WO2013053958A1

WO2013053958A1 - Machine for the production of prefabricated prestressed concrete elements by means of extrusion and moulding

Info

Publication number: WO2013053958A1
Application number: PCT/ES2011/070708
Authority: WO
Inventors: Esteban RECOLONS MARSAL
Original assignee: Exclusivas Resimart Ibérica S.L.
Priority date: 2011-10-13
Filing date: 2011-10-13
Publication date: 2013-04-18
Also published as: ES2460841A1; ES2460841B1

Abstract

The invention relates to a machine for the extrusion- and moulding-based production of prefabricated prestressed concrete elements, essentially comprising an active part and a moulding part. The machine is provided with an improved screw-actuating system and the design of the machine comprises independent modules that simplify the maintenance thereof.

Description

MACHINE FOR MANUFACTURE OF PREFABRICATED ELEMENTS CONCRETE PRETENSED BY EXTRUSION AND MOLDING

OBJECT

The object of the present invention is a machine for extrusion manufacturing and molding of precast concrete elements prestressed.

BACKGROUND OF THE INVENTION

Concrete prestressing evolves towards geometries and resistances that can no longer be achieved with conventional methods of manufacturing and need more evolved systems. It is usual to find clearly improved production processes, obsolete and inefficient machinery, as well as staff without proper training. All this leads to a capacity limited production and a narrow range of offer.

Currently, the types of manufacturing known For the preparation of prestressed concrete, there are essentially three:

- Vibro-compression: it is a simple methodology and economical, ideal when high-rise products are not required or with special mechanical characteristics It is versatile to work with different products and simple maintenance. This technology, however, has limitations and disadvantages, such as the limitation in height of the products, the intensive use of water, the limitation in mechanical properties and the Cement utilization in large quantity.

- The sliding formwork ( slip-form ): it allows to manufacture products of greater heights (above 50mm). On the contrary it is a technology that has a very high mechanical and handling complexity, and therefore expensive, which limits its application.

- The extrusion that, both in technological complexity as in cost it is situated in an interesting midpoint between the two technologies previous, being able to manufacture high quality products and resistance.

Currently, formwork technologies Sliding and extrusion share the market of the big manufacturers, with ability to address major investments, being able to elaborate Precast reinforced concrete of higher quality and performance.

The use of extruder machinery for molding Prestressed concrete elements saves a lot of resources. This not only has a positive economic impact, but also implies significant reduction of environmental impact.

The extrusion machinery, as a result of the advantages that this technology presents, is currently the subject of evolution continuous technique to overcome certain inconveniences in terms of Limitation of performance and difficulties of use and maintenance. These limitations and difficulties come essentially from the existence of a plurality of motors and drive mechanisms, as well as a arrangement of components and relative fixings between them that give resulting in laborious manipulation and wasted time in the operations of maintenance, change of molds and the like.

It is therefore necessary to provide a machine Improved extrusion that overcomes these inconveniences.

Said machine is claimed in Claim 1 attached.

SUMMARY OF THE INVENTION

The machine for extrusion and molding manufacturing precast prestressed concrete (hereinafter, 'extruder') of the invention allows to develop a range of different products depending on the End customer needs.

Like other extruders, the machine Extruder of the invention is divided into two fundamental blocks, the part active (upper part) and the mold module (lower part). Same part active can work with different molds to make different products.

The active part essentially comprises the following parts:

Motor module, which includes among others:

Spindle drive system motors helical: it activates the different movements that are required in the spindles responsible for extruding concrete.

Electric winder: the electric winder allows electrically connect the machine to any of the power outlets available, while allowing free movement of it at along the slopes

Hopper: houses the fresh concrete to be shaped, delivering it to the set of spindles for its forming.

Front frame: closes the front of the machine and supports the different motors used for the drives included in the previous parts. The extruder of the invention employs the same set of engines for different products, without having to use for this independent machines.

Back protection: covers the back of the machine, closing the assembly so that adequate protection is guaranteed of the pieces and a good aesthetic finish.

The mold module essentially comprises the following parts:

Turning movement conversion mechanisms provided by the spindle drive system motors helical to the different movements that are required in the spindles responsible for extruding the concrete.

Cable support system: used to support the metal cables for prestressing in their corresponding position

Traction chassis: constitutes the basic support of the machine, and allows its movement along the forming tracks of concrete.

