The present invention relates to a system for the automatic release of concrete products, in particular cast concrete products from flexible and deformable dies or moulds.

Normally, the mould-release of cast concrete products, i.e. the extraction of these products, once dried, from the respective flexible and deformable moulds, is carried out manually. The moulds are generally made of rubber or deformable plastic. Hereinafter, for convenience, "rubber mould" will also be used to indicate a generic flexible and/or deformable mould made of other suitable materials.

A type of manual procedure for the mould-release of cast concrete products involves the overturning of the moulds on a conveyor belt, in such a way that the "noble" or shaped surface of the products is facing upwards. Thereafter, the rubber mould, starting from a front edge thereof, is lifted and flexed while keeping the products adhering to the underlying surface. In this way, the products are extracted from the mould, but such a procedure involves a waste of time and, depending on the size of the mould, can also result in the need to have more than one operator available for each mould.

Other manual procedures for the mould-release of cast concrete products do not require the overturning of the mould with the products inside, but carry out the extraction of the products with the "noble" or shaped part facing downwards. Similar procedures reduce the physical burden of the operator, but involve an increase in the time required, and therefore the costs, to carry out each extraction. Moreover, the manual repositioning of the mould in its tray/support is also a labour burden and may lead to a considerable waste of time .

Ultimately, the operation of manual extraction of the cast concrete products from the respective moulds always involves a great cost of labour. In addition, this operation may cause damage to the product, since it is not a controllable operation and mostly depends on the capacity and expertise of the single operators.

Therefore, some machines have been introduced on the market which facilitate the manual extraction of the products, forcing the moulds to flex through rigid mechanisms. This forced flexing, if not properly calibrated, could however "overstress" the rubber or, in general, the material with which the moulds are manufactured. Moreover, the current machines that facilitate the manual extraction of the products do not automatically adapt to the different types and shapes of moulds and product.

Document EP 1935597 Al describes a machine for the mould-release of concrete products according to the preamble of claim 1. This machine comprises a rigid drum, set in rotation to extract the concrete products from flexible dies. However, the dies must necessarily be provided with a portion for the engagement with a hooking tooth provided on the rotating drum of the mould-release machine. It follows that the machine is configured to operate only with moulds having predetermined shape and size (in terms of length and thickness) .

The object of the present invention is therefore to provide a system for the automatic release of concrete products, in particular cast concrete products, from flexible and deformable moulds or dies, that is able to solve the above-mentioned drawbacks of the prior art in an extremely simple, cost-effective and particularly functional manner.

In detail, an object of the present invention is to provide a system that is able to perform the automatic mould-release of cast concrete products from flexible dies using dies of any length and thickness, even if mixed together.

Another object of the present invention is to provide a system that is able to perform the automatic mould-release of cast concrete products from flexible dies in a quick and cost-effective manner.

A further object of the present invention is to provide a system that is able to perform the automatic mould-release of cast concrete products from flexible dies in an efficient and safe manner.

These and other objects according to the present invention are achieved by implementing a system for the automatic release of concrete products, in particular cast concrete products from flexible and deformable dies or moulds as described in claim 1.

Further features of the invention are highlighted in the dependent claims, which are an integral part of the present description.

In general, the system for the automatic release of products made from cast concrete from flexible moulds of the present invention comprises at least a first conveyor belt, configured to move the dies or moulds of resilient material with the dry products therein, whose "noble" or shaped surface is facing downwards. The system then comprises a mould-release machine which receives the dies or moulds from said conveyor belt. The mould-release machine consists of a plurality of apparatuses, typically consisting of movable and rotating brushes, configured to separate each product from the respective mould, as well as to convey each product on at least a second conveyor belt and each mould on a third conveyor belt, respectively.

The second conveyor is configured to convey the products out of the mould-release area, while the third conveyor belt is associated with at least one gripper configured to grip each mould and reposition it on one of the product manufacturing lines, arranged parallel to such a third conveyor belt. The automatic mould- release system is configured in such a way that, at the end of the mould-release process, each extracted product maintains its "noble" or shaped surface facing upwards .

The features and the advantages of a system for the automatic release of concrete products, in particular cast concrete products from flexible and deformable dies or moulds, according to the present invention will become apparent from the following exemplary and non- limiting description, made with reference to the accompanying schematic drawings, in which:

figure 1 is a schematic side elevation view of the main components of a preferred exemplary embodiment of the mould-release system according to the present invention; figures 2A, 2B and 2C show three separate processing steps of the dies or moulds, containing the dried products, using the mould-release system of figure 1, respectively;

figures 3A and 3B show side elevation and cross- section views, respectively, of a further processing step of the dies or moulds, containing the dried products, using the mould-release system of figure 1 ; figures 4A and 4B show two separate processing steps of the dies or moulds, from which the dried products are extracted, using the mould-release system of figure 1, respectively;

figures 5A and 5B show two distinct components of the mould-release group belonging to the mould-release system of figure 1, respectively; and

figure 6 is a schematic top plan view of a preferred exemplary embodiment of the mould-release system according to the present invention, associated to a generic plant for the manufacture of cast concrete products.

