WO2008107743A1

WO2008107743A1 - Method for clamping a conduit for heat exchanger

Info

Publication number: WO2008107743A1
Application number: PCT/IB2007/052431
Authority: WO
Inventors: Federico Guastaroba
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-03-02
Filing date: 2007-06-22
Publication date: 2008-09-12
Anticipated expiration: 2009-09-02
Also published as: ITBS20070013U1

Abstract

Method for clamping a conduit (2) to a solid body (1) for the purpose of obtaining a heat exchange between the conduit (2) and the solid body (D-, including the steps of : - arranging a seat (3) on a surface of the solid body (1); - positioning the conduit (2) within the seat (3); and - exerting a force sufficient to modify the morphological characteristics of the conduit and/or the seat, so as to mechanically clamp the conduit to the solid body by mechanical deformation of the shape of the section of the conduit and/or, respectively, the section 'of the seat. The heat exchanger carried out with the method can show a width of the mouth of the seat smaller than the maximum width of the conduit.

Description

METHOD FOR CLAMPING A CONDUIT FOR HEAT EXCHANGER

The subject of the present invention is a method for carrying out heat exchangers through a clamping obtained by mechanical deformation of an hydraulic or pneumatic circuit in a pre-arranged seat in a given solid body. In detail, the invention describes a novel method for the application of a hydraulic or pneumatic circuit (obtained by circulating a liquid or gaseous substance within one or more pipes) to a solid body for the purpose of transmitting and/or receiving from the same a thermal influence by contact. It is known, in fact, that the physical contact amongst materials with different temperatures generates in both a mutual influence on the respective temperature. For the purpose of obtaining a physical contact between a moving liquid or gaseous material and a solid body, it is necessary to restrain the liquid or gaseous material within a forced conduit. Said forced conduit takes or gives thermal energy from the liquid and/or gaseous element, which passes through it, and in turn it takes and/or gives thermal energy from the surrounding in which it is contained; therefore, by maintaining in a physical contact the forced conduit with a solid body, said conduit becomes the means of the heat exchange between the liquid or gaseous material contained therein and the solid body contacting therewith.

In general, the process of the art known for stably associating a forced conduit to a solid body consist of welding/brazing, bonding (for example with thermic cement) methods, or mounting/fixing through the use of screws or rivets. The method subject of this patent is aimed to obtain an optimization in technical/economical terms of the fixing of said forced conduit to a given solid body, by obtaining a simplification of the assembly process. In one aspect, the present invention relates to a method for clamping a forced conduit to a solid body for the purpose of obtaining a heat exchange between a solid element and a liquid or gaseous substance. Said irreversible fixing step includes a mechanical deformation process of the used materials. In another aspect, the process includes the step of constituting on a solid body an anchorage seat for the positioning and the clamping by mechanical deformation of a forced conduit.

In another aspect, the method includes the step of positioning a forced conduit in a pre-arranged seat on a surface of a solid body. In a further aspect, the method of the present invention includes the step of exerting a sufficient force to modify the morphological features of the used elements, so as to obtain amongst the same a mechanical clamping sufficient for maintaining into contact the surfaces of said elements, causing a mutual thermal influence. In a still further aspect, the method is characterized in that, following to one or more mechanical actions, the forced conduit remains restrained within the housing seat so as to be into contact with the solid. In a still further aspect of the invention, the result obtained by the method is that the section of the forced conduit (B in Fig. 1) has greater dimensions than those of the housing seat (A in Fig. 1). In still another aspect, the method is characterized in that the object of mechanical deformation is the shape of the section of the forced conduit (fig. 3A and 3B).

In still another aspect, the method is characterized in that the object of the mechanical deformation is the shape of the section of the housing seat of the forced conduit (fig. 4A and 4B). In particular, the object of the mechanical deformation are the longitudinal edges of the seat. The section of the seat subjected to mechanical deformation is merely defined by said solid body, in particular said edges are an integral part of the solid body.