Rear tuner mold: shapes the surfaces exteriors of the precast prestressed concrete element, giving it its definitive geometry and finishes, supporting the extrusion process with additional movements

The function of the extruder machine of the invention it consists of molding a concrete mass through an extrusion process (by helical spindles) and concrete configuration with the desired geometry under a mold responsible for the external morphology of the product to manufacture, usually a concrete beam, as well as a set of molds alveolar that allow to form interior cavities or alveoli in the beam. A hopper located in the center of the extruder houses the mass of concrete, allowing its conduction to the spindle system.

The most important and complex part of the machine is the spindle drive system, as it is responsible for transmitting to the spindles and alveoli the set of movements required to be able to form the concrete that comes from the hopper, located directly on the same. To achieve a correct finish, there are 3 independent movements in the set of spindles and alveoli.

-Rotary movement of the spindles to perform the compression of the material, forcing it to circulate according to the direction of advance linear of the shaped material.

-Angular oscillation of the alveoli: required for facilitate the molding of concrete in the cavities (alveoli) of the beam and that It does not adhere to the socket mold. If said adhesion is not minimized, the Alveoli sheet would drag part of the shaped material, distorting its geometry and producing a surface finished with defects and irregularities To do this, each of the alveoli will oscillate angularly a small angle, in an alternative movement of reduced amplitude but high frequency.

-Set longitudinal oscillation: complements the anterior movement to eliminate adhesion between the alveoli and the concrete and achieve a correct finish. In addition to minimizing problems derived from adhesion, this movement helps to compact the mass of concrete, reducing the presence of pores and fissures. This second movement alternatively, in this case linear in the direction of the spindle axis, it has the same characteristics of reduced amplitude and high frequency as in the case of the anterior angular oscillation.

Spindle rotation, along with oscillation angular of the alveoli, it is operated from the same group of engines, since both occur in parallel axes, so that they will remain mechanically linked '. For its part, the longitudinal oscillation feeds on an engine independent, although located next to the previous ones, since the mechanism is unwraps on a perpendicular axis, which would complicate the system of Transmission of this additional engine does not exist.

These movements are transmitted to the different parts of the machine under simple transmissions, by means of pinions and chains or belts, powered by electric motors. Under the previous movements are achieved, at the same time, a 'polishing' of the surfaces of the piece, which leads to a good finish of the product without need for additional surface finishing processes, as is the case with failure required by a vibro-compression process when looking for a finish External quality

As the extruder spindles extrude the material from the hopper, the machine assembly advances along the track, synchronizing its speed with that of forming the beam, by a wheel drive system driven by an electric motor.

To ensure proper positioning of the prestressed metal cables, a system for the support of the same responsible for ensuring its exact placement at the time the dough of concrete is shaped. This system has a drive for collect the cable supports when placing or removing the machine from the track through which it is moved when the tensioned cable assembly.

The extruder of the invention provides some innovative aspects highlighted in relation to the models of the technique previous:

● Independent modules for the hopper and the front and rear protections of the machinery. This improves maintenance and cleaning by allowing only the parts that require it to be disassembled. A distinction of the extruder machine of the invention is that the hopper is attached to the drive module by means of bolted fasteners, which allows it to be separated from the rest of the machine. This facilitates access to it for cleaning and maintenance if necessary, but at the same time allows it to be removed together with the drive module if this is not required. The fact that the hopper is an independent module is also interesting in order to make modifications in it that can optimize the extrusion process, such as installing a concrete dosing device, water supply, vibrators, etc.

● The tuning mold is an independent module , which can be removed in its entirety by means of a set of collapsible screw joints; The motor arranged on the tuner drives both the sides and the upper part, by means of an eccentric action that converts the continuous rotation of the motor into a linear alternative movement.

● Spindle drive system : In order to simplify the design as much as possible, make the machine cheaper by reducing both the number of elements and their complexity, and facilitating the maximum exchange of molds, so that the mechanical connection between the motors that drive the spindles (located in the active part) and the mechanisms responsible for transmitting the movement (located in the different molds) are as simple as possible, two gearmotors are used directly, which provide the output with the appropriate final speed for the spindles . The use of gearmotors improves reliability, since a single device performs the rotation and movement conversion. The rotation of the gearmotors is transmitted by two main chains to the mold multiplier system so that when a mold change is required, it is enough to exchange these two chains to transmit the movement to the spindles.

● New mechanism in the drive system for the longitudinal movement of the spindles , with a double articulated lever that not only improves accessibility to components subject to wear, but also optimizes friction by reducing the bending generated on the spindle assembly . This is one of the key improvements regarding existing extruder machines.

