WO2015181691A1

WO2015181691A1 - Thermostatically controlled cylinder for heat treatments, method for making said cylinder and system comprising said cylinder

Info

Publication number: WO2015181691A1
Application number: PCT/IB2015/053771
Authority: WO
Inventors: Enrico Elia Costantino FACCIN
Original assignee: Cos.T.A. S.R.L.
Priority date: 2014-05-26
Filing date: 2015-05-22
Publication date: 2015-12-03

Abstract

The invention is a thermostatically controlled cylinder (1) for heat treating products (PL), preferably plate-like products (PL), comprising an inner cylinder (4) and an outer cylinder (3), wherein between the internal surface (5) of the outer cylinder (3) and the external surface (6) of the inner cylinder (4) a hollow space (7) is defined which is sealed and suited to receive a thermal fluid (FT) intended to heat and/or cool the outer cylinder (3), the hollow space (7) comprising guide means (20, 21; 21') suited to convey the thermal fluid (FT) along at least one path (P1, P2, P3, P4; P1')- Said guide means (20, 21; 20', 21') comprise at least one dilatable element (21; 21') suited to assume at least one operating configuration, in which it is dilated and arranged in contact with the internal surface (5) of the outer cylinder (3) and the external surface (6) of the inner cylinder (4), and suited to assume at least one rest configuration in which it is not dilated. The invention furthermore concerns a method for producing a thermostatically controlled cylinder and a system (100) for heat treating a product (PL), comprising at least one thermostatically controlled cylinder (1).

Description

THERMOSTATICALLY CONTROLLED CYLINDER FOR HEAT TREATMENTS, METHOD FOR MAKING SAID CYLINDER AND SYSTEM COMPRISING SAID CYLINDER.

TECHNICAL FIELD OF THE INVENTION

The present invention concerns the technical field of heat treatment systems for products, in particular of heat treatment systems for plate- like products.

In particular, the present invention concerns the technical field of the heat treatment systems for plate-like products that make use of one or more thermostatically controlled cylinders suited to interact with the plate-like product to be treated.

Even more particularly, the present invention concerns the production of a thermostatically controlled cylinder used in said heat treatment systems.

The invention furthermore concerns a system comprising said thermostatically controlled cylinder.

DESCRIPTION OF THE STATE OF THE ART

In various production sectors the use of heat treatment systems is known, which are used to make products intended for multiple applications.

During production, in one or more of the processing steps said products are typically subjected to a heat treatment, typically a surface treatment, intended to heat and/or cool them.

Thus, for example, in the textile industry, in the paper industry, in the industry of plastic materials or of leather processing etc., in a specific processing step the various materials in the form of a plate-like material (fabric, paper, tape, film, etc.) are subjected to a heat treatment, typically a heating process.

For this purpose, the material in the form of a plate-like material is conveyed onto the external surface of a revolving cylinder, known as thermostatically controlled cylinder. The external surface of the thermostatically controlled cylinder is heated up to the desired treatment temperature. In many applications, preferably, the plate-like material is conveyed between two opposite cylinders, wherein at least one of said cylinders is of the thermostatically controlled type. The thermostatically controlled cylinder is typically constituted by a metallic object in the shape of a cylinder, provided at its ends with pins suitable for the assembly of bearings that allow it to rotate and for connection to the power takeoff so that it can be driven by a motive power.

The thermostatically controlled cylinder is also provided with a conveyor system, typically arranged at the level of one or both of the rotation pins, which allows the inlet and outlet of a heating and/or cooling fluid that interacts with the external surface of the revolving cylinder in order to achieve its heating and/or cooling up/down to the desired temperature.

The fluids typically used for this purpose include: heated and/or refrigerated water, heated and/or cooled pressurized water, vapour, diathermic fluid (diathermic oil).

A first type of thermostatically controlled cylinder, known as drum, is characterized by a simple metallic cylinder partially filled with a fluid that can be directly heated internally by means of electric resistances, or heated or cooled externally using special structures called central units, and circulated inside the cylinder itself by means of suitable pumps. This type of cylinder is very economic but does not guarantee a uniform temperature on the external surface of the cylinder.

A variant of a thermostatically controlled cylinder of known type, called cylinder with a hollow space, comprises an outer metallic tube and an inner coaxial metallic tube. The space between the internal surface of the outer tube and the external surface of the inner tube constitutes a hollow space inside which the fluid that serves for the heating and/or cooling process circulates. The outer metallic tube will be the visible part of the cylinder with heated and/or cooled external surface.