With reference to the figures, an exemplary preferred embodiment is shown of the system for the automatic release of products made from cast concrete from flexible moulds according to the present invention. The system is indicated as a whole by the reference numeral 10.

System 10 comprises in the first place an apparatus 12 for supplying the moulds or dies 100 and for the pre-mould-release of products 200 contained within such moulds or dies 100. The supply and pre-mould release apparatus 12 in turn comprises a first conveyor belt 14 associated with a first pre-mould-release group 16, as well as a second conveyor belt 18 associated with a second pre-mould-release group 20. The second conveyor belt 18 is arranged downstream with respect to the first conveyor belt 14 and both pre-mould-release groups 16 and 20 are configured to facilitate the subsequent mould-release of products 200, obtained in the mould-release machine 22 positioned downstream both with respect to the first conveyor belt 14 and with respect to the second conveyor belt 18.

The first conveyor belt 14 and the second conveyor belt 18 convey moulds 100 towards a mould-release group 36 of the mould-release machine 22, described more in detail hereinafter and configured to carry out the extraction of products 200 from the respective moulds 100. Each mould 100, containing one or more products 200 and still allocated in the corresponding tray (not shown) , comes from the "dry line" of the manufacturing plant of products 200 and is transferred onto the first conveyor belt 14 via an overturning machine 650 (see figure 6) , configured to release moulds 100 with products 200 on such a first conveyor belt 14 and return the empty trays to the manufacturing plant of products 200.

At the end portion of the first conveyor belt 14, the mould 100, with products 200 therein, passes through the first pre-mould-release group 16. The first pre-mould-release group 16 consists of a lifting device 24 and of a gripping mechanism 26 properly shaped and operatively connected to such a lifting device 24. In detail, with reference to figures 2A-2C, the lifting device 24 preferably consists of a pneumatic cylinder, while the gripping mechanism 26, when actuated by such a pneumatic cylinder 24, is movable with a reciprocating motion along a substantially vertical direction and orthogonal to the advance direction of the first conveyor belt 14.

Each mould 100 proceeds on the first conveyor belt

14 until its front free edge, with reference to the advance direction of said first belt conveyor 14, is in contact with or in abutment on the gripping mechanism 26. The mould 100 then stops in this abutment position and its front free edge is lifted by the gripping mechanism 26, so as to cause the detachment of the front wall of products 200 from mould 100 itself. The first pre-mould-release group 16 is configured in such a way that, once the pneumatic cylinder 24 has reached the stroke end in the lifting step of the gripping mechanism 26, the gripping mechanism 26 is able to release the front free edge of the mould 100, which returns to abut on the surface of the first conveyor belt 14 (figure 2C) . At this point, the mould 100 resumes its motion and, once the mould 100 itself has integrally surpassed the first conveyor belt 14, being on the second conveyor belt 18, the pneumatic cylinder 24 moves the gripping mechanism 26 downwards waiting for the next mould 100.

Each mould 100 then passes on the second conveyor belt 18, where the second pre-mould-release group 20 is. The second pre-mould-release group 20 consists of one or more projecting or convex portions 28 (figures 3A and 3B) of the surface of the second conveyor belt 18, as well as of at least one shaped roller 30 arranged above the second conveyor belt 18, at the projecting or convex surface portions 28 thereof, and rotating about a shaft 30A. The projecting or convex portions 28 and the shaped roller 30 are configured to jointly cause a first detachment of the lateral walls of the products 200 from the respective lateral walls of the mould 100, thus further facilitating the detachment of each product 200 from the mould 100 itself. At this point the mould 100, after having integrally surpassed the second conveyor belt 18, enters the mould-release machine 22 through a third conveyor belt 32 belonging to the mould-release machine 22 itself.

The third conveyor belt 32 is equipped with lifting means 34 of the front extreme end 44 of the third conveyor belt 32. Preferably, the lifting means 34 consist of a pneumatic cylinder. The mould-release machine 22 is instead provided with a mould-release group 36 operatively connected to the front extreme end 44 of the third conveyor belt 32. When a single mould 100 arrives at the front extreme end 44 of the third conveyor belt 32, which is hinged and controlled by the pneumatic cylinder 34, the pneumatic cylinder 34 lifts the front extreme end 44 of the third conveyor belt 32, thus pressing mould 100 against the mould-release group 36 with a predefined pressure specific to obtain the mould-release by friction of the products 200.