● Compaction movement : the extruder machine of the invention performs a longitudinal compaction movement of the spindles, consisting of a linear oscillation of the spindle-socket assembly, of high frequency and reduced amplitude. To achieve this movement, a kinematic system has been designed that optimizes the mechanical behavior of the assembly: the movement is generated by an electric motor, which transmits its movement to an axis on which a series of eccentrics (as many as spindles) are housed. By means of a connecting rod, the rotation of the eccentric is transmitted to a main crank, articulated at its midpoint, which in turn transmits it to the spindle pusher by means of a transmission bar.

● Mold leveling system: the mold traction system has a leveling system that allows you to adjust its height to ensure a perfect fit with the work track during machine work. Each of the wheel supports (four in total) has a double adjustable guide, by virtue of two bars attached to the wheels and housed inside two tubes welded to the mold frame.

● Tensioning of spindle geared motors : due to the spindle drive system, the machine has a specific tensioning device, optimized for the function it has to play. Each gearmotor is mounted on a mobile support, housed in a vertical guide that allows its movement in order to tighten the chain. A screw located in the upper part of the support rests on a bridge that rests on the fixed frame of the machine, so that simply by turning said screw, the pressure against the bridge forces the mobile support to move vertically. In this way, the rotation of the screw becomes a vertical movement of the entire support of the reducer, which allows tightening and tensioning of the chain quickly. The system thus conceived is simple, because few elements are required and very robust. In addition, when working directly with a gearmotor, avoiding having to include additional transmission systems to adjust the speed of rotation is avoided.

● Electronic spindle rotation control : the two gearmotors that drive the spindle rotation are controlled by a frequency inverter that allows you to regulate your rotation speed at all times. This has clear advantages, because it simplifies the speed regulation compared to other alternatives such as changing the transmission elements to modify the transmission ratio, when changing the product, the system automatically adopts the proper speed, mechanical components are reduced, with which minimizes costs and problems arising from wear, lubrication, etc., and the degree of control possible. Thus, it can work from 5% to 175% with respect to the nominal speed with absolute precision. A mechanical system would be limited to a reduced number of specific turning speeds.

● Thread guide lifting system: the thread guide system is responsible for properly positioning the prestressing cables. To facilitate the placement of the machine of the invention on the track, the cable supports have a turning movement, so that they can be placed transversely to avoid the cables. Once on the track, their reverse rotation, followed by a lifting movement, allows each cable to be arranged in its corresponding housing. For both movements (turning and lifting) the system has two drive nuts accessible from the outside through two holes in the frame. The rotation occurs through a set of conical pinions connected to both the shaft and each of the thread guide supports. For its part, for the elevation of the system, the assembly has a vertical guide, as well as a bearing that is housed inside two machined parts with a spiral path, each located at one end. With this, by activating a second axis, the rotation of the up and down parts causes the vertical movement of the system, because the bearing is forced to follow the path marked by the spiral, and the only degree of permissible freedom is the vertical

● Independent operation of the sides of the rear mold : these will be directly driven with the motor of said mold, which greatly simplifies the kinematic system of the machine, by mechanically independenting said mold from the rest of the drives present in the extruder.

● Electronic control of the reel : the extruder has an electric cable reel to allow feeding. To operate it, hydraulic motors or electric motors are usually used in conjunction with a mechanical clutch, with the aim of allowing the winder to keep the cable tense regardless of the speed of advance of the machine. The machine of the invention has an electronic torque control, so that the winding speed adjustment is done electronically at all times, which improves the reliability of the machine as there are no mechanical elements susceptible to wear and maintenance.

● Electronic traction control : during the extrusion process, it is necessary to control the speed of advance of the machine to achieve a well finished product. In addition, depending on the type of extruded product and the concrete conditions themselves (higher or lower humidity), the effect of extrusion on the advance of the machine may be different. To automate all of the above in a 'transparent' way for the operator, the extruder uses an electric motor with an electronic speed control. Thus, for each product height, the system adopts a reference feed rate, which must be kept constant regardless of the forces involved in the system, which may oppose the force exerted by the traction, or act on it. sense. To this end, a relative encoder connected to the drive axle has been installed in the machine by means of a set of pulleys and belts, which provides a reading of the actual speed of the machine at all times.

