characterized by the fact that it comprises means adapted to displace the molds, in a manufacturing cycle, by rotation, stepwise or continuously, around a horizontal axis, and installations for cleaning the molds, oiling the molds, assembly of cores in the molds, concreting, heat treatment of the concrete contained in the molds, demolding and removal of the finished elements of concrete, which installations are distributed outside and in the vicinity of the path followed by the molds, so that the latter pass successively, in the course of their rotation, at right angles to the said installations, the operation of the latter being synchronized with the rotation of the assembly of the molds so that, on each complete rotation of a mold, a complete cycle of manufacture is achieved.

Advantageously, there is provided a rotary support body which transports the molds, mounted on its outer surface, before the work stations, synchronized with the rotation, in continuous or stepwise movement, of the body-mold assembly. Thus, the formation of the elements and their hardening, wholly or partial, is effected with a very much reduced consumption of energy, a substantial economy of structural surface and less handling.

The aggregate may be produced according to several variations of the general technological flow which depend essentially on the sort of rotation of the body and of the place where the processes of heat treatment and of concreting are carried out. In the case where the rotation of the body-mold assembly is effected stepwise, aggregates of type I are used with molds attached on the body around a polygonal contour. These aggregates differ essentially in respect of the place of execution of the concreting: on the body itself or outside the latter. The separation of the concreting outside the body can be shown to be advantageous when the method is applied to the manufacture of heavier elements. In this case, the molds are detachable with respect to the body, assembled in rigid batteries, to facilitate their handling at the concreting station. For the rotation of the body-mold assembly in continuous movement, use is made of aggregates of type II, with molds fixed on the body around a circular contour.

In the following description, two embodiments of the aggregate according to the invention are described, with reference to the accompanying drawings, purely by way of illustrative but non-limiting example.

In the drawings:

FIG. 1 is a transverse section of an aggregate of type I for the manufacture of posts or of stakes of prestressed concrete;

FIG. 2 is a lateral view of the aggregate of type I;

FIG. 3 is a longitudinal section of the concreting installation of the aggregate of type I;

FIG. 4 is a transverse section of an aggregate of type II for the manufacture of small linear elements of reinforced concrete;

FIG. 5 is a lateral view of the aggregate of type II;

FIG. 6 is a perspective view of the concreting installation of the aggregate of type II;

FIG. 7 is a perspective view of the installation for heat treatment of the aggregate of type II; and

FIG. 8, lastly, is a diagram of the demolding installation of the aggregate of type II.

According to the invention, the aggregate comprises a rotary support body which moves the molds 1 through the manufacturing cycle and installations for cleaning the molds N, oiling the molds H, assembly of the cores in the molds A, concreting B, heat treatment of the concrete contained in the molds T, demolding D, removal E of the finished elements of concrete, mounted all around the body and having their operation synchronized with the rotation of the body-mold assembly so that at each rotation of the latter, executed in continuous or stepwise movement, the formation of the elements 2 is obtained, and their total or partial hardening.

The body for supporting and for rotating the molds can be constructed according to several techniques. Its structure must be rigid, capable of supporting the forces which result from its own weight, the weight of the molds and of the concrete as well as the forces transmitted by the various installations. To this end, there is used for the structure of the body welded pipe sections 3, rigidified transversely by rings 4, and longitudinally by sectional members 5. The diameter and the length of the body are selected, as far as possible, of

large dimensions knowing that the production of the aggregate is directly proportional to its dimensions. The support of the body-mold assembly is effected by means of rollers 6, either inside or preferably outside, according to several structural solutions. Thus, for the second aggregate, there are used strengthening rings 4 and an inner beam 7, with 2 feet on the outside 8 (FIGS. 4 and 5) whilst for the majority of aggregates, use is made of two diaphragms or drums 9 arranged, in planes at right angles to the axis of the envelope formed by the rings 3, at the axial ends of the said envelope. The drums are reinforced by gussets l and connected to a tubular beam 11, provided with two collars 12, (FIGS. 1 and 2). The rotation of the body-mold assembly is effected by the usual devices 13, the speed and the meshing force being in all cases particularly reduced, because, on one hand, the rotation is effected on rollers and, on the other hand, the molds are loaded only on the descending portion. When the aggregate is used for the manufacture of heavier elements, the rotation of the body-mold assembly can be effected, in certain cases, only by the eccentric loading of the concrete itself.

