EA001710B1 - Radiator, in particular for heating system, with a high resistance to internal pressure - Google Patents

Abstract

1. A radiator comprising at least one module, in turn comprising a tubular portion with a flat cross section; opposite top and bottom ends having respective lateral hydraulic fittings substantially aligned along a minor axis of the cross section; and a finned portion formed integrally in one piece with a lateral wall of the tubular portion; the finned portion including first fins originating directly from the tubular portion, and second fins originating transversely from respective front ribs in turn originating from the tubular portion and perpendicular to the first fins; the ribs being substantially aligned with a major axis of the cross section; characterized in that the cross section has a dimension (D), measured along the major axis, smaller than or equal to approximately 45% of the depth (P) of the module, also measured along the major axis. 2. A radiator as claimed in Claim 1, characterized in that a root portion of each rib has no fins, and comprises a number of respective ridges connecting the rib both to the lateral wall of the tubular portion, and to a respective second fin carried by the rib and immediately adjacent to the tubular portion. 3. A radiator as claimed in claim 1 or 2, characterized in that said cross section of the tubular portion has a wall thickness (S) ranging between approximately 2.4 and approximately 4.5 mm. 4. A radiator as claimed in one of the foregoing Claims, characterized in that said cross section of the tubular portion has a dimension (L), measured along the minor axis, equal to or greater than approximately 15% of the dimension (D) of the same cross section measured along the major axis. 5. A radiator as claimed in any one of the foregoing Claims, characterized in that the dimensions (D) (L) measured along the major axis (X) and minor axis (Y) of each cross section (4) may vary along the axial extension of the tubular portion (3), or may remain substantially constant along the whole axial extension of the tubular portion (3). 6. A radiator as claimed in any one of the foregoing Claims, characterized in that, at least along an axial portion of the tubular portion having said first fins, said cross section of the tubular portion is in the shape of a substantially rectangular ring with rounded corners and slightly outward-curving sides. 7. A radiator as claimed in any one of the foregoing Claims, characterized in that the depth (P) of the module, measured along the major axis of the cross section of the tubular portion, is over 80 mm.

Description

The present invention relates to a radiator, in particular, to a light alloy radiator suitable for installation in residential and industrial heating systems, and is characterized by a geometric characteristic that imparts high resistance to internal pressure.

As you know, modern radiators for heating systems can contain a number of standard sections, hermetically assembled side by side in a block and connected to the pipeline network of the system. The sections can be made of light alloy and contain a tubular part through which the heat transfer medium flows and a ribbed part which is integral with the tubular part and which receives heat transferred by the heat exchange medium and exchanges this heat with the environment by convection or radiation .

In order to be able to compactly connect the sections side by side, the tubular part usually has a flat cross section, as shown, for example, in FIG. 1, which is usually constant over the entire length (height) of the tubular part and essentially has the shape of a rhombus, a rectangle or a double isosceles trapezoid with rounded edges and maximum transverse dimensions, measured in parallel to two perpendicular axes of symmetry, denoted by X (major axis, i.e. parallel to the large size) and Y (small axis). Two protrusions extend from the end edges of the rhombus at the opposite ends of the major axis X, from which a number of transverse ribs depart; in addition, the ribs extend directly from the side wall of the tubular part and, in particular, from the same end edges from which the protrusions extend.

Radiators containing known sections of the above type have a low resistance to internal pressure. In particular, in a tensile test, known radiators are destroyed by the internal pressure of the heat transfer medium equal to 1.4-2.4 MPa, while radiators capable of withstanding higher pressures usually have a tubular part with a thicker side wall, which leads to an increase in both weight and cost.

The objective of the present invention is to provide an inexpensive, lightweight radiator for residential heating systems of public buildings, which can be made of light alloy (or similar material) and which provides both effective heat transfer and tensile resistance, which is much higher than the tensile resistance of known radiators, for example , over 3.0 MPa.

According to the present invention, there is provided a radiator comprising at least one section, in turn comprising a tubular part with a flat cross section; opposite upper and lower ends having corresponding lateral hydraulic connections located essentially coaxial to the minor axis of the cross section; and a ribbed portion integrally formed with the side wall of the tubular portion and comprising first ribs extending directly from the tubular portion and second ribs laterally extending from the corresponding front protrusions, in turn extending from the tubular portion and perpendicular to the first ribs, wherein the protrusions are located essentially on a straight line with a major axis of the cross section, characterized in that the cross section has a dimension measured along the major axis less than or equal to approximately 45% of the width of the section, also emoy along the major axis.