● Improvements to facilitate the handling of machine: a folding transport bar has been arranged that allows to raise the machine with a crane bridge without any additional equipment (for example chains), which means a significant saving of time when placing it on the work tracks. The folding design avoids providing height unnecessary to the machine, something very important due to the restrictions of height that can be presented in certain factories, especially if they have of automated concrete feeding systems. The transport bar It has two possible lifting positions: the first one, to raise only the drive module; for example, to change the mold; the second, to raise the complete machine (the active part together with the mold), for example, to move it to a new work track.

● Improved traction system, which includes a new More solid and reliable mechanism for height adjustment. Such regulation it is necessary when the same machine is to be used for the manufacture of differentiated products, so their functionality and reliability result key elements in the machine.

● The tuner mold protection is screwed to the drive module, and not the mold, as found in other machines. With that, manipulating only the drive module also removes said protection, while maintaining the possibility of removing protection only If so desired.

● Improvement in engine layout: the group The engine of the machine has its engine set optimally for your access. Likewise, the disposition of the elements of transmission to facilitate maintenance and, where appropriate, replace wear components such as chains and sprockets.

● All mentioned unions materialize by means of a quick system of folding threaded bolts, with the exception of hopper, which is fixed with common screws.

● Other advantageous modifications: the whole machine Extruder has been equipped with access doors to access parts machine reviews without the need to disassemble any of the modules, including the hopper that incorporates two side doors that allow observing visually the inside of the hopper, specifically the lower opening that Distribute the concrete over the spindles.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment will be described below. preference of the invention in reference to the accompanying drawings, in the which:

Figure 1 is a schematic representation of the assembly of the extruder machine of the invention;

Figure 2 is a schematic representation of the spindle and socket drive system of the extruder machine of the Figure 1;

Figure 3a is a schematic representation of the drive mechanism for spindle rotation movement;

Figure 3b is a schematic representation of the drive mechanism for angular oscillation movement of the alveoli;

Figure 4 is a front view of the mechanism for angular oscillation of the alveoli of the extruder of the invention;

Figure 5 is a schematic illustration of the system kinematic movement of compaction by longitudinal oscillation of the alveoli of the extruder machine of Figure 1;

Figure 6 is a schematic representation of the lifting system of the thread guide of the extruder machine of Figure 1;

Figure 7 is a schematic representation of the folding transport bar device for machine handling of Figure 1.

DETAILED DESCRIPTION OF AN EMBODIMENT PREFERENTIAL

Figs. 1-7 illustrate a preferred embodiment of The extruder of the invention.

Fig. 1 schematically shows the machine Extruder (1) of the invention and its components. Essentially, the machine (1) It comprises an active part and a molding part.

The active part comprises a driving module that includes, among others, the motors (150, 160) of a system (10) of Helical spindle and socket drive, responsible for extruding the concrete elements and shaping its interior cavities, and a reel electric (30) for power supply to the machine (1) allowing the same time free movement of it along the tracks; also of the drive module, the active part comprises a hopper (40) to receive the fresh concrete and deliver it to a set of spindles for its forming, a front frame (50) that closes the front of the machine (1) and supports the different engines used for drives and a rear protection (60) covering the back of the machine (1), closing the set

The molding part essentially comprises: conversion mechanisms (120, 140, 170, 180) of rotation movement provided by the spindle drive system motors helical (10) to the different movements that are required in the spindles responsible for extruding the concrete. a cable support system (20) used to support the metal cables for prestressing in position corresponding, a traction chassis (70) that constitutes the basic support of the machine (1), and allows its movement along the tracks, and a rear tuner mold (80) that forms the outer surfaces of a concrete beam, giving it its geometry and definitive finishes, supporting the extrusion process with additional movements.

Fig. 2 schematically shows the system (10) of spindle and socket drive, which transmits to spindles (110) and alveoli (130) the set of movements required to be able to conform the concrete that comes from the hopper (40) located directly on said spindles (110).

There are three independent movements in the set of spindles (110) and socket (130):

twist of the helical spindles (110): necessary to effect compression and linear feed of the beam material;

angular oscillation of the alveoli (130) required to facilitate the molding of concrete in the alveolar cavities of the beam and prevent concrete from adhering to the socket mold (130); each of the alveoli (130) will oscillate angularly with a small amplitude, in a movement high frequency alternative;

longitudinal oscillation of the spindle-socket assembly to eliminate adhesion between the alveoli (130) and the concrete, and achieve a suitable compacted and a correct finish; it is also a movement alternatively, in this linear case, in the direction of the spindle axis, with the same characteristics of reduced amplitude and high frequency as in the case of angular oscillation.