In a first embodiment of said cylinders with hollow space, the hollow space is divided into a predetermined number of ducts, with the fluid flowing in from one side of the cylinder and flowing out of the opposite side.

A drawback associated with this embodiment is constituted by the fact that the operating temperatures on the side of the cylinder where the fluid inlet is located are always higher than on the opposite side.

This drawback has been solved in thermostatically controlled cylinders in which the fluid is forced to flow along predefined paths shaped in such a way that the fluid inlet and outlet are located on the same side of the cylinder; in this way a balanced temperature between the inlet and the outlet temperature of the fluid is obtained, thus achieving optimal results in terms of surface temperature precision.

According to a technology of known type for carrying out said fluid guide paths inside the hollow space, a compact structure is made by applying on the external surface of the inner tube, through a welding process, a plurality of shaped guide elements (or screws) that define the fluid paths and then applying the outer tube (or jacket), again through a welding process, to the shaped guide elements in order to define the hollow space with the respective paths. The final structure of the cylinder, therefore, appears as a welded and compact structure. The guide elements are typically constituted by pieces of weldable materials, such as heavy metals (for example, steel).

Also the thermostatically controlled cylinders with a hollow space made as described above, however, pose some drawbacks.

A first drawback posed by said cylinders derives from the fact that it is difficult to make the fluid guide paths inside the hollow space. In fact, as already mentioned, various steps are required for coupling and welding the metallic elements that make up the cylinder, in particular for coupling, by means of a welding operation, the guide elements with the inner tube and for coupling, by means of a welding operation, the outer tube with the guide elements, or alternatively for the hot assembly of the jacket on the inner tube provided with screws.

The result is, first of all, the high production cost of the metallic elements that require complex mechanical processing, with long production and assembly times.

Another drawback related to the compact structure of said cylinders is the impossibility or great difficulty found when it is necessary to intervene in order to perform routine and/or extraordinary maintenance operations such as the cleaning of the paths to remove blockages and/or encrustations.

Another drawback of said compact structures is the need to use predetermined metallic elements, both for the inner and outer tubes and for the metallic elements welded in the hollow space.

This leads to the need to select metallic elements with thicknesses exceeding pre- established minimum thicknesses, with consequent limitations related to the material and the overall weight of the cylinder.

The main object of the present invention is thus to at least partially resolve or limit the problems that characterize the solutions known in the art.

In particular, it is an object of the present invention to propose a solution that makes it possible to provide a thermostatically controlled cylinder with a hollow space that is simpler and/or quicker to produce compared to the thermostatically controlled cylinders with a hollow space of known type.

It is a further object of the present invention to propose a solution that makes it possible to provide a thermostatically controlled cylinder with a hollow space involving shorter production times and/or lower production costs compared to the cylinders of known type.

It is a further object of the present invention to propose a solution that makes it possible to provide a thermostatically controlled cylinder with a hollow space that can be easily inspected for maintenance operations and/or checks throughout the useful life of the cylinder itself.

It is another object of the present invention to propose a solution that makes it possible to provide a thermostatically controlled cylinder that allows more suitable materials to be chosen for its construction.

SUMMARY OF THE PRESENT INVENTION

The general concept on which the present invention is based is constituted by the idea of making a thermostatically controlled cylinder with a hollow space in which a thermal fluid flows along at least one path in order to heat and/or cool the outside of the cylinder itself, wherein said path is made with guide means constituted by an element arranged in said hollow space and suited to be dilated so that it assumes an operating configuration.

According to a first aspect of the present invention, therefore, the subject of the same is a thermostatically controlled cylinder for heat treating products, preferably plate-like products, said thermostatically controlled cylinder comprising an innner cylinder and an outer cylinder, wherein between the internal surface of said outer cylinder and the external surface of said inner cylinder a tightly sealed hollow space is defined that is suited to receive a thermal fluid intended to heat and/or cool said outer cylinder, said hollow space comprising guide means suited to convey said thermal fluid along at least one path; wherein said guide means comprise at least one dilatable element suited to assume at least one operating configuration, in which it is dilated and arranged in contact with said internal surface of said outer cylinder and said external surface of said inner cylinder, and suited to assume at least one rest configuration, in which it is not dilated.

In a preferred embodiment, the dilatable element contains an inflation fluid suited to be pressurized in order to bring the dilatable element to its operating configuration. Preferably, the dilatable element is made of a material suited to guarantee at least a radial dilation included between 15% and 20%.

In a preferred embodiment, the dilatable element comprises at least one end configured for the introduction of the inflation fluid.

According to a preferred embodiment, the dilatable element comprises at least one end suited to be sealed.

