Plant For Manufacturing Reinforced Concrete Elements, Preferably In The Shape Of A Case

Abstract

A plant for manufacturing reinforced concrete elements in the shape of a case, having working stations connected by conveyors and which working stations mold an open top box, form a lid strip for said box and include concrete pouring stations, concrete vibrating stations, mould moving and lifting station, lid strip smoothing station and a station for cutting said lid strip into individual strips.

Description

The present invention relates to plants and devices for manufacturing reinforced concrete elements preferably for building purposes and in the shape of a case.

The object of the invention is to provide a manufacturing plant for said purpose which is highly automatic in its function thereby decreasing the purpose of manual work and consequently also lowering the manufacturing costs by a higher and more uniform quality of the product.

In the following an embodiment of the invention is described. The embodiment is shown on the accompanying drawings on which FIGS. 1 - 9 show production means of an underpart shaped as an open box to the building element. FIG. 1 is a view from above of a frame provided for stretching of reinforcing irons extending through a concrete mould placed within the frame; FIG. 2 shows an alternative embodiment of the inner wall of the mould in FIG. 1; FIG. 3 shows a vertical transversal section through the mould and the frame along the line III--III in FIG. 1; FIG. 4 shows a vertical transversal section through a framing of joists built up of elements of the kind which is produced in the plant according to the invention; FIG. 5 shows a filling apparatus for the concrete in a vertical transversal section and FIG. 6 shows the same apparatus in a vertical longitudinal section; FIG. 7 shows vibrating means for concrete in the mould in a side elevational view with the mould shown in a transversal section; FIG. 8 shows moving and lifting means for the parts of the mould in a side elevational view with the mould shown in a transversal vertical section; FIG. 9 shows the same moving and lifting means seen in an elevation in right angle to the elevation in FIG. 8; and FIG. 10 shows an apparatus for production of lids to the under parts of the building elements for which the production means shown in FIGS. 1 - 9 are intended; FIG. 11 shows cutting means intended for production of said lids.

The building elements produced in the plant according to the invention have the shape of elongated cases with a bottom 1 (FIG. 4), four walls 2, framing the bottom 1 and a lid 3. Consequently each element is a hollow rectangular body. The bottom 1 and the walls 2 are cast in concrete in one piece, while the lid 3 is cast separately and mounted on the underpart 1, 2. The concrete is reinforced by means of reinforcing irons in the bottom 1 and the lid 3 in the form of nets 4 and in the walls 2 in the form of stretched bars or wires 5 at the bottom and unstretched bars 6 at the top.

In mounted position the elements 1, 2, 3 are placed side by side extending between the walls of a building whereby the lids are forming a floor or the roof of the building and the bottoms a ceiling in the building. Preferably, the elements 1, 2, 3 are provided with a layer of heat and sound isolating material 7. The lid 3 is resting on the walls 2 by means of a vibration absorbing pad 8 for example rubber strip and preferably attached to the walls by means of glueing. The elements are connected to each other by means of concrete poured in recesses 9, 10 formed between each adjacent pairs of element.

The mould for the cast of the lower part 1, 2 of the elements is shown from above in FIG. 1. According to this figure the mold 11 shows outer walls 12, inner walls 13, outer gables 14 and inner gables 15. During the production of a concrete element the mould 11 is placed in a frame 16 with sides 17 and gables 18. The frame 16 is intended to take up the force from the prestretched reinforcing bars 5.

As is evident from FIG. 3 which is a section along the line III--III in FIG. 1 the outer walls 12 of the mould are supporting on the sides 17 of the frame by means of levers 19 provided with a roll 20. The shaft 21 is turnable by means of a lever 30. The levers 19 are pivotable around the shaft 21 in the wall 12. Furthermore the walls 12 and 13 are supported by means of rods 22 which also work as supporting means for the outer gable 14. The inner gable 15 is foldable around a shaft 23 and is fixable to the outer gable 14 by means of a rod 24. There are also pivoting means on the inner walls 13 for the inner gable 15.