In still another aspect, the method is characterized in that the object of the mechanical deformation is both the shape of the section of the housing seat of the forced conduit, and the shape of the section of the forced conduit (fig. 5A and 5B). Further features and advantages of the present invention will become more apparent from the indicative and therefore not restrictive description of some preferred but not exclusive embodiments of a heat exchanger, as it is shown in the enclosed drawings, in which:

- figure 1 shows, in a cross-section of the seat and the conduit, a preferred embodiment of the heat exchanger according to the present invention;

- figure 2 shows, in a cross-section, the seat according to an example of the present invention; - figures 3A and 3B shown, in a cross section, two subsequent steps of an embodiment example of the method according to the present invention;

- figures 4A and 4B show, in a cross-section, two subsequent steps of a further embodiment example of the method according to the present invention;

- figures 5A and 5B show, in a cross section, two subsequent steps of a still further embodiment example of the method according to the present invention;

- figure 6 shows, in a cross section, a step of a still further embodiment example of the method according to the present invention;

- figure 7 shows, in a cross section, a step of a still further embodiment example of the method according to the present invention; - figures 8 and 9 show, in a cross section, two embodiment variations of the seat according to the present invention;

- figure 10 shows, in a cross section, a step of a still further embodiment example of the method according to the present invention. Figure 1 represents, in summary but not binding terms, the result obtained through the application of the present invention. From said image it is pointed out how the seat 3 existing on the solid body 1 and in which the forced conduit 2 has been inserted, following to a mechanical deformation, shows a smaller section A with respect to the section of the conduit B itself, giving rise, from one side, to an irreversible clamp- ing and from the other side obtaining a direct contact, in terms of heat interchange, between the conduit and the solid body containing the same. As shown in figure 1 , the section A is the width (shown by a two- pointed arrow in figure 1) of the inlet mouth of the seat 3, taken on the cross section. It has to be noted that the seat has a longitudinal development (normal to the plane of the figure), being suitable for receiving the conduit which notoriously has a longitudinal development. As shown in figure 1 , the section B is the maxi- mum width on the cross section (shown by a second two-pointed arrow in figure 1) of the conduit. Due to the physical contact between the internal wall of the seat and the external wall of the conduit, according to the present invention, such section B corresponds with the maximum cross width of the seat. The present invention consists of a method for keeping into contact the forced conduit and one or more solids for the purpose of obtaining and therefore carrying out a heat exchange between them. Said invention presents a further purpose, namely to fix the circuit of the forced conduit within the seat in which it has been inserted by restraining the same within a housing which maintains it in a determined position. With reference to figures 3A₁B. 4A,B and 5A,B for obtaining said fixing, it is necessary to make on the solid body, for example with a rounded or elliptical-pointed cutter, a housing which allows the positioning of a forced conduit therein. Said housing will need a shaping suitable for allowing the clamping of the conduit following to an occurred deformation.

During or following to the positioning of the forced conduit within the shaped section on the solid body, a pressure action will have to be exerted, which cause a proper mechanical deformation until the obtainment of the clamping/fixing of the forced conduit in said direction, giving rise to the heat interchange between the conduit itself and the body containing the same. Said deformation, resulted from a pressing or rolling action, could interest the forced conduit and the housing seat, or both.

It is believed opportune to specify that the mechanical deformation, foreseen as above shown for the fixing of the conduit to the solid body, can involve both the conduit itself (fig. 3A and 3B) and the housing seat (fig. 4A-4B) or both (fig. 5A-5B). When the deformation involves the conduit, it must necessarily be consti- tuted by a mechanically anelastic material, such that the mechanical deformation imparted thereto permanently remains, as shown in the figures 3B and 5B. When the deformation involves the portion of the solid body defining the edges of the seat (figures 4A₁B and 5A₁B), such portion, and preferably the entire solid body, must necessarily be constituted by a mechanically anelastic material, such that the mechanical de- -A - formation imparted thereto permanently remains, as shown in the figures 4B and 5B. When the deformation only involves the section of the seat (figures 4A₁B), it not necessary that the conduit is made of a mechanically deformable material in a substantially anelastic way, therefore it can also be made of a plastic and/or rubbery material. At the end of said method, the clamping of the forced conduit within a seat carried out on the surface of a solid will be obtained, giving rise, through the contact between the internal surfaces of the same seat, to the thermal transmission between said elements.