Preferably, the end suited to be sealed comprises a closing clamp.

Preferably, the end suited to be sealed comprises a control device suited to control the pressure of the inflation fluid.

In a preferred embodiment, the inflation fluid comprises oil.

In preferred embodiments of the invention, the guide means define a plurality of independent paths for said thermal fluid in the hollow space.

In a preferred embodiment, the thermostatically controlled cylinder of the invention comprises at least one first annular flange and at least one second annular flange that are spaced and arranged between the internal surface of the outer cylinder and the external surface of the inner cylinder in order to delimit the hollow space laterally and make it tight.

Preferably, the first annular flange and/or said at least one second annular flange comprises a plurality of holes suited to allow the passage of the dilatable element. Preferably, the inner cylinder comprises a plurality of holes suited to allow the passage of the dilatable element.

The size of said holes is conveniently smaller than the size of the dilatable element when it is dilated in its operating configuration.

Preferably, the thermostatically controlled cylinder of the invention comprises coupling and turning means at its ends.

Preferably, the thermostatically controlled cylinder of the invention comprises means for conveying the thermal fluid into and out of said hollow space.

The thermal fluid preferably comprises one among the following fluids: heated and/or refrigerated water, heated and/or cooled pressurized water, vapour, diathermic fluid, preferably diathermic oil.

The dilatable element preferably comprises a tubular element.

According to another aspect of the present invention, the subject of the same is a method for making a thermostatically controlled cylinder of the type described above, wherein said method comprises the following steps:

- preparing said inner cylinder; - applying said dilatable element in said rest condition in order to define, outside said inner cylinder, said at least one path for said thermal fluid;

- assembling said outer cylinder externally to said inner cylinder and to said dilatable element in order to obtain said hollow space;

^■ delimiting said hollow space laterally;

- arranging said dilatable element in said operating configuration.

Preferably, the step of arranging said dilatable element in said operating configuration comprises a step in which the dilatable element is dilated radially by pressurizing an inflation fluid that is inside the dilatable element.

Preferably, the step of delimiting the hollow space laterally comprises a step in which a first annular flange and a second annular flange are installed in such a way that they are spaced from each other and arranged between the internal surface of the outer cylinder and the external surface of the inner cylinder.

According to a further aspect of the present invention, the subject of the same is a system for heat treating products, said system comprising at least one :hermostatically controlled cylinder, wherein said thermostatically controlled cylinder is made as described above.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages, objects and characteristics as well as further embodiments of ;he present invention are defined in the claims and are clarified below by means 3f the following description, in which reference is made to the attached drawings; n the drawings, corresponding or equivalent characteristics and/or component jarts of the present invention are identified by the same reference numbers. In ^articular, in the figures:

^■ Figure 1 shows a system comprising a thermostatically controlled cylinder made according to a preferred embodiment of the invention;

■ Figure 2 shows an axonometric view of the thermostatically controlled cylinder of the system shown in Figure 1 made according to a preferred embodiment of the invention;

^■ Figure 3 shows the exploded axonometric view of Figure 2;

^■ Figure 4 shows an axonometric view of the thermostatically controlled cylinder of Figure 2 without some elements;

■ Figure 5 shows the axonometric view of Figure 4, where the elements that are not visible are drawn with a broken line;

^■ Figure 6 shows the assembly of Figure 4 without the outer cylinder; - Figure 7 shows an exploded view of some elements of Figure 6;

- Figure 8 shows the thermostatically controlled cylinder of Figure 2 without the outer cylinder;

- Figure 9 shows a sectional view of a portion of the cylinder of Figure 8 according to section line IX°-IX°;

- Figure 10 shows a schematic plan view of the assembly of Figure 8;

- Figure 1 1 shows an orthogonal sectional view, with respect to the longitudinal axis X, of the cylinder of Figure 2 in a first configuration (rest);

- Figure 1 1A shows an enlarged detail of Figure 1 1 ;

- Figure 12 shows the sectional view of Figure 1 1 in a second configuration (operating);

- Figure 12A shows an enlarged detail of Figure 12;

- Figure 13 shows a variant embodiment of Figure 10.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

Even though the present invention is described here below with reference to its embodiments illustrated in the drawings, the present invention is not limited to the embodiments described below and shown in the same drawings. On the contrary, the embodiments described and illustrated in the drawings clarify some aspects of the present invention, the scope of which is defined in the claims.

The present invention can be especially but not exclusively applied in the field of production of plate-like products, such as fabrics, paper, tapes, films etc., the production of which includes one or more processing steps requiring at least one surface heat treatment.