The molds are assembled in groups or batteries, by welding by means of transverse and longitudinal metallic sectional members according to several structural solutions. The batteries will be constructed particularly rigidly when they have to sustain forces for the tensioning of the threads or strands. The assembly of the batteries on the rotary body is effected as a function of the type of aggregate. For aggregates of type II, the batteries are fixed on the body, close to one another, around a circular contour, by means of elastic supports. For aggregates of type I, the batteries are mounted on the body, along a polygonal contour, either fixed or movable.

The cleaning and oiling of the molds is done in a zone where they are inclined above the horizontal plane passing through the axis around which the molds turn, to facilitate the flow of the mixtures used. The respective installations are of a special model with jet devices 14, gutters l5, protective hoods 16, air systems 17, and displacement devices 18. In a to-and-fro movement, executed automatically along the molds, the jet devices take up the mixtures from the gutters and direct them under pressure on the molds. The excess of the mixtures employed (water with sand for cleaning and oil for oiling) is recovered in the same gutter. For the aggregate of type II, the gutters are fixed and the rest of the installation movable (FIG. whilst for the aggregate of type I, the whole installation is movable (FIG. 2).

The assembly of the cores is effected differently according as the elements are of reinforced concrete or of prestressed concrete. In the first case, there is generally used the assembly of cores in a skeleton, which can be assembled by conventional means or by containers 20. In the case of the manufacture of elements of prestressed concrete, use is made, according to FIGS. 1 and 2, of a positioning installation and of a tensioning installation of the usual type with a press or jack 21, and a hydraulic pump 22. The installation for positioning the threads or strands 23, of the passive or feed head of the battery or group of molds 24, includes four circuits, one for each mold, provided with spools 25,

movement devices 26, flexible tubes 27, elastic supporting devices 28 and retainingjacks 29, connected to the circuits by elastic means 30, in push-button control manner, the strands unwinding, entering the molds where they are stopped automatically at the active or traction head by means of a time relay mounted in the control system. The arrest of the strands immediately triggers the operation of the jacks which lock them rigidly in respective female cones, by means of keys in three portions. During the positioning and the tensioning, the battery is covered with a protecting screen 31.

The concreting is effected in the upper part, according to the method of rotation of the body-mold assembly. If the rotation is effected continuously, the installation illustrated in FIG. 6 is used, which includes a hopper 32, with a discharging opening which embraces several molds, curved plates 33, having folded back ends 34, vibrators 35, elastic means such as springs 36, sliding parts 37, and a fixing beam 38. The plates 33 are mounted in front of the vertical plane passing through the axis around which the molds rotate, just at the side of the hopper, whilst entering the latter slightly, and pressing above the molds so that, by rotation of the latter, which triggers automatically the operation of the vibrators, the filling, the flattening and the finishing of the concrete are ensured. When the rotation of the body-mold assembly is effected stepwise, the concreting is carried out either outside the body, or on the latter. For the first case, there is used, according to FIG. 3, a movable distributor hopper 39, adapted to be moved in the longitudinal direction of the molds, a vibro-finishing plate, vibrating means 40, and a lowering-raising device for the battery 41. The vibro-finishing plate includes a front pusher end 42, two guide wings for the concrete 43, several vibrators 35 and several springs 36. For the case where the batteries rest on the body at the moment of concreting, where the manufacture of smaller elements is concerned, use is made only of the movable hopper and of the vibrofinishing plate.

Heat treatment of concrete is effected by heating by means of a hot fluid, especially steam, by means of an installation which includes: movable heating chambers 44, a hot fluid distributing device and a device for the protection of the free surface of the concrete to prevent the evaporation of water from the concrete. The movable chambers 44 are formed between the easing 3 of the body and the bottom of the molds l, by their assembly possibly with the aid of several elastic parts. The hot fluid distributing device is formed by a conventional steam system 45, and semi-circular distributors in the form of pipes 46, provided with connecting sleeves 47 and having lateral orifices, which pipes are positioned on roller members 48, in a position fixed on the outside and at the middle, in the longitudinal direction of the body, between the movable chambers (FIG. 7). By the rotation, the chambers arrive facing the distributors where they receive automatically steam over the whole zone provided. In this zone, the free surface of the concrete is protected by a flexible or hinged band 49, which rolls over cylinders 50, driven by its friction with the concrete contained in the molds. The continuous protection of the free surface of the concrete by this band 49 enables a shock thermal treatment to be used. There can also be employed other methods of heating especially: fixed steam chambers, gas or electrical radiators, heating panels, high frequency currents, etc The application of the methods mentioned is facilitated by the fact that the respective heat sources can be mounted in a fixed position in front of which the molds pass always with complete accuracy of speed and of distance.