The rotation of the spindles (110), together with the angular oscillation of the alveoli (130), will be operated from the same group of engines (150), since both are produced in parallel shafts, so that they will remain 'mechanically linked'. The longitudinal oscillation will feed from an engine independent (160), since the mechanism unfolds in a perpendicular axis to the previous ones, which would complicate the transmission system of not existing This additional engine. For reasons of machine compactness (1) the engine (160) is located next to the engines (150).

Figures 3a and 3b are representations schematics of the drive mechanisms for spindle rotation (110) and angular oscillation of the alveoli (130) of the machine (1). In this preferred embodiment, there is a set of 4 spindles (110) (whose number always matches that of alveolar cavities in the final product), driven in continuous rotation by a set of two motors (150).

In Fig. 3a, the transmission from the engines (150) to the spindles (110) it passes through a box of pinions (152) in which, through a set of transmissions by pinion and chain, rotation will be obtained in 4 output shafts (153) starting from only 2 input shafts (151) connected directly to the motors (150) by chains. The fact of employ two independent motors (150) instead of one responds to the complexity that would entail, in a reduced available space, obtain 4 output rotations from a single input. The 4 output shafts (153) of the pinion box (152) will be connected directly, by chains transmission, to an outer shaft (154) corresponding to each of the 4 spindles to whose axis (154) the extruder spindle (110) is rigidly attached. He shaft (154) for spindle rotation (110) must necessarily be hollow so that can be transmitted (see Fig. 3b) by a coaxial inner rotation axis (159) to the spindle (154) of the spindle (110), regardless of spindle rotation (110), a required angular oscillation movement in the socket (130) that remains located next to the spindle (110).

In Fig. 3b, the transmission from the engines (150) the alveoli (130) is made using the same two engines (150) used to turn the spindles (110), and under the pinion box (152), an additional rotating output shaft (155) will be obtained, whose speed Rotation will be substantially greater than that of spindle rotation (110). This will be played with the number of teeth of the pinions involved in each transmission, achieving the desired multiplication. To convert the turn continuous on the output shaft (155) in an oscillating motion, it will be arranged on it a system of eccentrics (156) and bearings.

Fig. 4 shows a front view of the mechanism for the angular oscillation of the four alveoli (130) of the machine (1) consisting of articulated arms (157) that, attached to the eccentric (156) and thanks to arranged levers (158), they generate the movement of desired angular oscillation.

Note that on the same output axis (155) it they have two opposing eccentrics (156), so that the two arms articulated (157) perform the opposite movement. From there, each socket (130) will be connected by a lever (158) to the corresponding arm (157), so that the movement corresponding to two consecutive cells (130) is the exact opposite. This is so to prevent the concrete that is being conformed 'accompany' the alveoli (130) in their oscillation, which It would cancel out the desired effect, which is to minimize adhesion. Both Extreme configurations of the alveoli (130) remain as seen in the Fig. 4 in which it is observed, through the position of the levers (158), that the odd socket pair (130) is in a different position from the pair of alveoli (130) pairs; in dotted lines the positions are represented opposite of the levers (158) within the angular oscillation movement of each of them, and consequently of its corresponding socket (130).

The mechanical connection from the operating lever (158) to the socket (130) will be realized by a solid shaft (159) that will pass through the interior of the shaft (154) hollow previously used in the Spindle rotation (110). This is necessary because both rotations, despite be concentric, they must obviously be independent

Figure 5 is a schematic illustration of the system kinematic movement of compaction by longitudinal oscillation of the alveoli of the extruder machine of Figure 1; The movement will be powered by an independent motor (160), exclusive for this function, since that the opposite would unnecessarily complicate the mechanics of the whole. The turn of the engine (160) is transmitted in this case by a belt (161), due to the problems derived from working with high speed chains. As that in the previous case, the swing will turn into oscillation by resorting to a eccentric (162) articulated with an auxiliary lever (163), this being the responsible for transmitting the movement to a clamp (165) attached to the assembly spindle-socket through a transmission bar (164) necessary for generate a totally linear movement of said set.

It will be noted that the spindle system constitutes the more complex part of the machine of the invention from a point of view mechanic, more so if we consider the consequences of working with a material such as concrete in terms of friction and wear on items refers.

Figure 6 is a schematic representation of the cable support system (20) of the extruder machine of Figure 1.