So, for example, in the textile industry, in the paper industry, in the production of plastic materials, in the leather processing industry etc. the various materials in the form of plate-like material (fabric, paper, tape, film etc.) are conveyed onto the external surface of a revolving cylinder, known as thermostatically controlled cylinder and constituting the subject of the present invention, and said external surface is brought to and preferably kept at a pre-determined temperature.

In some cases the external surface of the thermostatically controlled cylinder is heated and in other cases it can be cooled, depending on whether the required heat treatment is a heating or a cooling treatment, respectively. In particular applications, preferably, the plate-like material is conveyed between two cylinders arranged opposite each other, wherein at least one of said two cylinders is of the thermostatically controlled type and therefore constructed according to the present invention.

It should be noted, however, that the applications of the present invention are not limited to the case of plate-like products. On the contrary, the present invention can also be advantageously applied for all those products that need a heating and/or cooling treatment.

A thermostatically controlled cylinder 1 according to a preferred embodiment of the present invention is described here below with reference to Figures from 1 to 12.

Figure 1 schematically shows a system 100 comprising, among the other components, a thermostatically controlled cylinder 1 that is advantageously made according to the present invention. The figure also shows a plate-like product PL suited to be conveyed towards and placed in contact with the external surface 2 of the thermostatically controlled cylinder 1. For example, the system 100 can represent a coupling device suited to attach a plastic film (not illustrated) to a hide PL that is heated by means of the thermostatically controlled cylinder 1. Preferably, the system 100 comprises a second counteracting cylinder 101 (which normally is not thermostatically controlled).

The thermostatically controlled cylinder 1 according to the present invention comprises an outer cylinder 3 and an inner cylinder 4, preferably mounted coaxially.

The thermostatically controlled cylinder 1 is preferably developed around a longitudinal main axis X.

The external surface 2 of the outer cylinder 3 constitutes the thermostatically controlled surface suited to be placed in contact with the plate-like product PL to be treated. The expression "thermostatically controlled" indicates the characteristic thanks to which it is possible to adjust the temperature of an object, in the case at hand the outer cylinder 3, and if necessary maintain it at substantially constant values. The temperature to be reached can be higher than the normal temperature or ambient temperature of the object, in which case the object needs to be heated, or lower than the normal temperature or ambient temperature of the object, in which case the object needs to be cooled.

A hollow space 7, as can be seen in particular in Figures 11 A and 12A, is defined between the internal surface 5 of the outer cylinder 3 and the external surface 6 of the inner cylinder 4.

A thermal fluid FT suited to heat and/or cool the outer cylinder 3 and thus its external surface 2 is circulated inside the hollow space 7, as described below and according to the inventive concept introduced by the present invention. The outer cylinder 3 is preferably made of a material that allows a good heat transmission between the thermal fluid FT and the external surface 2, compatibly with the mechanical characteristics that the cylinder 3 must have in order to allow the heat treatment to be performed on the product to be treated. Preferably, the outer cylinder is made of steel, more preferably stainless steel. The external surface can also be preferably subjected to special treatments, such as polishing, satin finishing, sand-blasting, engraving etc., as well as coated with special anti- adherent materials or materials that are resistant to specific aggressive chemical agents.

The thermal fluids FT typically used may preferably comprise heated and/or refrigerated water, heated and/or cooled pressurized water, vapour, diathermic fluid (diathermic oil).

The thermostatically controlled cylinder 1 is provided at its first end 8 and at its second end 9 with corresponding coupling and turning means 10, 1 1. In particular, one of these coupling and turning means 10 comprises holding means suited to allow the thermostatically controlled cylinder 1 to be driven by a motive power that sets it turning.

The coupling and turning means 10, furthermore, are preferably associated with the conveying means 12 that are suited to convey the thermal fluid FT (both towards the hollow space 7 and from the hollow space 7).

In greater detail, in the embodiment described herein several paths are defined in the hollow space 7 for the thermal fluid FT, specifically four paths respectively indicated by PI, P2, P3 and P4 in the figures. The thermal fluid FT is conveyed towards the hollow space 7 through a main inlet way 13 of the conveying means 12 that is divided into four inlet ways 131, 132, 133, 134 for the corresponding paths P1÷P4 defined in the hollow space 7. The thermal fluid FT then flows out through four outlet ways 141, 142, 143, 144 that are joined in a single main outlet way 14 of the conveying means 12, after exchanging the thermal energy (heating or cooling) at least with the outer cylinder 3.