The demolding of the elements is a function of their shape whether or not provided with transverse release (slope), or longitudinal or both. It is recommended to make use of mold-shells of which the demolding can be effected by forced expulsion. Such an installation is illustrated in FIG. 8 for the aggregate for the manufacture of small elements of reinforced concrete. A longitudinal axle 51, parallel to the longitudinal direction of the molds, is mounted in bearings 52. The axle 51 is provided with claws 53 extending radially towards the molds 1. A jack 54, particularly double-acting pneumatic, is adapted to actuate the longitudinal displacements of the axle 51 so that the claws push the elements and move them a little forward so ensuring their fall. The path of the axle is controlled by the rotation of the body itself, by means of an installation which includes: a system 17 for the supply of the jack 54 with fluid, an electricail system 55, two electrovalves 56, two contactors 57, and two series of cams 58, fixed internally all around the body. At the moment when the elements 2 arrive facing the claws 53, the cams 58 close the contactors 57 and actuate a longitudinal movement of the axle 51 causing the claws 53, to slide between the elements and there molds and so to expel the elements 2 from their molds 1. In the case of the manufacture of elements with a transverse release (slope), the expulsion is effected from the inside by an installation adapted to this purpose. The demolding of prestressed concrete elements is facilitated by the fact that the transfer of force to the concrete ensures, in certain cases, the rupture of adhesion; thus the elements can fall from the molds which, according to the invention, arrive for demolding completely inverted.

The removal of the elements is done by known means: roller belts 59, carriages etc In the case where the heat treatment must be continued outside the body, the removal belt is placed in a heating tunnel 60 (FIG. 4), constructed underground or elevated,

between the aggregate and the depot The removal by I belt can be coupled in certain cases, with an installation for placing in containers.

The installations described are connected to a central control and monitoring panel 61 (FIG. 5). They are mounted on metallic structures 62, which also support the platforms, the ladders and possibly the roofing.

The aggregate according to the invention can be used for the manufacture, with a high economic efficiency, of reinforced and prestressed concrete elements such as: posts, stakes, ribs, beams, small girders, planks, cross-bars, slabs, fence parts, etc Relative to other known methods, it brings:

an increase by 100 to 500 percent of production per unit of surface structure,

an increase, to the same extent, of operational productivity,

reduction to the minimum of the energy necessary for the transportation of the molds in the manufacturing circuit, and

a considerable reduction in capital costs and production costs. We claim:

1. Machine for the manufacture in molds of 5 prestressed reinforced concrete elements, said machine comprising an assembly of molds, advancing means for moving an assembly of the molds on a casing in a manufacturing cycle by rotation through a path around a horizontal axis, and a series of installations which include means for performing successive manufacturing steps distributed externally and close to said path, so that the molds pass in the vicinity of said installations, in combination with means for mounting cores in the molds, said core mounting means comprising a plurality of strand advancing means stoppable automatically at the end where the strands emerge from the molds, and jacks triggered by said stopping, causing the locking of the strands rigidly in position, and synchronizing means for controlling the operation of said installations with the rotation of the assembly of molds so that, on each complete rotation of a mold, a complete manufacturing cycle is achieved.

2. Machine according to claim 1, wherein said advancing means comprise a body formed of said casing which is of polygonal section, rigidified by rings and longitudinal beams which serve also for the guidance of the molds, diaphragms arranged in planes at right angles to the axis of the casing, at the axial ends of the latter, and reinforced by gussets, the body being supported by tubular beams provided with two supporting collars arranged to roll on outer rollers. I 3. Machine according to claim 1, wherein the advancing means includes means for moving the assembly in continuous rotation and one of said installations is a concreting installation which comprises a fixed hopper which embraces several molds, arranged above the assembly in front of the vertical plane passing through the longitudinal axis of the assembly, at least one curved plate mounted tangentially to the molds, and elastic means arranged to apply said plate against the molds so that, by rotation of the assembly, filling of the molds with concrete and flattening and the dressing of the concrete are effected automatically.

4. Machine according to claim ll, wherein the advancing means including means for moving the molds stepwise and one of said installations is a concreting installation which comprises a movable distributor hopper, movable in the longitudinal direction of the molds, coupled with a vibro-finished plate which includes a front thrust end and two guide wings for the concrete, vibrators and elastic pressure means for urging the plate onto the molds.