In FIG. 2 another embodiment of the mould is shown. According to this figure the mould consists of four L-shaped pieces 27 which are connected by means of double acting power cylinders 28 and 29, for example pneumatic cylinders. By this arrangement it is possible to adapt the size of the mould in a certain range and also to draw the mouldwall together when it has been removed from the cast and hardened piece. This inner frame 27, 28, 29 of the mould is intended to be used together with an outer wall of the mould according to FIG. 1

The gables 18 on the frame 16 are provided with locking means 31 for the reinforcing bars. This locking means 31 are so arranged that when the bars are stretched they will freely move in the locking means 31 outward, but not inwards. Consequently they will keep their stretched state even after the removal of the stretching power. As shown in FIG. 3 the frame 16 and the mould 11 are resting on a plate 32 forming the bottom of the mould.

In FIGS. 5 and 6 the filling apparatus for the concrete mass is shown. In these figures the mould 11, the frame 16 and the bottom plate 32 are shown. The plate 32 is resting on a conveyor 33 with roll members 34. In the position where the filling takes place the conveyor is provided with vibrators 35. The filling apparatus is carried over the conveyor 33 on two rails 36 by means of wheels 37. In the wheels 37 a concrete container is hanging at its bottom part provided with feeding means for the concrete. There are four feeding devices provided; two devices 39, 40 for feeding the concrete mass to the side channels of the mould where the sidewalls 2 (FIG. 4) of the element is formed, one device 41 for feeding of concrete mass to the central part of the mould 11 which concrete will form the bottom of the element and one device 42 for filling the end channels of the mould in which the concrete is forming the short sides of the element.

Each feeding device 39 - 42 shows power driven feeding rolls 43, 44, 45 respectively which each are placed in an opening connected to a hopper shaped part of the container bottom. Underneath the rolls 43 are narrowing channels 46 provided to direct the concrete mass to the side channels of the mould 11. Underneath the feeding roll 44 there is placed a pit 47 formed by two telescopic connected parts of which the underpart can be drawn up around the upper part by means of two power cylinders 48. In the bottom of the underpart two shutters 49 are arranged maneuverably by means of power cylinders between an open and a closed position, the latter shown in FIG. 6. Beneath the roll 45 of the filling device 42 a shovel 50 is pivotably attached to the shaft 51. A control device is arranged to rotate the roll 45 while the shovel 50 is held in its upper position (indicated with dashed and double dotted lines) and then when the desired amount of concrete mass is filled in the shovel to stop the roll 45 and pivot the shovel to its lower position (indicated with continuous lines) whereby the concrete mass is poured into the end channel of the mould 11 in which one of the gables of the element is formed.

In each of the hoppers in the bottom of the concrete mass container 38 there is a kind of mass stream regulating valve, a screw regulated shutter 52 arranged.

The control device comprises a tactile organ 53 (FIG. 6) which indicates when the shovel 50 is in position with its outlet opening over said channel in the mould 11. A second tactile organ 54 is arranged to activate the power cylinder 48.

The vibrating means in FIG. 7 comprises a frame 55 stretching over the conveyor 33 and consequently also over the mould arrangement 11, 16, 32 transported on the conveyor 33. The frame 55 carries by means of a lifting arrangement, for example a hydraulic cylinder 56 the vibrating device 57. The vibrating device 57 comprises a support 58 on the overside of which vibrators 59 are mounted and on the underside of which depressing organs 60 for the mould 11, 61 for the concrete mass in the side channels of the mould and 62 for the concrete mass in the centre of the mould 11 are mounted. The depressing organ 62 comprises a plate 63, vibrators 64 and straightening rolls 65.

Equal to the vibrating means in FIG. 7 the removal means for the mould according to FIGS. 8, 9 are carried by a frame (not shown) by means of a lifting device 66 (only partly shown). The removing means comprises a support 67 by means of power cylinders 68, 69 carrying two gable arrangements 70 and 71 respectively attachable to the outer wall 12 and the inner wall 13 of the mould 11 respectively. In right angle to the gables 70, 71 the support 67 carries an arm 72. To the arm 72 is attached a lifting arrangement 73 by means of which a hook 74 can be drawn in two directions (indicated at dashed - double dotted and continuous lines). The hook 74 is intended to be hooked to latches 75 on the inner and outer gables of the mould 11 (see also FIG. 1).