In the embodiment illustrated and described herein, in the hollow space 7 there are four paths P1÷P4 for the thermal fluid FT. Said paths P1÷P4, as well as the conveying means 12 that are better described below, are preferably distributed around the main axis X of the thermostatically controlled cylinder 1 in such a way that they are equally spaced from one another. This furthermore allows a good compromise to be achieved between construction complexity and efficiency of the heat exchange ensured by the thermal fluid FT. In fact, the more the paths defined for the thermal fluid inside the hollow space, the shorter each individual path. In this way, the difference between the temperature of the thermal fluid at the inlet and at the outlet of the respective path will be smaller, thus ensuring a more homogeneous heat exchange towards the outer cylinder.

In variant embodiments of the invention, however, the number and shape of the paths inside the hollow space can be different.

For example, there may be several paths, even not equally distributed, or even a single path. Furthermore, the shape of said paths inside the hollow space may comprise sections that are parallel to the main axis X and/or sections developed according to different patterns, for example helical patterns, as shown for example in Figure 13.

The hollow space 7 is limited at the level of said ends 8, 9 by respective annular closing flanges 18, 19 (better visible in Figure 6). The closing flanges 18, 19 are preferably connected to the external surface 5 of the inner cylinder 4 by means of a welding operation.

The paths P1÷P4 are defined inside the hollow space 7 by guide means 20. According to the present invention, the guide means 20 comprise at least one sealing element 21, or dilatable element, suited to assume an operating configuration shown in Figures 12 and 12 A.

More particularly, the sealing element 21 comprises a tubular element 21 and an inflation fluid FG, shown in detail only in Figure 12 A, is introduced therein and kept under pressure. The inflation fluid FG preferably comprises oil. In variant embodiments of the invention, the inflation fluid FG can be a different fluid, for example water, water with emulsified mixtures, air, air and gas mixtures etc. The tubular element 21 preferably comprises a deformable or radially dilatable pipe. The tubular element 21 is preferably made of silicone. The deformability of the tubular element 21 allows the same to assume said operating configuration, with the inflation fluid FG under pressure, and a rest configuration, with the inflation fluid FG not pressurized or even absent, as shown in Figures 1 1 and 1 1 A.

The deformability (radial dilatability) of the tubular element 21 is preferably included between 15% and 20%. The tubular element 21 has a preferably circular cross section. However, in variant embodiments said cross section can have any shape suited to allow said operating configuration to be achieved in any case.

The sealing element 21 of the embodiment illustrated and described herein preferably comprises a single tubular element 21 that is arranged according to a special zigzag configuration in order to define said paths P1÷P4 of the thermal fluid FT between the main inlet way 13 and the main outlet way 14.

The paths P1÷P4 of the thermal fluid FT are illustrated, in particular, in the plan view of the inner cylinder 4 shown in Figure 10.

In particular, in order to allow the tubular element 21 to be arranged in the zigzag configuration, the inner cylinder 4 comprises a first plurality of holes 25, visible in Figure 7, in proximity to the first flange 18 and a second plurality of holes 26 in proximity to the second flange 19. Furthermore, also the first flange 18 and the second flange 19 are provided with corresponding holes 27, 28.

Said holes 25, 26, 27, 28 have such a size as to allow the passage of the tubular element 21 in its rest configuration, while when the tubular element 21 is in its operating configuration, that is, dilated and under pressure, said holes 25, 26, 27, 28 are completely blocked and guarantee water tightness.

In the embodiment illustrated and described herein there is a single tubular element 21. This furthermore ensures reduced construction complexity. In variant embodiments, however, several independent tubular elements may be used, each one of which is independently deformable by means of the inflation fluid. Furthermore, the configuration of the one or more tubular elements inside the hollow space can be different in order to define the corresponding paths. For example, the one or more tubular elements can define, in the hollow space, paths for the thermal fluid with sections parallel to the main axis X and/or sections with different patterns, for example helical sections etc..

The steps for the construction of the thermostatically controlled cylinder 1 according to the invention are described here below. First of all, the inner cylinder 4 is prepared with its first and second plurality of holes 25, 26, and the first and the second flange 18, 19 are connected on the external surface 6 of the inner cylinder 4, preferably through a tight welding operation. The tubular element 21 in its rest configuration, meaning without inflation fluid FG inside it, is then mounted on the assembly constituted by the inner cylinder 4 and by the flanges 18, 19, as shown in Figure 6, making the tubular element 21 pass through the various holes 25, 26, 27, 28 so that it follows the desired path, meaning a zigzag path in the case at hand. A first end 21b of the tubular element is advantageously sealed, while the other end 21a is arranged so that in a successive step it can be connected to an external feeding system suited to deliver the inflation fluid FG. The outer cylinder 3, as shown in Figure 4, is mounted on the outside of the assembly obtained in this way and shown in Figure 6.