The cable support system (20) is in charge to properly position the prestress cables. Throughout the entire process of forming a concrete beam, it is necessary to incorporate a system that positions the set of metal cables for prestressing, so that the concrete mass does not move them in relation to their theoretical position during extrusion. So that these supports do not interfere when available the machine on the track where all the cables are laid, is it is necessary to have a manual drive that removes the supports for a Once the machine is in position, put them back in such a way that they support the cables.

To facilitate the placement of the extruder machine on the track, the cable supports can be subject to movement of rotation, so that they can be placed transversely to avoid cables. Once the machine on the track, the reverse turn of them, followed by a lifting movement, allows to arrange each cable in its housing correspondent.

For both movements (rotation and elevation) the system It has two drive nuts (210, 220 respectively) accessible from the outside through two holes in the frame. The turn occurs by a set of conical pinions connected to both the shaft and each one of the cable support system supports (20). For its part, for the elevation of the system, the set has a vertical guidance, as well as a bearing (240) that is housed inside two machined parts (230) with a spiral path, each located at one end. With that, by driving a second axis, the rotation of the up and down parts (230) causes the vertical movement of the system, because the bearing (240) is visible forced to follow the path marked by the spiral, and the only degree of Admissible freedom is the vertical.

Said drive will consist of a 90º turn followed by a slight lifting movement, which will allow to arrange each cable in the housing arranged for this purpose.

Through a set of gears and intervention of a cam, both movements can be generated from the same drive, in the correct order, which facilitates its handling by the staff responsable. In any case, said drive will be carried out so manual; if we consider that it will be necessary to do it only once to each track formed, resorting to its automation through a motor or similar would result in unnecessary cost to the machine

Figure 7 schematically shows the device folding transport bar for machine handling (1).

To facilitate machine manipulation of the invention, a collapsible transport bar is arranged, which in Figure It is shown with the reference (900) in its down position, which allows to raise the machine with a crane bridge without any additional equipment (for example chains), which means a significant saving of time when placing it on the work tracks. The folding design avoids providing height unnecessary to the machine (1), something very important due to the restrictions of height that may occur in certain factories, especially if They have automated concrete feeding systems.

The transport bar has two possible positions (910, 920) of elevation: a) if it is only desired to raise the drive module, use one of the positions (910). This will be necessary, for example, at the time to change the mold; b) if it is the complete machine (the active part together with the mold) what you want to raise, you will resort to the other possible position (920). Thus, it will be done, for example, when moving the machine (1) to a new track of work.

The use of two different positions allows keep the set level in both cases, without resorting to Several anchor points. Note that the longitudinal position of the center of severity is different depending on whether it is the complete machine or only the upper drive module. The transport bar can be moved to anyone of the two positions easily manipulating the crane bridge. Also, the Guided design, ensures that the chosen position remains locked until the machine is re-deposited on the track, so that the handling safety all the time.

Other briefly described below. machine components (1).

Traction chassis.-The mission of the chassis (70) is support the other functional components of the machine (1) at the same time which allows the movement of the machine (1) along the track. This Movement is necessary for a double reason:

a) during the extrusion process the machine must 'accompany' the output of the shaped product, at the same speed, so that the movement along the entire track allows obtaining a beam take advantage of the total length available; and b) regardless of the process of extrusion, traction should allow the machine to move more speed (of the order of 30 m / min) to allow its positioning without depending of the crane bridge of the ship, which gives it greater autonomy.

The traction drive is carried out by means of a electric motor connected to the network through a drive, which allows regulate the speed value depending on whether a slow speed is desired (during extrusion) or higher (to move the machine along of the clues). Despite its higher cost, it is highly convenient to resort to a drive because the speed corresponding to extrusion could vary depending on the characteristics of the concrete and even the product conformed.

The transmission of movement from the engine to the wheels are made by a set of sprockets and chains, using for this a secondary intermediate axis. This axis is necessary to communicate traction to both wheels without connecting them by a common axle that would interfere with the manufactured product or with tensioning cables arranged on the track. A chain transmits the movement from the motor to said axis, at the same time as two other chains, connected to two pinions at the ends of the shaft, They transmit the movement to each of the two driving wheels. On the chassis the remaining functional components of the machine (1) are arranged using, as a general rule, removable bolted joints, so that each of the assemblies can be isolated from the machine for maintenance work or Repair in a simple and fast way.

The 'modular' configuration of the extruder machine The invention is also advantageous to be able to manufacture different products; from this way it will only be necessary to have different models of those Exclusive modules for each product to be produced, among which is not found the traction chassis.