According to FIG. 10 the lid 3 (see FIG. 4) of the building element will be produced in a separate line including a conveyor 76 on which mould plates 77 will be forwarded. Together with the plates 77 and iron net 78 for reinforcing of the concrete product is forwarded thereby drawn out from a roll 79. Over the track of the plates 77 is arranged a box 80 above which a hopper 81 for the concrete mass is ending. The hopper 81 is provided with a feeding rool 82 and a stream regulating shutter 83. The hopper 81 is carried by means of springs 84 and it will consequently change its position upwards and downwards according to the amount of concrete mass in the hopper. By means of this arrangement an control organ 85 is provided to start a conveyor 86 for concrete mass when the high position of the hopper 81 indicates that the amount of concrete mass in the latter decreas to a predetermined level.

The box 80 is provided with strippers 87 which are placed to allow the concrete mass in the box 80 poured in the same from the hopper 81 to flow out together with the forwarded plates 77 to a predetermined thickness.

Behind the box is placed a stand 88 for a vibrating roll 89 and a frame (not shown) carrying a surface smoothing apparatus 90 comprising a disc 91 rotated by means of an electric motor 92. Sidewards to the conveyor are placed ledges shaped to form the recesses 10 (FIG. 4) at the edges of the produced lid.

As is evident from FIG. 10 the lids are produced as a continuous piece. Consequently this piece has to be cut at distances equal to the desired length of the lids. In FIG. 11 a cutting apparatus is shown. The frame for this apparatus has the form of a box 95 equipped with ventilating means and slideable along the path of the conveyor 96 for the cast piece of concrete. In the box a grinding disc 97 with a driving device 98 is carried by means of slides and moveable by means of the power cylinders 99, 100. Thereby the disc 97 the plane of which is perpendicular to the plane of the cast piece on the conveyor 96 is displaceable in a path in right angle to the edges of the piece which has to be cut and also up and down by means of the cylinders 100. The box 95 furthermore carries a measure device 101 comprising rolls in engagements with the plates 77, thereby measuring the distance which the same are forwarded on the conveyor 96. The box 95 also carries a clamping device 102 with jaws and power means which can bring the jaws to engage with one of the plates 77.

At the side of the conveyor 96 there is attached a buffer device 103 engaging with the box 95.

Besides the now described arrangement the plant includes a station for producing the concrete mass, further transporting means, tunnels or chambers for hardening of the concrete, a mounting station in which the lids are attached to the underpart of the elements.

The production of an underpart of the building element begins with assembling of the mould 11 (FIG. 1) to the in FIGS. 1, 3 shown condition. As mentioned before the innerpart 13, 15 of the mould 11 alternatively can be replaced by the inner part shown in FIG. 2. In connection with the assembling the mould 16 is placed within the frame 16 and at the same time the reinforcing net is placed at the bottom a certain distance over the plate 32. Thereafter the reinforcing iron 5 are drawn through the mould 11 and out through the locking means 31 of the frame 16. Thereafter the irons 5 have to be stretched by means of suitable power means by which operation they are locked automatically in the locking means 31 in stretched condition. Hereafter the not pre-stretched reinforcing irons 6 (FIG. 4) are hanged up in the sidechannels of the mould.

The plate 32 with the mould 11 and the frame 16 is now forwarded on the conveyor 33 (FIGS. 5, 6) to the position for the filling apparatus. While the latter is moved over the mould on the rails 36 the tactile organ 53 will first meet the gable of the mould (placed to the left in FIG. 6, now shown) whereby the shovel 50 is tipped to its lower position and pours its contents in the first end channel of the mould 11. When the gable of the mould has passed the filling apparatus which occurs with the underpart of the pit 47 in its upper position and with the shutters 49 closed said underpart is lowered activated by the tactile organ 54 when it has passed the gable. At the same moment the shutters 49 are opened and the roll 44 is started as well as the rolls 43. Concrete mass is now poured in the side channels of the mould and on the plate 32. However, the layer on said plate will not be thicker than the lowermost edges of the pit 47 allows and the remaining amount of concrete will stay in the box 41.