In detail, the mould-release group 36 is provided with a plurality of rollers or brushes 38, 40 and 42 provided with bristles made of a flexible material, such as a polymeric material of various formulas. Brushes 38, 40 and 42 are mounted on respective shafts 38A, 40A and 42A with rotating and mutually parallel axes. Shafts 38A, 40A and 42A are oriented along a direction substantially perpendicular to the development direction of the various conveyor belts 14, 18, 32, 54, 58 and 66. A first brush 38 is fixed to the frame of the mould-release machine 22, so as to have its rotation axis 38A in a well-defined position with respect to the position of the axis of the return drum placed at the front extreme end 44 of the third conveyor belt 32.

The first brush 38 is idle and is configured to rest on the upper surface of each mould 100, so as to rotate following the motion of the back of mould 100 itself in its path at the front extreme end 44 of the third conveyor belt 32. As shown in figure 4A, the front free edge of mould 100 is brought into contact with a second brush 40 (figure 5A) , mounted on a first floating arm 46 actuated by a first moving and lifting system (comprising, for example, a first pneumatic cylinder 48) and set in rotation, at a predetermined speed, by a first motorisation device 50. The first floating arm 46 has the function of adapting the position of the second rotating brush 40 to the various possible sizes and shapes of mould 100. The second rotating brush 40 captures by friction the front free edge of the mould 100 and keeps it lifted and separated from the surface of the products 200.

While the third conveyor belt 32 continues its motion, a chain lifting mechanism 52 (or any other lifting system) connected to the first floating arm 46 at the same time makes the second rotating brush 40 carry out an arc of circumference upwards up to a predetermined position in proximity of a third rotating brush 42. The first floating arm 46 of the second rotating brush 40 is connected, through a pair of connecting rods 56, to a fourth conveyor belt 54 positioned downstream of the third conveyor belt 32. The rear extreme end of the fourth conveyor belt 54 can thus be lifted so that, when it reaches the "high" position at the third rotating brush 42, the fourth conveyor belt 54 is aligned with the third conveyor belt 32, allowing products 200 to pass without problems from the third conveyor belt 32 to the fourth conveyor belt 54 and, therefore, to a fifth conveyor belt 58 configured to transfer such products 200 outside the mould-release machine 22.

The third brush 42 is set in rotation, at a predetermined speed, by a second motorisation device 60 (figure 5B) and is connected to the frame of the mould- release machine 22 via a second floating arm 62. The second floating arm 62 is hinged to the frame of the mould-release machine 22 and its position is adjusted by a second moving and lifting system (comprising, for example, a second pneumatic cylinder 64) . Mould 100 is thus sucked into a cavity formed by the three brushes 38, 40 and 42 when these brushes 38, 40 and 42 are located adjacent to each other (figure 4B) and is forced to flex following the profile of the first idle brush 38. Products 200, instead, being rigid, do not follow the forced flexing of the mould 100 and detach completely from it by following the straight direction imposed by the surface of the third conveyor belt 32, thus going to abut on the subsequent fourth conveyor belt 54.

The mould-released products 200, i.e. extracted from the respective mould 100 and with their "noble" or shaped surface already facing upwards, are moved by the fifth conveyor belt 58 to be transferred outside the mould-release machine 22 in the direction of the quality control and packaging area. In the meantime, the empty mould 200 is pushed by brushes 38, 40 and 42 towards a sixth conveyor belt 66, on which said mould 200 is positioned with its cavities (where products 200 were previously inserted) facing upwards.

Once all of the empty mould 100 has surpassed the mould-release group 36, the second rotating brush 40 returns to its rest position, waiting for the arrival of a new mould 100 to be mould-released. The sixth conveyor belt 66, preferably arranged parallel to the other conveyor belts 14, 18, 32, 54 and 58 and moved in the opposite direction with respect to the moving direction of such conveyor belts 14, 18, 32, 54 and 58, then sends each empty mould 100 up to a predetermined collection point, from which such empty mould 100 is picked and repositioned within its tray on the "dry line" of the manufacturing plant of products 200 ( figure 6 ) .