Rear mold.- The main function of the mold later (80) is to provide the final external geometry to the product, both to its upper and lateral surfaces. To do this, and to achieve a good finish, the different contact surfaces have a movement sliding alternative, achieved by the contest of an engine that transmits its movement through eccentrics. This movement will be similar to that it is obtained in the longitudinal movement of the alveoli (130), and for its achievement will again resort to the conversion of the rotational movement of the motor in an oscillating movement by using eccentrics.

Since the breadth of the movements in play is very low, while the frequency is very high, both parts laterals like the upper one designed to configure a beam will join the rear mold assembly (80) by elastic elements which They will allow the required degree of freedom. The use of elastic elements is very simple to materialize and offers better results than others alternatives, such as articulated joints, susceptible to wear very fast given the high frequency of movements.

Each of the contact faces will move in opposition to the adjacent ones, to facilitate the forming and the absence of adhesion, preventing the concrete mass 'accompanying' the pieces in their glide. Again a belt will be used to carry out the transmission from turning to eccentric, due to the high speeds at play.

Hopper.- Housed in the central part of the machine (1), and coupled by threaded joints, the hopper (40) is responsible for house the fresh concrete that is going to be extruded. The hopper is an element static built by welded plates, equipped with the appropriate geometry to ensure proper sliding of the concrete towards the spindles (110).

Electric winder.- The winding mission electrical (30) is to guarantee the machine's electrical supply (1) allowing at the same time that it can move in relation to a shot of fixed current. If a system of this type is not used, it would be necessary for the power supply accompanies the machine, using for example the crane bridge, which would greatly limit the functional autonomy of the device. For this type of machinery, there are alternatives to the use of a electric winder, as is the case with rechargeable batteries. If of the machine of the invention, given the high powers demanded by the different engines used, it would be necessary to include batteries of one size and excessively high weight, which dismisses this option. The winder (30) It consists of a drum on which a shaft is attached, attached to which a rotating brush system, responsible for receiving the power and transmit it to the machine. Coupled to the shaft by elastic joints includes a new electric motor, necessary to spin the disc in the corresponding direction, as necessary to wind or unwind the cable, depending on the direction of progress. The machine of the invention has a electronic torque control, so that the speed adjustment of the winder is done electronically at all times, which improves the machine reliability as there are no mechanical elements susceptible to wear and maintenance

Front frame.- The front frame (50) It fulfills two fundamental functions: a) structurally, it serves as a support for the motors housed in the front of the machine (1), that is, the motors for extruder traction, for the longitudinal movement of the spindle systems (110) and for the rotation of alveoli (130) and spindles extruders (110); b) constitutes the enclosure of the front part of the machine (1), necessary from an aesthetic point of view and to protect Machine components from dust, dirt and other adverse agents. Too It is important to dampen the noise generated by the engines during the machine operation

The reason for anchoring the motors in the frame (50), instead of doing it in the modules powered by each one of them, it is simple. If two or more products are required different, you can use the same machine, changing in each case the sets of spindles, molds and others. Connecting these again to the different engines, you are able to make a different product no need to 'duplicate' the engines, which are one of the most important components expensive In short, this increases the versatility of the machine (1), avoiding having to use specific individual machines for each product to be manufactured

Again, it is a module fundamentally static, built in this case based on metal tube and other profiles structural. The set will be covered with sheet metal to guarantee the enclosure of the set and improve the aesthetic appearance of the machine. For allow agile access to the mechanical parts located on the front of the machine, as is the case with motors, sprockets, chains or belts, without need to resort to unions that require the use of tools, all the frame (50) is equipped with hinged gates accompanied by gas cylinders for manual operation or other similar systems. With this it is possible quickly access those components that require labor replacement or maintenance In turn, the frame assembly (50) joins using screws to the base of the machine (1), so that when you go to make a change in the spindles and mold, both the frame and the motors that supports can be removed quickly and easily.

Rear protection.- The back of the machine (1) is also adequately protected and covered to improve the set durability. In this case the protection does not fulfill any function structural but exclusively protective, which allows a design lightened up

Again, to avoid disassembling the protection on your integrity are available swing gates or other equivalent systems in the different surfaces, to maximize access to functional components of the rear mold.

Once the invention is sufficiently described, thus as a preferred embodiment thereof, it should only be added that it is possible make changes to the configuration and components of the machine extruder without departing from the scope of the invention as set out in the Claims attached.