Successively, the coupling and turning means 10, 1 1 are assembled on the ends 8, 9 of the thermostatically controlled cylinder 1 , comprising the conveying means 12 that convey the thermal fluid FT.

Once said parts have been assembled, the inflation fluid FG is then introduced through the end 21a. The inflation fluid FG is then brought to the desired pressure in order to dilate the tubular element 21 and bring it to its operating configuration (the one shown in Figures 12 and 12 A) in order to create the paths P1÷P4 inside the hollow space 7. Once the pre-established pressure has been reached, the end 21a of the tubular element through which the inflation fluid FG has been introduced is sealed (for example, through a clamp). In a variant embodiment, a device suited to continuously control the internal pressure of the tubular element 21 is advantageously applied to the closing end 21a of the tubular element 21, for example a pressure gauge 125 (as schematically shown in Figure 10).

The conveying means 12 that convey the thermal fluid FT according to the preferred embodiment of the present invention are described, in particular, with reference to Figures 8 and 9.

As described above, the conveying means 12 are associated with the coupling and turning means 10 and allow the thermal fluid FT to be conveyed from the main inlet way 13 to the four inlet ways 131, 132, 133, 134 leading to the respective paths P1÷P4 provided inside the hollow space 7 and from the four outlet ways 141, 142, 143, 144 of the respective paths P1÷P4 to the only main outlet way 14 of the thermal fluid FT. Figure 8 shows, for the sake of simplicity, just one path PI out of the four provided, and also Figure 9 shows the cross section made at the level of the elements suited to feed said path PI .

The conveying means 12 comprise, in particular, an internal main duct 50 that defines said main inlet way 13. The main duct 50 ends into a first chamber 51, preferably cylindrical, provided with four holes 131a÷134a (only the first one visible in Figure 9), each one of which is connected to a corresponding delivery pipe 131, 132, 133, 134. The delivery pipes 131, 132, 133, 134 define said four inlet ways 131, 132, 133, 134 leading to the respective paths P1÷P4. For this purpose, the delivery pipes 131, 132, 133, 134 comprise corresponding terminal portions 131b÷134b (only the first one visible in Figure 9) that end into respective inlet holes 61a÷64a of the inner cylinder 4 (only 2 visible in the figures).

The conveying means 12 also comprise an external annular duct 70, preferably coaxial with the main duct 50, which defines said main outlet way 14 of the thermal fluid FT. The annular duct 70 comprises a second chamber 71 , preferably annular and cylindrical, provided with four holes 141a÷144a (only the first one visible in Figure 9), each one of which is connected to a corresponding return pipe 141, 142, 143, 144. The return pipes 141, 142, 143, 144 define said four outlet ways 141, 142, 143, 144 from the respective paths P1÷P4 provided for the thermal fluid FT. For this purpose, the return pipes 141, 142, 143, 144 comprise respective terminal portions 141b÷144b (only the first one visible in Figure 9) that are connected to corresponding outlet ways 61b÷64b of the inner cylinder 4 (only 2 visible in the figures).

So, for example, a possible path of the thermal fluid FT is the following: the thermal fluid FT flows in through the main inlet way 13 and is conveyed along the main duct 50 and into the first chamber 51 ; from the first chamber 51 it is conveyed, through the first delivery pipe 131, to the first inlet hole 61a in the inner cylinder 4; the thermal fluid FT follows the first path PI inside the hollow space 7 (during which the heat exchange with the outer cylinder 3 takes place) and flows out of the hollow space through the first outlet hole 61b and conveyed from the first return pipe 141 to the second chamber 71; finally, the thermal fluid FT flows out of the second chamber 71 through the annular duct 70 that constitutes the main outlet way 14 of the thermal fluid FT.