In addition, the base of each protrusion is made without ribs and contains a series of corresponding combs connecting the protrusion with both the side wall of the tubular part and the corresponding second rib made on the protrusion and directly adjacent to the tubular part.

The geometry determined by the above parameters provides radiators capable of resisting internal pressures above 3.5-4.0 MPa, while continuing to have a relatively thin wall of the tubular part (2.4-4.5 mm) and, therefore, light weight and low cost while maintaining the overall dimensions of the section, completely compatible with the currently used heating systems (section depth - over 80 mm; any section height, measured along the axis of the tubular part; very dense assembly in the block side by side to the limit nnyh spaces).

These favorable, unexpected distinguishing features experimentally determined are due to the favorable stress distribution achieved due to the geometric characteristic according to the present invention, which, determined by an appropriate combination of dimensional parameters and shape parameters, allows better distribution of stresses caused by internal pressure in the tubular part, while at the same time giving the ability of the ribs to actively contribute to the absorption of at least part of the stresses and, consequently Therefore, improving the mechanical strength of the tubular part.

A non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which FIG. 1 shows a cross section of a known section of a radiator (with a diamond-shaped water chamber);

FIG. 2 shows, not to scale, various cross-sections at different heights of the heatsink sections according to the present invention;

FIG. 3 shows, on a smaller scale, three views of the radiator section of FIG. 2, namely, a view in longitudinal section (Fig. 3a), a rear view (Fig. 3b) and a side view (Fig. 3c).

In FIG. 2 and 3, 1 denotes a radiator for housing and industrial heating systems, from which only one section 2 is shown for simplicity. As you know, a radiator can contain any number of sections 2, tightly connected side by side to a block.

For this purpose, each section 2 contains a tubular part 3 having a substantially vertical longitudinal axis and a flat radial cross section 4, and a ribbed part 5 integrally formed with the side wall 6 of the tubular part 3. Section 4 is a plane with very different transverse dimensions measured parallel to two perpendicular axes of symmetry, designated as X and Y. More specifically, since the size along the X axis is larger than the size along the Y axis, hereinafter the X axis is called the major axis, and the Y axis is called the minor axis.

The opposite upper and lower ends 7, 8 of the tubular part 3 on the sides are provided with corresponding cylindrical hydraulic connections 10 located essentially coaxial to the minor axis Y of the corresponding cross section 4, i.e., with the corresponding axes of symmetry, essentially coaxial to the axis Y of section 4 located on that the same height as the axis of the joints 10, i.e. in the same longitudinal position (relative to the axis of symmetry of part 3) as the connection 10.

Each section 2 is preferably made of a light alloy or similar material by injection molding, in which the lower end 8 is open and, when used, is closed in a known manner using a welded plug 8a.

The ribbed portion 5 comprises a first group of ribs 11 extending directly from the tubular portion 3, and a second group of ribs 12 transversely extending from the corresponding front protrusions 13, which, in turn, extend from the tubular portion 3 and perpendicular to the ribs 11. The protrusions 13 essentially are on the same line with the major axis X of the entire cross section 4 of the tubular part 3.

According to a first distinguishing feature of the invention, each cross section 4 of the tubular part 3 has an internal dimension B, measured along the major X axis, less than or equal to approximately 45% of the depth P of section 2, also measured parallel to the X axis of the corresponding section 4 (FIG. 2). Thus, for each section 4, the following inequality

I) <0.45 P (1)

Equation (1) is applicable, in particular, to the cross section 4 in the plane CC (Fig. 2), i.e. to section 4 corresponding to the lower end (i.e., closest to the joints 10 at the end 8) of the fin part 15 of the tubular part 3 defined by the longitudinal part of the part 3 provided with ribs 11.

Equation (1) is also applicable to the rest of the length of the finned part 15, except that due to the manufacture of sections 2 by injection molding, the value B, as is known to any specialist in injection molding, should be further reduced by the value due to the taper.

Depending on the overall dimensions of section 2 (full length, i.e. the height of the tubular part 3, which can be any length, and a width P, which must be more than 80 mm), the thickness 8 of the side wall 6 of the tubular part 3 is ideally in the range between approximately 2.4 and 4.5 mm. These values refer to the average thickness 8, calculated as the arithmetic average of two values of the wall thickness 6, measured at diametrically opposite points of the corresponding section 4.

According to a preferred feature of the invention, each cross section 4 of the tubular portion 3 has a dimension L, measured along the minor axis Υ, which is equal to or greater than about 15% of dimension B of the same cross section 4, measured along the major axis X. Therefore, the following equation applies:

B> 0.15 B (2)

Equation (2) is applicable, in particular, to the cross section 4 in the plane CC (Fig. 2).