The system 10 for automatic mould-release of products 200 so far described, using the flexibility of brushes 38, 40 and 42 of the mould-release group 36, the automatic adjustment capabilities of the lifting means 34 of the third conveyor belt 32 and of the moving and lifting systems 48 and 64 of the rotating brushes 40 and 42, as well as the natural flexibility of moulds 100, allows the products 200 to be mould- released without the need of gripping elements for moving and flexing the mould 100 and without the need for the presence of labour. As shown in figure 6, the system 10 for the automatic mould-release of products 200 described so far can be inserted into a both a manual and an automatic plant for the manufacture of cast concrete products. In both cases, the plant for the manufacture of cast concrete products consists of two production lines, i.e. a line on which the fresh products transit and a line on which the dry products transit. The fresh products line consists of a coating area where a layer of paint is applied manually or via an automated system to moulds 100, already sprayed with a detaching agent, which will impart the final colour of the respective "noble" or shaped surface to products 200.

Subsequently, moulds 100 pass through a concrete casting apparatus, where they are filled and vibrated and where the excess material is scraped and removed from the top of each mould 100. These operations can be carried out either manually or through automatic dispensing, vibration and scraping systems. Moulds 100 thus filled are then left to rest in proper curing chambers to allow the concrete to solidify.

Once the concrete has reached the required degree of curing, the moulds 100 pass on the dry products line, where the products 200 are separated from the moulds 100, subjected to quality control and packaged for sale. Moulds 100 are instead cleaned and directed again towards the fresh products line to be subjected to a new production cycle.

If the system 10 according to the present invention is inserted in an automatic plant for the manufacture of cast concrete products, such a system 10 is arranged parallel to the line on which the dry products transit. Normally, the extraction operation of the products 200 from the moulds 100 is carried out manually, but with the system 10 according to the present invention it is possible to carry out this operation in a totally automatic manner.

A typical automatic plant for the manufacture of cast concrete products is described hereinafter and is schematically shown, in one of its possible configurations, in figure 6. The mould 100, made of rubber or deformable plastic, arranged in a dedicated metal/wood tray designed to be self-stacking to prevent the use of crates, enters the line on which the fresh products transit along a conveyor belt 250. Mould 100 then passes on a vibrating belt 300 where a dispensing machine 350 and a scraping machine 400 are provided. As shown in figure 6, the dispensing machine 350 is powered by a machine 450 that allows the transfer of the fresh concrete from the mixer to the filling area of the moulds 100.

The mould 100, once filled, scraped and vibrated, reaches an automatic stacking device 500 that creates a stack formed by a well-defined number of moulds 100 with products 200 just cast therein. At this point, a forklift carries the whole stack towards one or more curing chambers 550 inside which a drying process of products 200 occurs.

Once curing is complete, the forklift picks up the stack of moulds 100 with dry products 200 therein and places it on an automatic destacker 600 which, one by one, conveys the moulds 100 to an overturning machine 650. Such an overturning machine 650 performs a rotation by 180° and unloads each mould 100 with products 200 therein on the mould-release line, while the tray is repositioned on the dry products line waiting for mould 100, emptied of products 200, is arranged back inside it by a repositioning gripper 700.

The mould 100 with the products 200 therein then passes through the system 10 according to the present invention, which conveys the extracted products 200 on the fifth conveyor belt 58 towards the quality control and packaging area, while the mould 100 is arranged back into the tray. Once the mould/tray pair has been reassembled, it travels along the belt 750, with which a lubricating station may be associated, and arrives at a deviating machine 800 which connects the dry products line to the fresh products line. The deviating machine 800 then unloads the tray/mould pair onto the belt 250 and the production cycle can begin again.

It has thus been seen that the system for the automatic mould-release of cast concrete products from flexible moulds according to the present invention achieves the objects outlined above. The system for the automatic release of cast concrete products from flexible moulds of the present invention allows the mould-release of the products from the respective moulds in a totally automatic manner, without the need for labour. The system can work with moulds of various sizes and with even complex product geometries, adjusting itself and without the need for downtime to configure the system itself.

The products are extracted by using the flexibility of the moulds and without the risk of breakage or damage of the products in the mould-release step. The products leaving the system are already with the "noble" or shaped surface facing upwards, thereby facilitating quality control on the product surface and further reducing labour costs and time. Overall, the set of these features allows greatly reducing the labour needed, and thus leads to a considerable decrease in costs and also to a great flexibility of the production process.

The system for the automatic release of cast concrete products from flexible moulds of the present invention thus conceived is susceptible in any case to numerous modifications and variations, all falling within the same inventive concept; moreover, all details can be replaced by technically equivalent elements. In the practice, the materials used as well as shapes and sizes, may be any, according to the technical requirements.

The scope of protection of the invention is therefore defined by the accompanying claims.