The thermostatically controlled cylinder 1 described above is ready to be applied to the system, for example the system 100 of Figure 1, which is ready to receive it. At the moment of use, the thermostatically controlled cylinder 1 is fed with the thermal fluid FT through the conveying means 12. During use of the thermostatically controlled cylinder 1 , the thermal fluid FT flows along the paths P1÷P4 inside the hollow space 7. While flowing along its path, the thermal fluid FT exchanges thermal energy with the outer cylinder 3, bringing the external surface 2 to the desired temperature. The thermostatically controlled cylinder 1 according to the present invention makes it possible to comfortably carry out the operations required for its disassembly, for example for routine and/or extraordinary maintenance (for example, cleaning of the internal surface 5 and/or of the outer cylinder 3 and of the external surface 6 of the inner cylinder 4 and/or of the external surfaces of the tubular element 21 that are the surfaces in contact with the thermal fluid FT and are thus subject to encrustations), or for the replacement of one or more components of the thermostatically controlled cylinder 1. In order to perform the disassembly operations, it will be sufficient to empty the thermal fluid FT from the hollow space, depressurize the tubular element 21, for example by releasing the closing clamp at the end 21a or removing the pressure gauge 125, and then the thermostatically controlled cylinder 1 can be opened (that is, the outer cylinder 3, the inner cylinder 4 and the tubular element 21 can be disassembled). It is thus possible to work comfortably and separately on the outer cylinder 3 and the inner cylinder 4 and on the tubular element 21. Once the various operations required have been performed on the different elements (for example cleaning and/or replacement), it will be possible to quickly reassemble the thermostatically controlled cylinder 1, through the operations already widely described above.

According to a first advantageous aspect, the thermostatically controlled cylinder 1 according to the present invention is simpler and quicker to construct than the systems of known type. In fact, this is due to the elimination of the complex and expensive mechanical processing and welding operations that involved inevitable stress relieving heat treatments and successive heating operations for fitting the outer cylinder on the inner cylinder, as the tightness of the circuits in the hollow space was the result of the close contact between the guides welded in the hollow space and the forced assembly of the outer cylinder.

Another advantageous aspect is constituted by the fact that, differently from the cylinders produced with the conventional methods, according to which the completed cylinder is a single body with a welded structure, the thermostatically controlled cylinder 1 according to the present invention can be completely disassembled using simple workshop tools and therefore at any moment of its life it can be rapidly opened (disassembled), inspected, cleaned and if necessary descaled and re-assembled, as already explained above.

According to another advantageous aspect, the thermostatically controlled cylinder 1 according to the present invention offers the possibility to make the outer cylinder 3 and the inner cylinder 4 separately and preferably in different materials.

In particular, the outer cylinder 3 is made with the material that is most suitable for processing the product PL to be treated and that at the same time allows the best thermal energy transmission between the thermal fluid FT and the external surface 2, for example stainless steel.

The inner cylinder 4, instead, can be made with a different material that can be selected so that the inner cylinder 4 is lighter than the outer cylinder 3, such as PVC. Furthermore, the material for the inner cylinder 4 can be selected in such a way as to obtain a high thermal resistance, so that the dispersion of thermal energy through the same is as limited as possible. In this way, the thermal energy dispersed towards the inside of the thermostatically controlled cylinder 1 is reduced to a minimum and most of this energy is transmitted to the outer cylinder 3.

According to another advantageous aspect, the thermostatically controlled cylinder 1 according to the present invention offers the possibility to make the guide means 20 so that they are lighter than the guide means of known type, typically in a weldable material such as steel, etc.

Preferably, in fact, the tubular element 21 that constitutes the guide means 20 is made of silicone and the inflation fluid FG is constituted by oil.

Figure 13 shows the plan view of the inner cylinder 4' of a variant embodiment of the thermostatically controlled cylinder of the invention.

This view shows a different configuration of the guide means 20' comprising a sealing element 2 , or tubular element, suited to define six paths, of which only one PI ' shown in the figure for the sake of simplicity.

In this embodiment, advantageously, the inner cylinder 4' is not holed and the tubular element 2 is positioned in the hollow space according to several paths, as shown in the figure. The changes of direction of the tubular element 2 , by way of example the corners A in the figure, are preferably obtained through suitable inserts (not shown) that are integral with the inner cylinder 4'.

Analogously, the terminal portions of the tubular element 2 , by way of example the terminal portions M in the figure, are preferably obtained through closing clamps (not shown) that seal the ends of the tubular element 21 ' and are integral with the inner cylinder 4'. The thermal fluid FT is conveyed from the main inlet way 13' towards the six paths provided inside the hollow space and then sent out through the main outlet way 14'.

The above clearly shows that the present invention allows the set objects to be achieved, in particular the object to provide a thermostatically controlled cylinder with a hollow space that is simpler and/or quicker to construct than the cylinders of known type.

While the present invention has been described with reference to the particular embodiments illustrated in the drawings, it should be noted that the present invention is not limited to the particular embodiments illustrated and described herein; on the contrary, further variants of the embodiments described fall within the scope of the present invention, which is defined in the claims.