Figures 2, 6, 7, 8, 9 and 10 represent some possible non binding examples of sections of housing seats for positioning the forced conduit and clamping the same therein. Fig. 2 represents an elliptical section for clamping a forced conduit, said clamping is obtained by directly acting on the conduit itself through a pressure action. For example, as shown in Figure 3A, 4A and 5A, the dimension of the conduit along the direction of the seat depth (namely the cross dimension perpendicular to the solid surface) is greater than the depth of the seat itself. For example, with reference to figures 2 and 3A, the width A of the mouth of the seat is equal to about 8 mm, the diameter of the circular section of the conduit is equal (subject to a slight tolerance for allowing the insertion) to the width A of the mouth, the maximum width B of the chamber of the seat is equal to about 9 mm and the depth of the seat is equal to about 5.5 mm. Once the conduit has been inserted in the seat, a pressure on the portion of the conduit remaining protruding (in the above example up to a projection of about 2.5 mm) is exerted relative to the surface of the solid body. In this way, such portion is pressed inwardly of the seat, while the portion of conduit which is already within the seat tends to transversally expand. Such pressing action can be carried out until the complete flattening of the portion of the conduit which was previously protruding on the surface of the solid body, as shown in figure 2B, or alternatively, as shown in figure 1 , at the end of the deformation process of the conduit, a part of the conduit can remain slightly protruding from the surface of the solid body. Fig. 6 represents a circular-shaped section, wherein the clamping is obtained through a pressure action di- rectly applied on the conduit, which will have an elliptical shape, as shown by way of example in figure 6. Alternatively (not shown in figure), the conduit could have a circular section, with, for example, the width A of the mouth of the seat equal to 8 mm, the diameter of the circular section of the conduit equal to the width A of the mouth, the maximum width B of the chamber of the seat equal to 8.5 mm and the depth of the seat equal to 6.5 mm. Fig. 7 represents a seat with a substantially rectangular (as shown in figure) or squared section with bulged side walls, thought for the clamping through a pressure directly applied on the conduit, which in this case will have a substantially squared or rectangular-shaped section (as shown in figure). Fig. 8 shows an alternative housing section to those shown in figure 4A and 5A for the clamping of a forced conduit obtained through the mechanical deformation of two opposite lips existing on the two longitudinal edges of the mouth of the seat.

Fig. 9 represents an asymmetric section for the clamping of a forced conduit obtained through the mechanical deformation of a single lip existing on the mouth of the seat. Fig. 10 represents a section of the seat in which the width of the mouth is substantially equal to the maximum width of the seat. In other words, the seat shows at its entrance a well with parallel walls with knurled sides 10. The conduit can have a circular or preferably, as shown in figure 10, elliptical section. The clamping is obtained directly acting on the conduit itself by applying a pressure. In this case, it is important that following to the aforesaid pressure action, the conduit comes into a forced contact with the knurled sides 10, so as to remain clamped by friction on said knurlings. For allowing this, the conduit must have such shape and dimensions that, once inserted in the seat and before the pressure, it contemporaneously hits the bottom of the seat and protrudes from the surface of the solid body. In other words, the dimension along the depth direction of the seat must be greater of the depth itself of the seat. Following to the pressure action, the conduit is bulged within the seat so as to define a forced contact on the two opposite and knurled walls 10 of the seat 3. By forced contact one means that, after the mechanical deformation of the conduit is occurred, the conduit itself exerts a pressure on the two side and opposite walls of the seat.

Optionally, knurlings can be arranged along all the depth of the side walls. Optionally, knurlings can be applied to all the embodiment examples described in this application; for the puφose of rendering stronger the anchorage of the conduit to the seat. Concerning this, it is to be noted that in the different embodiments of the present invention, the anchorage between the conduit and the seat is obtained thanks to at least one between two factors, one factor bound to the geometrical forms of the seat and the conduit, as shown in figure 1 , 3B, 4B and 5B, and one factor bound to the pressure that the deformed conduit exerts on the internal walls of the seat, particularly on the two side and opposite walls. This second factor can synergically co-operate with the knurlings above described. Preferably, the anchorage is obtained thanks to both factors.