In the meantime the shovel 50 is raised and filled again by means of the roll 45 and when the tactile organ 53 reaches the second gable the shovel 50 is tipped and pours its contents in the endchannel of the mould 11.

When the pit 47 has reached the second gable the filling apparatus is returned and when the tactile organ 54 reaches the first gable the shutters 49 are closed and the underpart of the pit 47 is raised. Thereafter the mould is free to move on the conveyor to the next station in the production line. The next station is the vibrating station in FIG. 7. When the mould device 11, 16, 32 is forwarded on the conveyor 33 to this station, the vibrating means 57 are lowered by means of the lifting means 56. In lowered position the depressing organs 60 rest on the wall of the mould 11 and hold the same pressed down towards the plate 32 under the vibrating operation which occurs by means of the depressing organs 61 and 63 vibrating the concrete mass in the channels and at the bottom of the mould 11 respectively. The vibration is completed by certain press power while the organs 61, 63 are pressed downwards by the hydraulic lifting means 56. This combined vibrating and pressing operation will result in a very tight and hard concrete with high tensile strength.

After the vibrating and pressing the mould is forwarded on the conveyor 33 to said hardening station where the concrete is hardened in a steam chamber, preferable in the form of a tunnel through which the mould is passing under a certain time.

After the hardening the mould can be removed. Thereby the removing and lifting means according to FIG. 8 is lowered in contact with the inner and the outer walls of the mould 11 and attached to the same. In this position the gable 70 consequently is attached to the outer walls 12 and the gable 69 to the inner walls 13. The shafts 21 (FIG. 3) then are turned by means of the level 30 whereby the levels are pivoted upwards and the rolls 20 loose their contact with the frame wall 17. After removal of the locking means, named in the description of the mould, the outer gable of the mould 11 then can be drawn outwards and removed by means of the means showed in FIG. 9 with the hook 74 attached to the latch 75. Thereafter the outer walls 12 of the mould are free to be drawn outwards through widening of the gable 70 by means of the power cylinder 68.

The next step is to fold the inner gable 15, (FIG. 1) by attaching the hook 74 to its latch 75 after that the removal means in FIG. 1 has been adapted to this operation. Simultaneously with the folding of the gable 15 the sidewalls 13 of the mould have to be drawn inwards and brought out of the contact with the cast building element. At that operation the branches of the gable 71 are drawn together by means of the power cylinder 69.

Now the sidewalls 12, 13 of the mould 11 are free from the extending parts of the cast piece and can be lifted by raising the gables 70, 71 with the lifting means 66.

To make the cast piece free from the frame 16 the prestretched reinforcing irons have to be cut. At this, the power necessary to hold the irons stretched has to be carried out through the binding between the iron and the concrete. Consequently, the removing of the cast piece from the stretching frame 16 must wait until this binding has strength enough to keep the irons stretched. According to this circumstance, the removing can be carried out immediately after the hardening operation mentioned or in order to attain longer binding time the removal operation can be put off till the building element is assembled.

Consequently, the assembling operation can be carried out with the underpart 1, 2 (FIG. 4) of the element separate or still placed within the frame 16. Independent of this the assembling operation begins with placing the isolating material 7 (FIG. 4) in the underpart 1, 2. Thereafter stripes of glue are placed on the upper edge of the walls 2 and around the underside of the lid 3. After that the rubber strip 8 is placed on the top of the underpart 1, 2, the lid is laid down thereon. The building element is now assembled and the underpart 1, 2 and the lid 3 stick together by means of said glue. Preferably, the lifting of the lids 3 is carried out by means of suction organs, attached to the smooth overside of the lid.

Before the arriving of the lids to the assembly station they have been produced simultaneously with the production of the underparts of the building elements in the described separate production line. According to FIG. 10 the first step in the production of the lids is forwarding of mould plates 77 on the conveyor 94. Together with the plates the reinforcement iron net 78 is drawn out from the roll 79 through the box 80.