5. Machine according to claim 1, wherein one of said installations is a thermal treatment installation which is provided with semi-circular distributor pipes, connected by sleeves to pipes leading from a hot fluid supply system, said semi-circular distributors being provided with lateral orifices and positioned on roller members in a position fixed outside and in the middle, in the longitudinal direction, of the assembly, so as to direct the hot fluid automatically towards movable chambers which are formed between the casing of the assembly and the bottom of the molds, in the whole of the zone where said chambers pass opposite the lateral orifices of the semi-circular distributors.

6. Machine according to claim 1, wherein one of said installations is a heat treatment zone, and comprising at least one flexible band arranged to roll, in a closed path, on rollers, said band being driven by friction with concrete contained in the molds so as to insulate the concrete from the exterior, in sealed manner, over the whole of the heat treatment zone, whereby evaporation of water from the concrete is prevented.

7. Machine according to claim 1, wherein one of said installations is a demolding installation which includes a longitudinal axle, mounted in bearings parallel to the longitudinal direction of the molds, and provided with claws extending radially towards the molds, a doulbeacting jack controlling longitudinal movements of the axle, a jack fluid supply system, electro valves controlling the admission and escape of fluid in the jack, an electrical control system for the electro-valves, contractors actuating the electric system and earns fixed internally all around the assembly so that at the moment when the elements arrive facing the claws, the contractors are closed by the cams and actuate a longitudinal movement of the axle and sliding insertion of the claws behind the elements so as to release them from their molds.

8. Machine according to claim 1, wherein one of said installations is a demolding installation which is in the vicinity of the low-point of said path and the molds are presented completely inverted so as to face said demolding installation, whereby gravity facilitates the demolding.

9. Machine according to claim 1, wherein said installations include cleaning and oiling installations which are located, in the direction of rotation of the molds, after the low-point of said path in a zone where the molds are again inverted and turned downward so as to enable the recovery, by gravity, of the cleaning and oiling materials used.

10. Machine according to claim 5, wherein one of said installations is a heat treatment zone, and comprising at least one flexible endless band rolling on cylinders, said band being driven by friction with concrete contained in the molds, and insulating the concrete from the exterior, in sealed manner, over the whole of the heat treatment zone, so that the evaporation of water from the concrete is prevented.

Claims

1. Machine for the manufacture in molds of prestressed reinforced concrete elements, said machine comprising an assembly of molds, advancing means for moving an assembly of the molds on a casing in a manufacturing cycle by rotation through a path around a horizontal axis, and a series of installations which include means for performing successive manufacturing steps distributed externally and close to said path, so that the molds pass in the vicinity of said installations, in combination with means for mounting cores in the molds, said core mounting means comprising a plurality of strand advancing means stoppable automatically at the end where the strands emerge from the molds, and jacks triggered by said stopping, causing the locking of the strands rigidly in position, and synchronizing means for controlling the operation of said installations with the rotation of the assembly of molds so that, on each complete rotation of a mold, a complete manufacturing cycle is achieved.

2. Machine according to claim 1, wherein said advancing means comprise a body formed of said casing which is of polygonal section, rigidified by rings and longitudinal beams which serve also for the guidance of the molds, diaphragms arranged in planes at right angles to the axis of the casing, at the axial ends of the latter, and reinforced by gussets, the body being supported by tubular beams provided with two supporting collars arranged to roll on outer rollers.

3. Machine according to claim 1, wherein the advancing means includes means for moving the assembly in continuous rotation and one of said installations is a concreting installation which comprises a fixed hopper which embraces several molds, arranged above the assembly in front of the vertical plane passing through the longitudinal axis of the assembly, at least one curved plate mounted tangentially to the molds, and elastic means arranged to apply said plate against the molds so that, by rotation of the assembly, filling of the molds with concrete and flattening and the dressing of the concrete are effected automatically.

4. Machine according to claim 1, wherein the advancing means including means for moving the molds stepwise and one of said installations is a concreting installation which comprises a movable distributor hopper, movable in the longitudinal direction of the molds, coupled with a vibro-finished plate which includes a front thrust end and two guide wings for the concrete, vibrators and elastic pressure means for urging the plate onto the molds.

7. Machine according to claim 1, wherein one of said installations is a demolding installation which includes a longitudinal axle, mounted in bearings parallel to the longitudinal direction of the molds, and provided with claws extending radially towards the molds, a doulbe-acting jack controlling longitudinal movements of the axle, a jack fluid supply system, electro valves controlling the admission and escape of fluid in the jack, an electrical control system for the electro-valves, contractors actuating the electric system and cams fixed internally all around the assembly so that at the moment when the elements arrive facing the claws, the contractors are closed by the cams and actuate a longitudinal movement of the axle and sliding insertion of the claws behind the elements so as to release them from their molds.