By way of example, the conduit can be made of copper. The solid body can be made, for example, of iron or preferably aluminium or an aluminium alloy. In one alternative, not shown in the figures, the dimension of the conduit along the depth direction of the seat can also be lower than the depth of the seat itself. Advantageously, in this case, the conformation of the seat presents at the entrance a well with parallel walls until a determined depth, to which a chamber is extended, for example with an elliptical, circular or substantially rectangular section, having a maximum width greater than the entrance width. Once the conduit has been inserted within the chamber, it is com- pletely inside the seat, without projections from the surface of the solid body. Also in this case, it is possible to exert a mechanical action on the conduit portion accessible from the mouth of the seat. In this way, such portion is pressed towards the bottom of the seat, while the side walls of the conduit tend to transversally enlarge taking possession of the chamber.

In an embodiment, the conduit can be an electrical resistance suitable for being crossed by electric current and thus producing heating by Joule effect. For the inventive embodiments in which the conduit is deformed, it is necessary that such resistance is anelastically deformable, for example thanks to a hollow ring-section, such as those shown in the figures.

Claims

1. Method for clamping a conduit to a solid body for the purpose of obtaining a heat exchange between the conduit and the solid body, including the steps of:

- arranging a seat on a surface of the solid body; - positioning said conduit in said seat;

- exerting a force sufficient to modify the morphological characteristics of the conduit and/or the seat, so as to mechanically clamp said conduit to said solid body by mechanical deformation of the shape of the conduit section and/or, respectively, the section of the seat.

2. Method according to claim 1 , wherein such mechanical deformation is anelastic.

3. Method according to claim 1 or 2, wherein such clamping is irreversible.

4. Method according to claim 1 or 2 or 3, wherein, after the step of exerting a force, the width (A) of the mouth of the seat is smaller than the maximum width (B) of the conduit.

5. Method according to any one of the preceding claims, wherein said seat has an elliptical section.

6. Method according to any one of the claims 1 to 4, wherein said seat has a circular section.

7. Method according to any one of the preceding claims, wherein said mechanical clamping is obtained by directly acting on said conduit through a pressure action, so as to impart said anelastic mechanical deformation to said conduit.

8. Method according to any one of the preceding claims, wherein said mechanical deformation is obtained with a rolling or pressing action.

9. Method according to any one of the preceding claims, wherein said conduit is a pipe.

10. Method according to any one of the preceding claims, wherein after the step of positioning the conduit and before the step of exerting a force, the dimension of the conduit along the direction of the seat depth is greater than the depth of the seat itself.

11. Method according to any one of the preceding claims, wherein, before the step of exerting a force, the width (A) of the mouth of the seat is smaller of the maximum width (B) of the seat.

12. Method according to any one of the preceding claims, wherein, after the step of exerting a force, substantially all the internal surface of said seat is into contact with the corresponding external surface of said conduit.

13. Heat exchanger (5) including: - a solid body (1);

- a seat (3) obtained on a surface of the solid body; and

- a conduit (2) inserted in said seat through anelastic mechanical deformation of said seat and/or said conduit, such that substantially all the internal surface of said seat is into contact with the corresponding exter- nal surface of said conduit.

14. Heat exchanger according to claim 13, wherein the width (A) of the mouth of said seat is smaller than the maximum width (B) of the conduit.

15. Heat exchanger according to claim 13 or 14, wherein said conduit is a forced conduit.

16. Heat exchanger according to claim 13 or 14 or 15, further including a hydraulic or pneumatic circuit including said conduit.

17. Heat exchanger according to any one of the claims 13 to 16, wherein said conduit is such that the shape of its cross section is mechanically deformable in an anelastic way.

18. Heat exchanger according to any one of the claims 13 to 17, wherein said seat is such that the shape of its cross section, such as only defined by the solid body, is mechanically deformable in an anelastic way.

19. Heat exchanger according to any one of the claims 13 to 18, wherein said seat has a circular or elliptical shaped-section.

20. Heat exchanger according to any one of the claims 13 to 19, wherein said seat has two side and opposite walls and said conduit exerts a pressure on said walls.

21. Radiating element including the heat exchanger according to any one of the claims 13 to 20.