To the box 80 a continuous stream of concrete mass is delivered by means of the roll 82 from the container 81 which in turn is automatically filled from the conveyor 86 by means of the control device 85 as described. When the plates 77 together with the net 78 are passing through the box 80 they will bring concrete mass out from the box. The layer on the plates will, however, not be thicker than the strippers 87 of the box 80 allows and the rest of the concrete will stay in the box.

After the escape from the box 80 the concrete layer is vibrated by means of the roll 89 and gets a smooth surface by means of the rotating disc 91 in the smoothing device 90. The edges will be formed with the recesses 10 (FIG. 4) by the ledges 93.

After hardening of the concrete to a certain degree in a chamber as described in the connection with the production of the underparts of the building elements, the cast continuous piece on the plates 77 has to be cut to pieces of predetermined length. This operation takes place in the cutting station according to FIG. 11. The continuous piece is forwarded to the station according to FIG. 11. The continuous piece is forwarded to the station on the plates 77 by means of the conveyor 96. When not in operation the slideable box 95 with the cutting apparatus rests on the buffer device 103 in its right end position.

When the plates 77 are forwarded they drive the rolls in the measure device 101. When the predetermined length is indicated the measure device 101 activates the clamping device 102 whereby the jaws engage with the plate 77 between them. As the clamping device 102 is attached to the box 95 the latter begins to slide with the same speed as the plates 77 on the conveyor 96. Simultaneously the power cylinders 100 move the cutting disc 98 downwards through the cast piece presented to the disc whereupon the disc is moved by the power cylinder 99 in transversal direction to the cast piece. As the movement of the box and consequently also the disc 97 is synchronized to the movement of the piece resting on the plates 77 the described operation results in a straight cut over the piece. When the cutting operation is completed the disc 97 again is raised, the clamping device 102 is inactivated and the buffer device 103 which under the cutting operation was subjected to the movement of the box 95 now presses the same back to its right end position.

From the cutting station the cast pieces are delivered in the form of lids of predetermined length to the assembly station.

In the foregoing the plant according to the invention is described in connection with the manufacturing of building elements in the shape of a case comprising an underpart and a lid. However, the plant is adaptable also for other objects of concrete. In the first place concrete elements in elongated shape and reinforced by means of prestretched irons are suitable to be manufactured in the plant. For every product which includes prestretched reinforcing irons and is cast in a production line the use of the described rigid frame provided to hold the prestretched irons and following the mould will be very advantageous. As an example, poles are to be mentioned.

Also the method to form the lids is useable in other objects. In the first hand elongated, flat objects.

Claims

What we claim is:

1. In a plant for manufacturing elongated, reinforced concrete elements for framing of joists in buildings and in the shape of an open box, a casting station comprising a mould including a bottom plate, an outer wall in contact with said bottom plate, an inner wall spaced from said bottom plate, carrying means provided on both said walls for allowing the walls to be removed from the cast piece, said inner and outer walls positioned relative to each other so as to for side channels and end channels stretching along the side of a rectangle, and a rigid frame capable of locking and holding in stretched position reinforcing irons extending through said mold and intended to be prestretched before the casting and an apparatus for the filling of a concrete mass in said mold including a concrete container movable relative to said mold in the direction of said side channels, two concrete feeding devices with feeding openings located, so that they can move over said side channel, one feeding device with a feeding opening stretching between said side channel and one feeding device including a pit provided with a means for raising and lowering it between a position above the inner walls and a position in between the inner walls of said mold and having a bottom opening with edges in the lowered position of the pit a determined distance from said bottom plate, a shutter in said pit provided to close the bottom opening of said pit and remove the concrete mass above the level of said edges.

2. Plant according to claim 1, further including a vibration apparatus which comprises contact means provided with surface intended to be brought in contact with the concrete mass in the different sections of mold, vibrations means for vibrating said surface and power means of pressing the concrete mass by means of said surfaces.