According to a third distinguishing feature of the invention, each protrusion 13 has a base 20 without ribs 12, which departs from a corresponding side wall 6 of the tubular part 3 not having ribs 11; the base 20 of each front protrusion 13 contains a series of corresponding scallops 22 along the entire length of the finned part 15; combs 22 are made in such a way as to connect each protrusion 13 with both a part of the side wall 6 of the tubular part 3, from which the base 20 departs, and with a rib 12 closest to the base 20, i.e. with a rib on the protrusion 13, directly adjacent to the tubular part 3.

Finally, as clearly shown in FIG. 2, dimensions B and b of each cross section 4, measured along the major and minor axes X and Υ, may vary along the axial extent of the tubular part 3 or may remain substantially constant throughout the axial extent of the tubular part 3, provided that, as is obvious, equations (1) and (2) will be satisfied.

At least throughout the finned part 15, the cross-section 4 of the tubular part 3 can thus have the shape shown in planes AA and BB in FIG. 2, i.e. a substantially rectangular ring with rounded corners and slightly outwardly curved sides. Conversely, in the CC plane, it can be similar to the shape of a rhombus, but with different size ratios along the major and minor axes X and Υ in accordance with equations (1) and (2).

The invention will now be further described by way of test.

Example

To determine the actual difference in efficiency between the described radiator and a conventional radiator, hydraulic tests were carried out for breaking of six two-section units, i.e., six different radiators, each of which contained two sections located side by side.

All three known radiators, two of which were manufactured by the applicant and one purchased, had the cross section shown in FIG. 1, the depth P is more than 80 mm, and the inner dimension Ό along the major axis of the water chamber (the channel through which the heat exchange medium flows) was equal to or greater than 0.50 P (50% of P) (in particular, in cross section 4 in the plane CC in Fig. 2).

The above three radiators and three radiators according to the present invention were tested one after another, connecting them in series with a test circuit equipped with a variable displacement pump. After the connection, the water pressure inside each radiator was gradually increased from 0.3 MPa, increasing the pressure by 0.1 MPa per minute until the radiator ruptured. Pressure values were continuously recorded using a manometer with a recording device. The results are shown in the table.

Table

State of the art Invention Radiator one 2 3 4 5 6 Bursting pressure 1.4 MPa 1.5 MPa 2.1 MPa 3,5 MPa 4.0 MPa 3.8 MPa

CLAIM

Claims (7)

CLAIM 1. A radiator containing at least one section, in turn having a tubular part with a flat cross section; opposite upper and lower ends having corresponding lateral hydroconnections located essentially coaxially with the minor axis of the cross section; and a ribbed part made in one piece with the side wall of the tubular part and having first ribs extending directly from the tubular part, and second ribs transversely extending from the corresponding front projections, in turn, extending from the tubular part and perpendicular to the first ribs, with this protrusions are located essentially on the same straight line with the major axis of the cross section, characterized in that the cross section has a size (Ό), measured along the major axis, less than or equal to about 45% of the width (P) of the section, also from eryaemoy along the major axis. 2. The radiator according to claim 1, characterized in that the base of each protrusion is made without ribs and has a number of corresponding scallops connecting the protrusion both with the side wall of the tubular part and with the corresponding second edge made on the protrusion and immediately adjacent to the tubular part. 3. The radiator under item 1 or 2, characterized in that the cross section of the tubular part has a wall thickness (8) in the range between approximately 2.4 and approximately 4.5 mm. 4. A radiator according to any one of the preceding claims, characterized in that the cross section of the tubular part has a size (b), measured along the minor axis, equal to or greater than approximately 15% of the size (Ό) of the same cross section, measured along the major axis. 5. A radiator according to any one of the preceding claims, characterized in that the dimensions (Ό) and (b), measured along the major axis (X) and the minor axis (Υ) of each cross section (4), are adapted to vary along the axial length of the tubular part (3) or with the ability to remain essentially constant along the entire axial extent of the tubular part (3). 6. A radiator according to any one of the preceding claims, characterized in that, at least along the axial portion of the tubular portion having first ribs, the cross section of the tubular portion is an area bounded by closed curves in the form of substantially rectangles with rounded corners and slightly curved out by the sides. 7. A radiator according to any one of the preceding claims, characterized in that the width (P) of the section, measured along the major axis of the cross section of the tubular part, is more than 80 mm.