Claims

1. Thermostatically controlled cylinder (1) for heat treating products (PL), preferably plate-like products (PL), said thermostatically controlled cylinder (1) comprising an inner cylinder (4) and an outer cylinder (3), wherein between the internal surface (5) of said outer cylinder (3) and the external surface (6) of said inner cylinder (4) a hollow space (7) is defined which is sealed and intended to receive a thermal fluid (FT) suited to heat and/or cool said outer cylinder (3), said hollow space (7) comprising guide means (20, 21; 21 ') for conveying said thermal fluid (FT) along at least one path (PI, P2, P3, P4; PI '), characterized in that said guide means (20, 21 ; 20', 2 Γ) comprise at least one dilatable element (21; 2Γ) suited to assume at least one operating configuration in which it is dilated and placed in contact with said internal surface (5) of said outer cylinder (3) and said external surface (6) of said inner cylinder (4) and suited to assume at least one rest configuration in which it is not dilated.

2. Thermostatically controlled cylinder (1) according to claim 1, characterized in that said dilatable element (21; 2Γ) comprises an inflation fluid (FG) suited to be pressurized in order to arrange said dilatable element (21; 21') in said operating configuration.

3. Thermostatically controlled cylinder (1) according to any of the preceding claims, characterized in that said dilatable element (21 ; 21 ') is made of a material that is suited to guarantee at least a radial dilation included between 15% and 20%.

4. Thermostatically controlled cylinder (1) according to claim 2 or 3, characterized in that said dilatable element (21; 21 ') comprises at least one end (21a) configured for the introduction of said inflation fluid (FG).

5. Thermostatically controlled cylinder (1) according to claim 4, characterized in that said dilatable element (21 ; 21 ') comprises at least one end (21b) suited to be sealed.

6. Thermostatically controlled cylinder (1) according to claim 5, characterized in that said end (21b) suited to be sealed comprises a clamp.

7. Thermostatically controlled cylinder (1) according to claim 5, characterized in that said end suited to be sealed comprises a device (125) for controlling the pressure of said inflation fluid (FG).

8. Thermostatically controlled cylinder (1) according to any of the preceding claims, characterized in that said guide means (20, 21; 2 ) define a plurality of independent paths (PI, P2, P3, P4; ΡΓ) for said thermal fluid (FT) in said hollow space (7).

9. Thermostatically controlled cylinder (1) according to any of the preceding claims, characterized in that it comprises at least one first annular flange (18) and at least one second annular flange (19) spaced from each other and arranged between said internal surface (5) of said outer cylinder (3) and said external surface (6) of said inner cylinder (4) in order to laterally delimit and seal said hollow space (7).

10. Thermostatically controlled cylinder (1) according to claim 9, characterized in that said first annular flange (18) and/or said at least one second annular flange (19) comprise a plurality of holes (27, 28) intended to allow the passage of said dilatable element (21 ; 2 Γ).

1 1. Thermostatically controlled cylinder (1) according to any of the preceding claims, characterized in that said innner cylinder (4) comprises a plurality of holes (25, 26) intended to allow the passage of said dilatable element (21).

12. Thermostatically controlled cylinder (1) according to any of the preceding claims, characterized in that said dilatable element (21 ; 2 ) comprises a tubular element (21 ; 21 ').

13. Method for producing a thermostatically controlled cylinder (1) according to any of the preceding claims, characterized in that it comprises the following steps:

- preparing said inner cylinder (4);

- applying said dilatable element (21 ; 21 ') in said rest configuration so as to define, outside said inner cylinder (4), said at least one path (PI, P2, P3, P4; PI ') for said thermal fluid (FT);

- assembling said outer cylinder (3) outside said inner cylinder (4) and said dilatable element (21; 2 Γ) so as to obtain said hollow space (7);

- delimiting said hollow space (7) laterally;

- arranging said dilatable element (21; 21 ') in said operating configuration.

14. Method according to claim 13, characterized in that said step of arranging said dilatable element (21; 2 Γ) in said operating configuration comprises the step of radially dilating said dilatable element (21 ; 2 ) by pressurizing an inflation fluid (FG) contained in said dilatable element (21 ; 2Γ).

15. Method according to claim 13 or 14, characterized in that said step of delimiting said hollow space (7) laterally comprises the step of applying a first annular flange (18) and a second annular flange (19) spaced from each other and arranged between said internal surface (5) of said outer cylinder (3) and said external surface (6) of said inner cylinder (4).

16. System (100) for heat treating a product (PL), said system (100) comprising at least one thermostatically controlled cylinder (1), characterized in that said thermostatically controlled cylinder (1) is a thermostatically controlled cylinder (1) according to any of the claims from 1 to 15.