Claims

1 . A machine (1) for manufacturing precast reinforced concrete elements by extrusion and molding, comprising:

a driving module that essentially comprises:

motors (150, 160) of a drive system (10) of a set of a plurality of helical spindles (110) and a equal plurality of corresponding alveoli (130), responsible for extruding Precast concrete elements and forming cavities in them interiors;

a cable support system (20) used to support metal cables for prestressing in a suitable position; and a electric winder (30) for power supply to the machine (1) allowing at the same time the free movement of it along some tracks, said reel having an electronic torque control for adjust the speed of rotation of the reel;

a hopper (40) to receive fresh concrete and deliver it to the set of helical spindles (110) and socket (130) for conformed;

a front frame (50) that closes a front part of the machine (1) and supports the motors (150, 160) driving the helical spindles (110) and alveoli (130);

a rear protection (60) that covers a back of the machine (1);

a mold module that essentially comprises: conversion mechanisms (120, 140, 170, 180) of rotation movement provided by the motors (150, 160) of the drive system of helical spindles (10) to the different movements that are required in the spindles responsible for extruding concrete;

a traction chassis (70), which constitutes the basic support of the machine (1) and allows its movement along the tracks of conformed; and a rear tuner mold (80), which forms a geometry and final finishing of the outer surfaces of the concrete element, in which said spindle assembly drive system (10) helical (110) and socket (130) drives a first continuous movement of rotation of a first hollow outer shaft (154) of the helical spindles (110), a second alternate angular oscillation movement of low amplitude and high frequency of a second solid rotation axis (159) of the alveoli (130), internal and coaxial to the shaft (154) of the spindles (110), and a third movement alternate linear longitudinal oscillation joint of each spindle (110) and its corresponding socket (130), said three independent movements being each; wherein said first and second movements are triggered by a common group of several identical engines (150), where the common group of several identical motors (150) is controlled by a frequency inverter which allows to regulate its rotation speed, and drives a pinion box (152) whereby, by means of a set of transmissions by pinion and chain, it obtains rotation in several output shafts (153), the number of said being output shafts (153) equal to the number of spindles (110), and on an output shaft additional (155); where the output shafts (153) of the pinion box (152) they are connected by transmission chains to an outer shaft (154) corresponding to each of the spindles (110), each of said axes (154) being rigidly attached to its corresponding extruder spindle (110);

where the additional output shaft (155) of the box sprockets (152) is connected by transmission chains, some eccentric (156), articulated arms (157) and levers (158) about solid rotation shafts (159) internal to, and, coaxial with shafts (154) of the spindles (110) to convert, regardless of spindle rotation (110), the continuous rotation of the additional output shaft (155) in one movement oscillating angle of the inner rotation shafts (159) that are independent of the spindles (110) and each of said axes (159) being rigidly attached to a corresponding socket (130); in which said third Alternative joint linear oscillation movement of each spindle (110) and its corresponding socket (130) is driven by an independent motor (160) whose turn is transmitted by a belt (161) and is transformed into oscillation linear length by means of an eccentric (162) articulated with a lever auxiliary (163) which, by means of a transmission bar (164) transmits the longitudinal movement to a clamp (165) attached to the assembly spindle-socket.

2. The machine of claim 1 wherein on the same output shaft (155) two opposing eccentrics (156) are arranged, each connected to an articulated arm (157), which cause the articulated arms (157) and therefore the levers (158) attached to them perform opposite movements, so that certain levers (158) attached to corresponding alveoli (130) will cause angular movement of said alveoli in a certain direction of rotation, and certain other levers ( 158) together with other corresponding cells (130) will cause angular movement of said cells in the opposite direction of rotation.

3 . The machine of claim 1 wherein the cable support system (20) which allows to make rotation and lifting movements of said supports comprises two drive nuts (210, 220 respectively) accessible from the outside of the machine (1) , a first nut (210) driving the rotation of the supports by a set of conical pinions, and a second nut (220) driving the elevation of the system (20) by means of a bearing (240) guided vertically inside two machined parts (230) with a spiral path.

4 . The machine of claim 1 wherein the rear tuning mold (80), the hopper (40) and the rear protection (60) are modules independent of the rest of the machine (1)

5 . The machine of claim 1 further comprising an electronic traction control of the machine, which automatically adjusts the speed of the same according to the needs of the extrusion process by using an encoder and a frequency inverter, which makes it possible to use the same set of motors of the different drives to manufacture different products.